Green and Golden Bell Frogs - Gosford City Council

Biosphere Environmental Consultants Pty Ltd

___________________________________________________Plan of Management 

North Avoca and Davistown Green and Golden Bell Frogs 

Plan of Management 

for the Green and Golden Bell Frog 

at North Avoca and Davistown. 

List of Contents 

1.0 Executive Summary 

2.0 Introduction 

2.1 Purpose of the Plan 

2.2 History of the Green and Golden Bell Frog 

3.0 Biology of the Green and Golden Bell Frog 

3.1 Habitat Types 

3.1.1 Natural Habitats 

3.1.2 Artificial Habitats 

3.2 Breeding 

3.3 Threatening Processes 

3.3.1. Habitat Loss and Degradation 

3.3.2 Other Processes 

4.0 Site Descriptions 

4.1 Bareena Wetland and Surrounding Areas 

4.2 Bell Frog Habitats at North Avoca 

4.3 Davistown Sites 

4.4 Bell Frog Habitats at Davistown 

4.3 Habitat assessments 

5.0 Surveys of Frogs, Tadpoles and Water Characteristics 

5.1 North Avoca 

5.2 Davistown 

6.0 Threats to Green and Golden Bell Frog populations 


6.2 Davistown 

7.0 Protection and Recovery of Green and Golden Bell Frog Populations 

7.1 Management Objectives 

7.2 Legislative Requirements and Compliance 

7.3 Recommendations for North Avoca Population 

7.4 Recommendations for Davistown Population 

8.0 Further Investigations 


8.2 Davistown 

9.0 Recommendations and Priorities 

10.0 References 




Appendices: 

Appendix 1 Description and justification for adopted specifications for the 

development of artificial pond breeding habitat for the Green and 

Golden Bell Frog. 

Appendix 2: Water/ Tadpole and Frog Surveys at North Avoca 

Appendix 3: Water/ Tadpole and Frog Surveys at Davistown 

Appendix 4: Monitoring Program at North Avoca and Davistown 

Appendix 5: Bush Regeneration Plan for Bareena Wetland. 

Appendix 6: Hygiene Protocol for the Control of Disease in Frogs (DEC 2000) 

List of Figures in Body of Report 

Figure 1: North Avoca Bell Frog Areas 

Figure 2: Bareena Wetland 

Figure 3: Habitats within the Bareena Wetland 

Figure 4: SEPP 14 Wetland and Swamp Oak Forest at North Avoca 

Figure 5: Green and Golden Bell Frog Habitat Areas. Bareena Wetland. 

Figure 6: Green and Golden Bell Frog Locations, East Davistown 

Figure 7: Ilumba Wetland and Easement 

Figure 8: Green and Golden Bell Frog Habitat Areas. East Davistown 

Figure 9: SEPP 14 Wetlands, Coastal Saltmarsh and Swamp Oak Forest at East 

Davistown. 

Figure 10: Seasonal Patterns in the Opening of Avoca Lagoon 

Figure 11: Land Zones around the Bareena Wetland. 

Figure 12: Land Zones at East Davistown. 

Figure 13: Bell Frog Habitat Enhancement Areas at East Davistown. 




List of Figures in Appendices 

Figure A1-1: Preferred Location of Bareena Bell Frog Breeding Pond. 

Figure A1-2: Schematic Profile of the Bareena Bell Frog Pond. 

Figure A1-3: Preferred Location of Ilumba Wetland Bell Frog Breeding Pond and 

Habitat Area. 

Figure A1-4: Schematic Profile of the Ilumba Wetland Bell Frog Breeding Pond 

and Habitat Area. 

Figure A5-1: Swamp Oak Forest, Bareena Wetland. 

Figure A5-2: Vegetation Zones, Bareena Wetland 

Figure A5-3: Paperbark Forest, Bareena Wetland. 

Figure A5-4: Weed Distribution and Density, Bareena Wetland. 

Figure A5-5: “No Mow” Areas and Sign Placement, Bareena Wetland. 




Plan of Management 

for the Green and Golden Bell Frog 

at North Avoca and Davistown . 

1.0 Executive Summary 

The Green and Golden Bell Frog was once abundant along the Central Coast of New 

South Wales but has undergone a significant decline here and elsewhere over the past 

forty years. It is now considered 'endangered' in New South Wales. Only two known 

populations of this species remain within this region, one at North Avoca and the other at 

Davistown, both within the Gosford Local Government Area (LGA). These populations 

are considered ‘key populations’ in the Draft Recovery Plan for the species. 

The present Plan of Management (POM), prepared on behalf of Gosford City Council, 

assesses threats to the long-term survival of these two populations in order to determine 

management options to improve the viability. It has been prepared in accordance with the 

recommendations and guidelines provided in the Draft Recovery Plan. 

The Green and Golden Bell Frog is an aquatic breeding species that generally requires a 

water body that is shallow (i.e.



increased salinity, and predation by introduced fish (i.e. Gambusia or Plague Minnow). 

Consequently, the viability of each of these populations could be greatly improved 

through habitat enhancement strategies that increase the area of available habitat 

(especially breeding habitat), reduces salinity in these areas, and excludes and or 

eliminates Gambusia. In addition, the current practice of opening Avoca Lagoon on 

demand to lower the water levels in it has a dramatic (and sometimes lethal impact) on 

Bell Frogs in the Bareena Wetland. Hence the timing and circumstances under which the 

lagoon may be opened needs to be subject to protocols that include its impact on the Bell 

Frog population at North Avoca. Bell Frogs may also be affected by increased incidence 

of chytrid fungal disease, predation by the introduced fox, and deposition of dog faeces, 

though these factors presently seem relatively minor in incidence and impact. 

Both the North Avoca and Davistown populations of the Green and Golden Bell Frog are 

likely to become extinct unless appropriate management actions are taken, as they are 

small in size and breeding habitat at both sites is limited and unreliable. The population at 

North Avoca is relatively low (i.e. about 100 adults) and relies on a single breeding site 

(i.e. Bareena Wetland) where conditions are often unfavourable. Opening of Avoca 

Lagoon to the ocean, and subsequent draining of Bareena Wetland, may eliminate an 

entire cohort of tadpoles. The population at Davistown is even lower (i.e. about 20 adults) 

and, though there is reasonably extensive potential breeding habitat here, conditions in 

these areas are seldom suitable for breeding. Salinity, which often or usually exceeds the 

threshold of 8 ppt for tadpole survival, restricts breeding for both populations. Gambusia 

is present at both North Avoca and Davistown and may invade ponds where the frogs 

might otherwise breed. At Davistown, further residential development could adversely 

affect the wetlands that occur there. 

In order to protect and enhance the two populations of the Green and Golden Bell Frog, 

recommendations have been made for the protection and enhancement of existing habitat 

and the creation of new, more secure breeding sites. It is recommended that existing 

habitat areas be protected from destruction, increases in average salinity, and invasion by 

Gambusia. This should minimize any ongoing population declines. It is also 

recommended that actions be taken to reduce average salinity levels and the abundance of 

Gambusia in existing breeding areas. These actions should increase the reliability of 

existing breeding habitat but would not increase the availability of such habitat, which is 

presently very limited. It is therefore recommended that new breeding and foraging 

habitat areas be developed at each site so that the availabilities of such habitats are 

increased. This should increase both reproduction and survival for the frogs and hence 

lead to increases in size and viability for each population. 

Ongoing monitoring of the frog populations is also recommended so that any impacts 

resulting in fluctuations in the frog numbers will be detected early and a suitable response 

made as quickly as possible. 

The deve lopment of new breeding and foraging habitat areas at North Avoca and 

Davistown is likely to be a compromise between the needs of the Green and Golden Bell 

Frog and other considerations. The most suitable way that new breeding habitat could be 




developed at North Avoca would be through earthworks in Avoca Lagoon adjacent to 

Bareena Wetland, but this area is already occupied by important and sensitive wetland 

(SEPP14 wetland containing Swamp Oak Forest); works in this area would be highly 

disruptive to the wetlands and are expensive. There is sufficient space, however, within 

the land between Bareena Wetland and nearby residential blocks for a small pond which 

could provide a little additional breeding habitat for the frogs and act as a refuge for 

tadpoles that may be rescued from the wetland (see below). The installation of this 

smaller pond is also fraught with difficulties as a suitable source of fresh water needs to 

be secured and the local community may not support a pond in this location. At 

Davistown, the most suitable way to create new breeding habitat for the frog would be to 

excavate and develop a number of ponds in the Illumba Easement. However, because of 

the presence of acid sulphate soil in this site, we have recommended the use of preformed 

artificial ponds (rather than soil-based ponds) that are only partly imbedded in the 

ground. 


2.1 Purpose of the Plan 

The specific objectives of the POM were as follows: 

1. Prepare a Plan of Management (POM) for the Green and Golden Bell Frog 

(Litoria aurea) in accordance with the recommendations and guidelines provided 

in the Draft Recovery Plan for this species (DEC 2005). 

2. Assess the threat factors influencing the long-term survival of the identified key 

populations within the Gosford LGA in order to determine management options 

to improve the species viability. 

3. Provide Gosford City Council with management guidelines, recommendations 

and procedures to ensure that the two extant populations are managed to improve, 

and if possible, expand the species habitat and improve the species viability in the 

Gosford LGA. 

The POM has also been prepared in accordance with the requirements for threatened 

species in the Local Government Act 1993. This includes identifying the category of 

lands identified as habitat for the species, objectives and performance targets for the plan 

with respect to the land, the means by which Council proposes to achieve the plan’s 

objectives and performance targets, and the manner in which Council proposes to assess 

its performance with respect to the plan’s objectives and performance targets. 

Accordingly, each land area is described in terms of its condition, the current and 

possible uses of the land, the nature of future permitted land uses, and the scale and 

intensity of likely future developments 

The Plan also complements the aims of the Draft Biodiversity Strategy developed by 

Gosford City Council. 




2.2 History of Green and Golden Bell Frog 

The Green and Golden Bell Frog was once a very common frog species that occurred 

along the coast of New South Wales from about Byron Bay in the north to the Victorian 

border, along the coast of north-eastern Victoria to about Lakes Entrance, and along the 

western slopes and Southern Highlands south from about Bathurst (Pyke and White 2001; 

White and Pyke 1996, 1999). Throughout much of this region it was the most frequently 

encountered frog and one that was familiar to many people (Pyke and White 2001). 

The Green and Golden Bell Frog was abundant along the Central Coast of New South 

Wales but has undergone a significant decline over the past forty years (White and Pyke 

1996). Various freshwater environments provided suitable habitat for this species and 

areas where this species occurred were widespread between Newcastle and Gosford. 

Today, it is known from only a handful of sites on the Central Coast, and from only from 

two sites within the Gosford LGA (White and Pyke 1996; see below). 

The Green and Golden Bell Frog has declined throughout its entire range and it is now 

considered at risk of extinction. It has disappeared from over 90% of the locations where 

it once occurred and populations have dwindled at many sites where it still occurs (Pyke 

and White 2001; White and Pyke 1996). It is presently considered endangered in New 

South Wales under the Threatened Species Conservation Act 1995, vulnerable in Victoria 

under the Endangered Species Protection Act 1992 and vulnerable nationally under the 

Commonwealth’s Environment Protection and Biodiversity Conservation Act 1999. 

This decline of the Green and Golden Bell Frog has been particularly severe along the 

Central Coast of New South Wales. Only two populations still remain in the Gosford 

LGA, one at North Avoca and one at Davistown; these populations are the subject of this 

management pla n (White and Pyke 1996). Other populations near Wyong, Pearl Beach, 

Umina, Ourimbah, Erina and elsewhere within the area have disappeared (White and 

Pyke 1996). 

A Draft Recovery Plan has been prepared by DEC for the Green and Golden Bell Frog in 

New South Wales (DEC NSW 2005). This plan considers aspects of the biology of this 

frog species and factors that threaten its populations, and formulates in general terms a 

strategy for the recovery of this species in New South Wales. The strategy aims to stop 

further losses and reverse the decline of extant populations. 

The Draft Recovery Plan identifies the need to protect and manage populations of the 

Green and Golden Bell Frog including the populations at North Avoca and Davistown 

(DEC NSW 2005). Both populations are identified in the Draft Recovery Plan as key 

populations. Action 11.3.4 of the Recovery Plan requires that a POM be prepared for 

nominated key populations. 

The present Plan of Management (POM) has been prepared in accordance with the 

recommendations and guidelines provided in the draft Recovery Plan. It aims to provide a 

strategy for achieving these goals. In addition, the POM considers the issues relating to 




land use and land tenure at these sites as well as taking into account the draft Biodiversity 

Plan being developed by the Gosford City Council. 

Green and Golden Bell Frogs are probably the best studied of all Australian frogs, but 

there are many gaps in our knowledge of this species (Pyke and White 2001). In 

preparing this management plan, information was obtained from a variety of sources. 

These sources include published and unpublished documents, the results of frog and 

tadpole surveys carried out at both North Avoca and Davistown over a number of years, 

and personal experience at other sites. These sources will be identified in the text below. 




3.0 Biology of the Green and Golden Bell Frog 

This overview of the biology of Green and Golden Bell Frogs is not comprehensive but is 

intended to highlight aspects of habitat requirements, behavior and ecology that are 

important in managing this endangered frog species. More comprehensive reviews of 

this biology have been published elsewhere (e.g. Pyke & White 2001; Pyke et al. 2002;). 

3.1 Habitat Types 

Habitat for the Green and Golden Bell Frog must include areas for breeding, foraging and 

sheltering. These habitat components may overlap or may be separated; they may be 

natural or they may be the result of human activity (i.e. artificial habitats). 

3.1.1. Natural Habitats 

Green and Golden Bell Frogs are aquatic breeding animals that generally require water 

bodies with the following features: 

In particular, it has been found that: 

• freshwater (i.e. low salinity) 

• shallow (i.e.



In addition, Green and Golden Bell Frogs are opportunistic breeders and habitat 

disturbance seems to be an important trigger as well as an essential feature of the 

breeding habitat of the Green and Golden Bell Frog (Pyke and White 1996; Pyke and 

White 2001; Pyke et al 2002). In natural environments, water levels in breeding sites may 

fluctuate greatly through evaporation and rainfall, and salinity may increase through 

intrusion of saltwater or decrease after rain. Various human activities, such as land filling 

or excavation, changes to drainage patterns or changes in water and soil chemistry may 

generate significant disturbance to water bodies. Disturbance, either natural or artificial, 

appears to be a common feature at sites where the Green and Golden Bell Frog breed 

successfully. 

It should be stressed, however, that the disturbance regime for successful reproduction is 

not well understood and is not correct to assume that any kind of disturbance will lead to 

enhanced breeding habitat or stimulate breeding (Pyke and White 2001). Further research 

is necessary to determine the array of suitable disturbance types. 

The characteristics of water in the breeding sites also determine the suitability of sites for 

breeding. Water temperature and salinity appear to be two important factors: tadpoles of 

the Green and Golden Bell Frog are able to tolerate a wide range of water temperatures 

and salinity but adults will generally only breed in water that is 20° or warmer and if 

salinity is less than 8 ppt (Penman 1998; Pyke and White unpubl; Pyke, Penman and 

White unpubl). Other water characteristics presently appear less important as Bell Frog 

tadpoles have been found in water with wide ranging levels of turbidity, dissolved 

oxygen and pH (Pyke and White unpubl). 

Green and Golden Bell Frogs utilize areas with little vegetation or areas with a low 

ground cover (i.e.



3.1.2. Artificial Habitats 

Conservation for most animal species requires protection of areas of natural habitat, and 

such habitat protection is generally preferable to attempting to artificially develop or 

enhance habitat. However, because some of the sites where the Green and Golden Bell 

Frog occurs are completely human-made, it should be possible to create artificial habitat 

that satisfies all the requirements for this species (Pyke and White 1996; 2001). Bell Frog 

breeding habitat has in fact been created at a number of other sites in New South Wales 

(e.g. Arncliffe, Homebush, Long Reef, Woonona,). This will not be possible for most 

animal species. 

However, not all attempts to recreate habitat for Bell Frogs have been successful and this 

is more likely to be successful if it occurs where the species is already present and were 

suitable breeding habitat already exists. (White and Pyke 2005). At several sites where 

this frog species already occurs, it has proven possible to develop new ponds that have 

been colonized and used for breeding. Many of the recreated habitat areas that were not 

colonized by Bell Frogs were located in areas where Bell Frogs were not already present 

(i.e. the frogs had to either move or be moved to the new habitat areas). Translocating 

frogs to newly-created habitat areas seems to greatly increase the chance of failure of 

these habitat areas. 

Based on observations of the Green and Golden Bell Frog under both natural and 

artificial conditions, specifications for the development of artificial breeding habit at have 

been produced (Pyke and White 1996, 2001; White unpubl; see Appendix 1). Further 

research may alter these specifications. 

3.2 Breeding 

Breeding by the Green and Golden Bell Frog occurs mostly during the spring and 

summer (Pyke and White 2001). Males call mostly at night, often following rain. They 

generally call while floating in water, sitting on the ground next to the water, or perched 

on something above and/or near the water. Eggs are laid in the water and are seldom 

encountered outside of spring and summer. Tadpoles are also mostly encountered during 

spring and summer, but they sometimes remain as tadpoles during winter and do not 

metamorphose until the following spring. 

3.3 Threatening Processes 

Threatening processes can be any activity or organism that decreases the likelihood of 

survival of Green and Golden Bell Frogs (White and Pyke 1996; Pyke and White 2001). 

Some threatening processes are recognized by NSW legislation; two such processes 

(Gambusia and Chytrid) have been recognized specifically for Green and Golden Bell 

Frogs under the Threatened Species Conservation Act 1995 (e.g. NSW NPWS 2002; see 

below). Additionally, this species may, along with other frog species, be adversely 

affected by clearing of native vegetation, removal of ground timber, alterations to 




hydrological regimes, predation by the introduced fox, water pollution and anthropogenic 

climate change. 

3.3.1. Habitat Loss & Degradation 

Like most other threatened species, the processes that have undoubtedly 

contributed most to the decline of the Green and Golden Bell Frog have been 

habitat loss and degradation (White and Pyke 1996; Pyke and White 2001). 

Many of the coastal wetlands where this species once occurred have been 

replaced or greatly modified by various kinds of human development. 

Gambusia or Plague Minnows : 

Introduction of the fish Gambusia has also contributed greatly to the decline 

of this frog species (Pyke and White 1996, 2000, 2001; White and Pyke 

1996). This small fish, which was introduced from North America into 

Australia to control mosquitoes and the diseases they carry, is a voracious 

predator of the eggs and tadpoles of the Green and Golden Bell Frog and other 

frog species (Pyke and White 1996), and are now widespread in eastern 

Australia. A high density of Gambusia in freshwater sites often means that 

Bell Frogs lose all or most of their tadpoles to these fish. If the density of 

Gambusia is high enough, Green and Golden Bell Frogs may not be able to 

breed at all in the water body. The presence of G ambusia has been strongly 

linked to the disappearance of the Green and Golden Bell Frog at many sites 

(White and Pyke 1996) and, for this reason, it is illegal in NSW to promote 

the spread of Gambusia into areas where Green and Golden Bell Frogs may be 

present. 

Chytrid: 

Chytrid fungal disease (or chytridiomycosis) may also be a threat to the Green 

and Golden Bell Frog, though its importance is unclear (Pyke and White 

2001). Though it has only been in Australia since the 1970s, it has been found 

to be present in some populations of this frog species and has been implicated 

in the declines of some other frog species (Berger et al. 1999). Chytrid is a 

frog disease caused by tiny water-borne fungal cells that enter frog skin (while 

they are tadpoles) and begin to break down structural proteins (keratin) in the 

deeper skin layers. This process continues until the deeper layers have been 

killed (and skin sloughing occurs). Other visible symptoms include the 

eruption of blood spots in the finger and toe joints and blotchy discolourations 

in the skin. Chytrid is fatal. It is illegal to undertake activities that may 

facilitate the spread of chytrid spores from water body to water body or from 

frog to frog. This is particularly pertinent threatening process as it determines 

how frog surveys and frog handling may or may not be carried out. 




Other Processes 

Other processes that may threaten the Green and Golden Bell Frog are 

predation by the introduced fox and other exotic predators, wetland drainage 

and water pollutio n (DEC NSW 2005; Pyke and White 2001). However, with 

the possible exception of water pollution, none of these factors is apparently 

significant (Pyke and White 2001) at either North Avoca or Davistown. Since 

frog breeding areas are close to residential blocks at both locations, the water 

in them could be polluted through urban runoff, dog faeces or chemical 

introduction. 

For recovery of the Green and Golden Bell Frog, it will be necessary in 

general to protect and enhance corridors of habitat suitable for movements 

between areas used by the frogs (DEC NSW 2005). However, this does not 

appear to be a significant issue for either of the two present populations. In 

both cases, the frogs are able to carry out all their normal activities using 

adjacent habitats. The qualities of these habitats are important and there are 

few apparent impediments to movement between them. 




4.0 Site Descriptions 

In terms of frog habitat, and the frog species that use this habitat, North Avoca and 

Davistown are reasonably sim ilar and differ quantitatively rather than qualitatively. 

Detailed descriptions of the available habitat at these two sites can also be found in 

Bannerman (1998). 

4.1 Bareena Wetland and Surrounding Areas 

The Bareena Wetland is an artificial wetland at the eastern edge of Avoca Lagoon near to 

where it exits (occasionally) to the ocean (Figures 1 and 2). This wetland was created 

many years ago, either in the early 1980s when a sewer pipe was laid across the southeast 

corner of Avoca Lagoon, the pipe was buried and a wall of earth and rocks was formed 

(Consterdine 1999a) or in about 1950 when a levee bank was constructed to hold 

flooding lagoon waters back from an adjacent caravan park that occurred there at the time 

(Consterdine 1999b). This wall, which now forms a linear boundary to the wetland on its 

western edge (Figure 2), trapped freshwater between it and the higher ground to the east. 

The wall is permeable to water and hence allowed salty water from the lagoon to get into 

the wetland and so, over time, a brackish wetland formed behind the wall. Because of this 

permeability of the wall to water, the water levels in the lagoon and wetland are generally 

the same and changes in water level in the lagoon are quickly followed by matching 

changes within the lagoon (Consterdine 1999a; see below). In addition, there are a few 

open storm-water drains in the area near the wetland and some of the nearby residential 

blocks of land contain small artificial ponds. 

Bareena Wetland is roughly rectangular in shape, occupies an area of about 0.3 ha and 

has three distinct regions within it (Figure 3). The southern half is almost all open water; 

in the northern corner there is an area of low open forest dominated by Melaleuca 

quinquenervia with almost no understorey; and in between these two areas there is an 

area of emergent reeds (Phragmites australis). The areas of reeds and open water receive 

almost full sunshine. The water and/or ground in the forested areas are partly shaded. To 

the west and south of the wetland, between it and the lagoon, the vegetation is generally 

low, open forest dominated by Casuarina glauca. 

Running along the eastern edge of Avoca Lagoon between the lagoon and nearby 

residential blocks of land along Bareena Avenue and Lake Street is a strip of land that 

includes remnants of original vegetation but is maintained as an area of urban parkland 

(Figure 3). We refer to this area and the contiguous and adjacent urban yards as the 

“nature strip”. To the east and north of this nature strip there is an extensive urban area, 

consisting of roads, houses, mown grass and gardens. 




Figure 1 

North Avoca and Bareena Wetland 

The Nature Strip extends for about 300m between Avoca Lagoon at its southern end and 

Tramway Street at its northern end (Figure 1). It is bounded by Bareena Wetland and 

Avoca Lagoon to the west and the houses along Bareena Avenue and Lake Street to the 

east, varies in width from about 10m to about 30m and is maintained as an area of urban 

parkland, consisting mostly of mown grass with occasional trees, clumps of thick shrubs 

(mostly Lomandra longifolia), and some unmown areas dominated by low, spreading 

weeds such as Nasturtium sp. and Paspalum sp. 




Figure 2 

Bareena Wetland 




Figure 3 

Habitats within the Bareena Wetland and Surrounds 




Several urban yards, not contiguous with the nature strip, have been included over 

different periods of time in the regular surveys (Figure 1). All of these yards contain areas 

of pavement and mown grass, and none of these were home to cats or dogs at the time 

that they were surveyed. At 18 Bareena Avenue, there is a small area (i.e. about 5m x 

5m) containing several well-established, very thick and sometimes contiguous clumps of 

Lomandra longifolia. In the adjoining block (i.e. 22 Bareena Avenue) there is an area of 

low shrubs, shaded by small trees. The garden at 37 Lake Street contains many shrubs 

that are relatively thick, especially near their bases, including Lomandra longifolia, 

Strelitzia regina and large bromeliads. The gardens in the adjoining blocks (i.e. 35 & 39 

Lake Street) contain relatively few shrubs but do include a small number with similar 

growth form (i.e. Lomandra longifolia, Strelitzia regina, Yucca sp. and Sansevieria sp.). 

The garden at 22 Ocean Street contains an artificial pond with emergent reeds as well as 

some thick shrubs (i.e. Lomandra longifolia). The garden at 12 Lake Shore Drive 

contains a small, artificial pond and many shrubs with thick bases (i.e. Lomandra 

longifolia, Amomum sp.). 

4.2 Bell Frog Habitats at North Avoca 

Breeding Habitat 

Frog breeding habitat at North Avoca is very limited and appears to be confined to the 

Bareena Wetland which is suitable in some respects as a breeding site for the Green and 

Golden Bell Frog. It is of moderate size (i.e. between 0.1 and 1.0 ha), shallow (i.e.



Green and Golden Bell Frog shelter habitat probably extends to other areas of Avoca 

Lagoon. Bell Frogs have, in particular, been recorded from sites at Lake Shore Drive, 

near the northern end of Avoca Lagoon. A creek enters the lagoon near this point and 

there is suitable foraging and shelter habitat in the area. Breeding habitat, however, does 

not appear to be available there. 

Foraging Habitat 

Foraging habitat is also diverse at North Avoca. Some foraging habitat is available within 

the wetland, but the majority occurs outside. Bell Frogs feed on a wide variety of 

invertebrate animals and may traverse a wide range of habitats in order to find prey. 

Foraging areas at Bareena Wetland include the tussock vegetation around the wetland, 

but also the overgrown grassed areas along the nature strip and in the backyards of 

nearby houses. 

Overwinter Habitat 

Overwinter habitat appears to be relatively limited. The base of the wetland can provide 

overwinter habitat, but only when the wetland contains fresh water. Otherwise overwinter 

habitat appears to consist of backyard sheds, timber piles and other solid ground cover 

items, none of which are at all common. 

Figure 4 indicates the areas currently designated as SEPP 14 wetland or that contains 

vegetation communities that are likely to qualify as endangered ecological communities 

(i.e. 40a as Freshwater Wetlands on Coastal Floodplains, 40b as Swamp Oak Floodplain 

Forest and 37ei as Swamp Sclerophyll on Coastal Floodplains). 




Figure 4 

SEPP 14 Wetland and Vegetation Communities at North Avoca 

Legend E37ei = Coastal Sand Swamp Forest 

E40a = Phragmites Rushland 

E40b = Estuarine Baumea Sedgeland 

Source: Bell (2004) 




Figure 5 

Green and Golden Bell Frog Habitat Areas, North Avoca 




4.3 Davistown Sites 

The Davistown sites are more scattered than was the case at North Avoca. All of the sites 

are on low-lying land that may be subjected to some saline influences. 

There are three wetland areas that are considered to be Bell Frog habitat: one that lies 

between Magnolia and Ilumba Avenues to the south of Kincumber Crescent; and two that 

lie between Ilumba Avenue and the rest of Kincumber Crescent as it arcs around to the 

south to and beyond its intersection with Romford Close. We refer to these as the 

Magnolia, Ilumba and Romford wetland areas respectively (Figure 6). 

Figure 6 

Green and Golden Bell Frog Locations, East Davistown 




Magnolia Wetland is presently a brackish wetland area containing Juncus .sp. reeds, 

Bolboschoenus caldwellii and mangrove species including Avicennia marina (Grey 

Mangrove) and Aegiceras corniculatum (River Mangrove). Landward migration of the 

Mangroves has been occurring on this site and some saltmarsh species including 

Sporobolus virginicus (Salt Couch) and Sarcocornia quinqueflora (Samphire) occur to 

the north-western corner. Fringing vegetation consists of an open Melaleuca sp. 

(Paperbark) and Casuarina glauca (Swamp Oak) forest (GCC, 1992) and open grassland. 

Ephemeral water bodies accumulate on this wetland from urban runoff and direct rainfall 

and reach a maximum depth of 50 cm. Seawater inundation is also evident via the culvert 

beneath Kincumber Crescent to the north. However, at present the southern end of the 

site remains above sea level and does not appear to openly connect to Cockle Channel 

even during periods of heavy rain. Refuge and shade for frogs is provided by vegetation 

and litter on the site as well as by gardens in surrounding properties. Water pollution on 

the site appears to be minimal and an analysis of the soil revealed a highly saline, sandy 

substrate. 

Ilumba Wetland contains a closed Melaleuca forest with surrounding open grassland. 

Shallow, ephemeral, freshwater ponds have occurred on this site after heavy rain from 

urban runoff and rainfall. The soil was found to be sandy with a high degree of salinity. 

Shade and refuge are provided on site by the vegetation and by gardens and shade houses 

in adjacent properties. Little evidence of water pollution has been apparent. 

Romford Wetland contains a predominantly saline wetland ecosystem that occurs on 

saline, sandy soil and consists mostly of saltmarsh and mangrove species. An open 

Swamp Oak forest containing some Juncus sp. and grassland also occurs around the 

fringes of the site. Permanent water bodies exist across the wetland resulting from 

seawater inundation, rainfall and urban runoff. Ponds have reached a maximum depth of 

60 cm and evidence of water pollution from toxic wastes and litter has been found. Car 

dumping has been observed on the site. Shelter and shade are provided by the fringing 

vegetation and by litter including broken concrete and car bodies. 

It is therefore apparent that each of these wetlands is quite heterogeneous with areas of 

open water, stands of Casuarina glauca, low saltmarsh areas, isolated mangroves areas, 

and small areas of sedges and reeds. The presence of saltmarsh and mangroves is 

indicative of the relatively salty conditions. The presence of sedges and reeds indicates 

less salty conditions. All of the wetlands contain areas of Swamp Oak Forest and some 

small pockets of Coastal Saltmarsh are also present. 

The Ilumba Wetland has a cleared western easement (Figure 7), between the Swamp Oak 

Forest and residential lots facing Ilumba Avenue. This area, which we refer to as the 

Ilumba Easement, is mostly grassed, although at its southern end sedges become more 

common. It is maintained by Gosford City Council and adjoins a vacant lot that is also 

owned and maintained by Council. This lot has a drainage line through it and provides a 

vegetated link to Illumba Avenue which separates the Magnolia and Ilumba Wetlands 

and across which frogs would be expected to travel to forage. 




Figure 7 

Ilumba Wetland and Easement 

4.4 Davistown Bell Frog Habitat Areas 

Breeding Habitat 

There is very little specific information about frog breeding habitats at Davistown as 

there have been relatively few observations of tadpoles or juvenile frogs; in addition, the 

general frog survey information for Davistown is inadequate. The following descriptions 

of frog habitat at Davistown include observations and information provided by residents, 

herpetologists familiar with the area and the limited survey data, as a result the 

descriptions are somewhat general in nature. 

Available frog breeding habitat at Davistown appears to be quite limited. Areas of 

reasonably fresh water are known to have occurred at Davistown in the past but these 

low-lying sites have mostly been filled in as the demand for residential land has 

increased. Prior to the expansion of residential development at Davistown, Bell Frogs had 




been observed breeding in flooded ditches and grassy depressions in areas that have now 

been built upon. 

As Davistown is a very low-lying area that is largely surrounded by sea-water, large areas 

of land and local drainage lines regularly receive salty water. This is tidal in some places. 

Hence the remaining areas of wetland are generally brackish or salty, although small 

depressions in the wetlands may hold fresh water long enough for successful breeding. 

Alongside some of the roads there are open gutters as well as some urban yards that 

contain small artificial ponds that could be used as breeding sites. These appear to be the 

last remaining potential breeding habitats available, although it is possible that smaller, 

ephemeral breeding sites occur in the larger wetland areas. In some parts of the wetlands, 

freshwater remains for some time after rain and in these areas beds of reeds have 

developed. However, these sites also contain fish (including Gambusia) and the water 

quickly becomes salty. 

Observations indicate that the Green and Golden Bell Frogs have occasionally been able 

to breed under existing conditions at Davistown. Immature frogs have been observed by 

local residents and found during surveys in 2005 in unsealed road gutters along Magnolia 

Avenue. Bell Frogs have occasionally been heard calling, also by local residents, from 

within Magnolia Wetland. Juveniles and mature frogs were recorded on a number of 

survey nights in 2005. Tadpoles were also recorded in 2005 and a number collected by 

the Australian Reptile Park for a captive breeding program (see Appendix 3 below). 

Shelter Habitat 

Shelter habitat is readily available in all of the three wetland sites and in nearby areas at 

Davistown. The wetlands contain dense vegetation that provides protection against 

predatory birds. The grassed areas between the residential lots and the wetlands are 

overgrown in places and also provide adequate shelter sites for Bell Frogs. In moving 

between shelter sites in the wetland and in urban backyards, Bell Frogs must occasionally 

cross areas of open lawn and roads. 

Foraging Habitat 

Foraging habitat also appears to be readily available at Davistown. There are several 

areas where low or very low vegetation occurs that could be used as foraging habitat. 

Most of these areas are associated with grassed, overland floodways, stormwater 

channels or drains. The grassed areas between the residential lots and the wetlands are 

also suitable as foraging areas. In addition, gardens in many of the houses near the 

wetlands provide additional shelter vegetation. 




Figure 8 

Green and Golden Bell Frog Habitat Areas, East Davistown 




Over-winter habitat 

Over-winter habitat appears to be scarce in the wetlands. Apart from an occasional fallen 

tree, there is very little reliable cover and few or no fresh water areas that could be used 

during winter. Over-wintering may occur under backyard sheds, timber piles and other 

solid items in the residential areas. 

Figure 9 

SEPP14 Wetland, Coastal Saltmarsh and Swamp Oak Forest, East Davistown 

Legend 

E40i = Estuarine Swamp Oak Forest 

E43ai = Estuarine Paperbark Scrub -Forest 

E47 = Estuarine Mangrove Scrub 

E47a = Estuarine Saltmarsh / Grassland 

Source: Bell (2004) 




4.5 Comparison of Available Habitat at North Avoca and Davistown 

There is generally more available habitat, including breeding habitat, for Green and 

Golden Bell Frogs at Davistown than at North Avoca. However, suitable breeding 

conditions at Davistown occur much less often than at North Avoca. Each of the wetlands 

at Davistown is larger than the single wetland at North Avoca and the areas of shelter and 

foraging habitat are similarly larger at Davistown. The areas of urban gardens and yards 

around the Davistown wetlands are also larger than the similar area near Bareena 

Wetland at North Avoca, as much of the area around Bareena Wetland consists of Avoca 

Lagoon. Despite this, the wetlands at Davistown are generally saltier than Bareena 

Wetland and consequently conditions within these wetlands which are suitable for frog 

breeding occur much less often than at North Avoca (see Figures 5 and 8). 




5.0 Frog, Tadpole and Water Characteristics Surveys 

Summaries of results for the surveys at North Avoca and Davistown are presented below. 

More detailed results are presented in the appendices (North Avoca: Appendix 2; 

Davistown: Appendix 3). 


At North Avoca, a total of eight frog species have been recorded (Table 1), with the 

Green and Golden Bell Frog being one of the relatively abundant species. The most 

abundant species at North Avoca is the Striped Marsh Frog. 

Table 1 

Frogs Detected at Bareena Wetland 

1998-2005. 

Species 

Number 

males 

recorded 

calling 

Number 

tadpoles 

captured 

Number 

immatures 

captured 

Number 

adult 

captures 

2 

Crinia 4 0 0 0 

signifera 

Limnodynastes 75 72 15 32 33 

peronii 

Litoria aurea 31 51 90 356 22 

L. caerulea ? 1 0 0 2 0 

L. dentata 8 12 2 2 0 

L. fallax 1 0 0 3 0 

L. peronii 5 0 0 3 0 

L. tyleri 6 0 0 1 0 

Notes: 1. Recorded calling once in wetla nd but number not estimated 

2. Includes recaptures 

Number 

frogs 

observed 

but not 

captured 

Tables A2.1 and A2.2 (in Appendix 2) provide a summary of survey dates and survey 

duration. 

The survey results indicate the following with regard to the population of the Green and 

Golden Bell Frog at North Avoca: 

- The population size is low (i.e. about 100 adults on 

average). 




- There appears to be only one breeding location (i.e. 

Bareena Wetland) where successful breeding has occurred, 

as judged by the production of juvenile frogs. Breeding has 

occurred in only three out of the seven years during which 

surveys have taken place (Table A2.4) 

- Frogs may be found near garden ponds but have not been 

recorded breeding at any of these ponds 

- When breeding has been successful, a small to moderate 

number of new recruits probably entered the adult 

population (see Appendix 2 for more detail) 

- Breeding success has been limited by the high frequency 

(about 65% of the time) with which salinity in the wetland 

has been marginal or too high (i.e. approaching or 

exceeding 8 ppt: Penman 1998). During spring and summer 

surveys salinity exceeded the critical threshold of 8 ppt on 

31% of occasions and has been in the range 6-8 ppt another 

34% of the time. 

- In order to forage and find shelter, the frogs appear to move 

about an area that includes the mown area around the 

wetland and the yards associated with adjacent and nearby 

houses. 

5.2 Davistown 

The recorded frog fauna at Davistown is similar to that at North Avoca with a total of six 

species having been detected during the survey period (Table 2). The six species at 

Davistown also occur at North Avoca. One species, the Eastern Dwarf Tree Frog Litoria 

fallax, was not recorded at Davistown until 2005. Once again, the Striped Marsh Frog is 

probably the most abundant frog species. 

Table 2 

Frogs Detected at Davistown 

Species Date Location Lifestage How detected Observer(s) 

Green and 

Golden 

Bell Frog 

Bleating 

Tree Frog 

31/3/1998 

7/2/2002 

25/12/02 

10/3/2003 

24/3/2003 

8/2/2004 

17/2/2005 

23A Magnolia 

Romford Wetl 

1 Ilumba Ave 

1 Ilumba Ave 

1 Ilumba Ave 

28 Ilumba Ave 

16/21/25 

Magnolia Ave 

Adult 

Adult 

Adult 

Adult 

Adult 

Adult 

Adult + 

tadpoles 

Observed 

Observed 

Observed 

Observed 

Observed 

Observed 

Observed 

13/10/98 30 Magnolia Adult Observed G. Pyke 

G.Pyke, R. Wellington 

P. Shelley 

M and D McGinlam 



Several 

Several 




Bleating 

Tree Frog 

Common 

Eastern 

Froglet 

Eastern 

Dwarf 

Tree Frog 

Green 

Tree Frog 

Striped 

Marsh 

Frog 

Striped 

Marsh 

Frog 

8/12/1998 Magnolia 

Wetland 

4/6/1998 Magnolia 

Wetalnd 

Dec 2005 

Adult Calling G. Pyke; 

M. Bannerman 

Adult Calling G. Pyke 

North of RSL 

Club. Adult Obsrved A, Mucci 

13/10/98 30 Magnolia Adult Observed G. Pyke 

13/10/98 30 Magnolia Adult Observed; 

Captured 

G. Pyke 

2/04/2003 1 Ilumba Ave Adult Observed G. Pyke; 

A. Mucci 

The above survey results and opportunistic observations indicate the following with 

regard to the population of the Green and Golden Bell Frog at Davistown: 

- The population size is small (i.e.



6.0 Threats to Green and Golden Bell Frog populations 


The above surveys indicate that the Green and Golden Bell Frog population at North 

Avoca is likely to be affected by the following factors: 

Disturba nce of Bareena Wetland 

Because Bareena Wetland is the only known breeding 

location for the Green and Golden Bell Frog at North 

Avoca, disruptions to it may adversely impact this frog 

population and should therefore be viewed as cause for 

concern. As Bell Frogs are a colonising species, certain 

types of disturbance may promote habitat use by the frogs 

(e.g. increases in water level following periods of low 

water level, decreases in salinity after periods of high 

salinity and sudden decreases in the area covered by 

emergent vegetation), while other changes may be harmful 

(e.g. prolonged high salinity levels, insufficient fresh water, 

constant water levels, introduced predators). 

Bareena Wetland may be affected in the future by the 

following: 

q 

q 

q 

q 

q 

q 

q 

q 

Changes to water level in adjacent Avoca 

Lagoon (e.g. through flooding or release of 

water) 

Invasion by the fish, Gambusia 

Increases or decreases in prevalence of 

chytrid fungus or other diseases 

Water pollution (including ammonia buildup 

from dog faeces) 

Fire and fire control 

Dumping of rubbish 

Dumping of grass cuttings or vegetation 

Loss or addition of vegetation within or 

adjacent to it (e.g. weed invasion, slashing/ 

mowing) 




Lagoon Openings 

To reduce the effects of flooding on properties adjacent to 

Avoca Lagoon, the lagoon is opened to the ocean by 

Gosford City Council whenever water levels approach or 

reach threshold levels. After water drains from the lagoon, 

a matching decrease occurs in the water level within the 

Bareena Wetland. If the water level in the lagoon falls by 

more than 1.4 metres, Bareena Wetland may become dry. If 

the lagoon is slightly above this level, the wetland retains 

water but it is too salty for frogs and tadpoles. The lagoon 

will not become usable for Bell Frogs until rain water raises 

both the level of the lagoon and the wetland, and dilutes the 

salt concentrations down to levels where frogs and tadpoles 

(i.e. below 8 ppt) can survive. 

The controlled loss of water from the wetland, as a result of 

draining the lagoon, may have either a positive or negative 

effect on the frogs, depending primarily on when it occurs. 

If lagoon opening occurs when tadpoles are present in the 

Bareena Wetland, the tadpoles will probably die as a result 

of the changes in water and salinity levels. If it occurs 

during spring or summer, when conditions are suitable for 

frog breeding, the entire breeding season may be lost. If it 

occurs during autumn or winter, and no Green and Golden 

Bell Frog tadpoles are present, then little adverse impact 

should occur; the impact might even be beneficial through 

the disturbance that results from drying up of the wetland. 

Green and Golden Bell Frogs readily recolonise pond sites 

that have become dry and later filled with water (Pyke and 

White 2001). Thus, the drying of the pond for a short 

period can facilitate breeding later in the year. 

Opening of Avoca Lagoon occurs reasonably often and, 

given the seasonal pattern of times when it is opened, the 

effects of this will mostly be negative as far as the Green 

and Golden Bell Frog is concerned. Avoca Lagoon has 

been opened on average 1.6 times per year with 14 

openings over the eight-year period from 1998 to 2005 

(Fig. 10) and 30 over the 20-year period from 1976 to 1995 

(Consterdine 1999). Some (i.e. 3 of 14) openings during the 

more recent period have occurred during spring-autumn 

period which is when tadpoles of the Green and Golden 

Bell Frog are most likely to occur (Fig. 10). 




Figure 10 

Seasonal Patterns in the Opening of Avoca Lagoon 

9 

8 

7 

6 

COUNT 

5 

4 

3 

2 

1 

0 

1_Spring 

2_Summer 

3_Autumn 

SEASON 

4_Winter 

Invasion by Gambusia 

Invasion of Bareena Wetland by Gambusia is likely to 

adversely affect the Green and Golden Bell Frog. 

Gambusia are known to prey upon the eggs and tadpoles of 

Green and Golden Bell Frogs (White and Pyke 1999) and 

predation by this species is listed as a Key Threatening 

Process for Green and Golden Bell Frogs under the 

Threatened Species Conservation Act 1995. As the adjacent 

Avoca Lagoon contains Gambusia (e.g. Consterdine 1999b; 

personal observations), invasion of the wetland by this fish 

species remains a constant threat. A strategy should 

therefore be adopted which will minimize this likelihood 

and eliminate this fish if invasion does occur. Gambusia 




Chytrid Fungus 

Pollution of Wetland 

Other Factors 

cannot survive for long out of water and so the controlled 

emptying of Avoca Lagoon during the winter months may 

also be an effective measure to prevent Gambusia from 

colonizing the Bareena Wetland. 

Chytrid fungus is known to have been present within the 

North Avoca population of the Green and Golden Bell 

Frog, but the current level of infection within the 

population is unknown. Increases in the infection rate could 

be detrimental to the population, while decreases could 

have the opposite effect. Other diseases could similarly 

affect the population. It is known that chytrid spores are 

killed by exposure to salt and it is possible that the 

fluctuating salinity levels in the Bareena wetland attenuate 

the impact of chytrid on this population of Bell Frogs (see 

Figure 2-2). 

Though the effects of pollution on the Green and Golden 

Bell Frog are unknown, precaution would suggest that any 

pollution of Bareena Wetland should be avoided as much 

as possible. Such pollution could arise through accidental 

or deliberate introduction of various chemicals, including 

fertilizers, herbicides or insecticides. It could also arise 

through the influx of urban runoff, which typically carries a 

number of pollutants including detergents and organic 

solvents. It could also arise through the introduction of 

ammonia that is released from dog faeces as they 

decompose (Schuytema and Nebeker 1999; also see 

Appendix 2). The effects of any kind of water pollution are 

likely to be greatest when the water level in the wetland is 

low. 

Fire and its control within the wetland area are likely to 

have adverse impacts on frogs through killing frogs that are 

sheltering in the vegetation, destruction of such sheltering 

habitat, and possibly the introduction of chemical fire 

suppressants. These activities should be avoided. 

The dumping of rubbish is unlikely, unless it became 

extreme, to have a significantly adverse impact on the 




wetland and its frogs. However, it should be controlled 

because it creates an unsightly appearance, demeans the 

conservation value of the area, is illegal and encourages 

rodents (and their predators) into the area. Fallen timber 

and logs should be left on the ground or placed in small 

heaps away from public areas as these can be used as 

overwinter sites by the frogs. 

Potential or proposed changes to the vegetation may have 

positive or negative effects on the frog habitat in the 

wetland. In general, negative effects are likely if there is an 

increase in shade, a decrease in the extent of open water, or 

a decrease in the amount of thick low vegetation. The Bush 

Regeneration Plan for the Bareena Wetland (Appendix 5) 

includes recommendations for removing unwanted plant 

species and replacing them with vegetation that is native to 

the area and can enhance the habitat value of the wetland 

for Green and Golden Bell Frogs. 

Changes in average salinity within Bareena Wetland 

Salinity levels in the Bareena Wetland have fluctuated 

considerably (see Table A2-5 in Appendix 2) and are likely 

to continue to do so through variation in rainfall, movement 

of ground water and evaporation. However, there may also 

be changes to the average salinity with consequent changes 

in breeding and population size for the Green and Golden 

Bell Frog. 

If the average salinity within this wetland habitat were to 

increase, a decrease in the frequency of conditions suitable 

for frog breeding would be expected. This would lead to 

reduced recruitment into the population with subsequent 

decline in population size. As the population is already low, 

this could lead to the extinction of the local population of 

Green and Golden Bell Frogs. 

The average salinity within this wetland could increase, in 

the short-term, through changes in the pattern of water 

drainage that either increase the influx of saltwater or 

decrease the influx of freshwater. Such effects could arise 

from any earthworks in or around this wetland or from 

nearby urban development that diverts more rainfall runoff 

into the stormwater system. 




Conversely, measures that decrease average salinity in the 

wetland by increasing the amount of freshwater entering 

the wetland (particularly following local rainfall events) are 

likely to increase the number of opportunities for breeding 

and likely to assist with the survival of Bell Frog tadpoles. 

However, turning the Bareena Wetland into a totally 

freshwater wetland is undesirable as this can also lead to a 

reduced use of the site by Bell Frogs. 

6.2 Davistown 

The above surveys indicate that the Green and Golden Bell Frog population at Davistown 

is likely to be affected by the following factors: 

Loss or disturbance of we tland habitat; 

It is apparent from past and recent observations that 

breeding by the Green and Golden Bell Frog has occurred, 

within the wetland areas that lie between Magnolia Avenue 

and the end of Kincumber Crescent near Romford Close. 

Not all breeding sites have been identified at Davistown 

and only the 2005 site has a precisely known location. 

Other potential breeding sites appear to be present within 

these wetland areas and any future loss or disturbance of 

this wetland habitat must be regarded as a threat to its 

population. Without breeding habitat, even if it is only 

occasionally suitable, the population must decline to 

extinction. 

As parts of the wetland areas are zoned for residential 

development, loss or disturbance of wetland habitat as a 

result of residential development could occur in the future. 

Ideally, these areas should be rezoned to prevent their loss 

or degradation as habitat areas. 




Increases in average salinity within this wetland habitat 

If the average salinity within this wetland habitat were to 

increase, a decrease in the frequency of conditions suitable 

for frog breeding would be expected. This would lead to 

reduced recruitment into the population with subsequent 

decline in population size. As the population is small, this 

would probably lead to extinction. 

The average salinity within these wetland areas could 

increase, in the short-term, through changes in the pattern 

of water drainage that either increase the influx of saltwater 

or decrease the influx of freshwater. Earthworks, including 

kerb and guttering, around these wetland areas could have 

such effects. Average salinity could also increase through 

heightened sea levels that are likely to occur as a result of 

long-term climate changes. 

Increases in distribution and/or abundance of Gambusia 

within these wetland areas. 

Gambusia is known to prey heavily on eggs and tadpoles of 

frogs, especially the Green and Golden Bell Frog, and has 

been linked with the decline in this species. Any increase in 

the distribution and/or abundance of Gambusia is therefore 

likely to decrease recruitment into the population of this 

frog species and hence to increase the likelihood of its 

decline to extinction. 

Changes to the patterns of water flow in or around the 

wetland areas could increase the d istribution of Gambusia 

through facilitating its movement from one area to another. 

It is not known what factors controlled the abundance of 

this fish in places where it occurs. 

It should be possible, however, to have positive effects on the population through the 

following measures: 

- 1. Development of new habitat that is suitable for breeding 

As described above, given an appropriate recipe (see 

Appendix 1), it should be possible to create suitable more 

secure breeding habitat for the Green and Golden Bell Frog 

at Davistown. 




Several candidate sites for such habitat development are 

discussed below (Section 7.4). 

- 2. Artificial changes to water drainage patterns that 

increase the frequency of water with sufficiently low 

salinity for frog breeding, while avoiding or limiting the 

presence of Gambusia in the water. 

A potential strategy for achieving this is discussed below 

(Section 7.3). 




7.0 Protection and Recovery of the Green and Golden 


The current Plan is based on the recognised threats (Section 6.0) to the Bell Frogs at 

North Avoca and Davistown and considers the various measures that could be adopted to 

help overcome or ameliorate these threats. Detailed and comprehensive discussions of 

how protection and recovery of the Green and Golden Bell Frog populations at North 

Avoca and Davistown might be achieved can also be found in earlier reports prepared by 

Bannerman (1998) and Consterdine (1999a, b). Many of these issues have been 

incorporated into this Plan of Management. 

7.1 Management Objectives 

This management plan aims: 

To Maintain Existing Populations of Green and Golden Bell Frogs at North Avoca and 

Davistown. 

v The two populations, at North Avoca and Davistown, are small and are faced with 

many impacts that threatened the viability of both populations. The primary 

concern is to ensure that these populations can survive in the wild. 

The key issues affecting the ongoing survival of Green and Golden Bell Frogs at North 

Avoca and Davistown are described in Section 6. The following objectives upon which 

the recommendations contained within this study are based, are outlined below: 

To Secure Breeding Habitat 

v To improve the reproductive potential of Green and Golden Bell Frogs at both 

locations, and hence improve population viability. 

To Increase Foraging, Shelter and Corridor Habitats 

v To improve the long-term survival prospects of the species at both locations 

through the creation of additional and enhanced areas of shelter, foraging and 

corridor habitat. While the Bell Frog populations at North Avoca and Davistown 

remain small and localised, they are extremely vulnerable to disruption and 

extinction. 

To Provide Greater Control over External Impacts 

v To reduce and control potential impacts as much as possible, while still permitting 

other land uses in the area. This is critical as the Bell Frog habitat areas are not 

isolated from urban areas and are subject to a range of impacts that are deleterious 

to the welfare of the Bell Frogs. 




To Continue to Undertake Monitoring and Adaptive Management 

v To establish a regular population monitoring regime at both North Avoca and 

Davistown. Without active management it is unlikely that either population of 

Green and Golden Bell Frogs will survive in the future. Management for a 

colonising species (such as Bell Frogs ) needs to both proactive and reactive. The 

objectives presented above deal with the proactive elements of the management of 

the frogs, the reactive component must be based on regular monitoring of the frog 

populations and consider emerging issues or threats as well as adopt an adaptive 

management technique whereby management practices can be progressively 

improved. 

7.2 Legislative Considerations and Compliance 

Before any Bell Frog conservation work can commence, several statutory requirements 

also need to be addressed. 

1. Potential impacts on other threatened species or endangered ecological 

communities 

The Bush Stone-curlew Burhinus grallarius, an endangered bird species, also occurs in 

the Gosford LGA. Sightings of this species have been made at a few locations around 

Davistown. The locations of these sightings are not included within the areas that are 

considered as potential habitat areas for Green and Golden Bell Frogs although both 

species have been recorded from close by sites at Davistown Road. For this reason, 

consideration must be given to the possible presence of the Bush Stone-curlew at some 

Bell Frog sites. 

A number of Endangered Ecological Communities (EEC) occur in the Gosford LGA and 

are relevant to this Plan of Management. These are Coastal Saltmarsh, Swamp Oak 

Forest, Freshwater Wetland and Swamp Sclerophyll on Coastal Floodplains. Table 3 

describes the corresponding vegetation communities that have been mapping in the areas. 

Saltmarsh and Swamp Oak Forest are present at Davistown while the other three 

communities occur at North Avoca. The proximity of Saltmarsh at the Pine Avenue Site 

at Davistown is one of the reasons that that site was given a low priority as a location for 

created habitat for Bell Frogs. The area available for habitat creation is small and would 

abut the saltmarsh. If habitat was constructed there, an impact assessment (Seven Part 

test) would need to be carried out. The other sites at Davistown are not adjacent to 

saltmarsh and will not impact this EEC. 




Table 3 

Vegetation Communities referred to in Plan of Management and likely to qualify as Endangered Ecological 

Communities) 

Map Unit Vegetation Community Name 

ENDANGERED ECOLOGICAL 

Bell 

COMMUNITY 

(2004) 

37ei Coastal Sand Swamp Forest 

Swamp Sclerophyll on Coastal Floodplains 

43ai Estuarine Paperbark Scrub-Forest 

40a Phragmites Rushland Freshwater Wetlands on Coastal Floodplains 

and Sydney Freshwater Wetlands 

47a Estuarine Saltmarsh/Grassland Coastal Saltmarsh 

40i Estuarine Swa mp Oak Forest Swamp Oak Floodplain Forest 

40b Estuarine Baumea Sedgeland 

The areas for Bell Frog habitat creation at Ilumba Avenue at Davistown and at Bareena 

Wetland at North Avoca are close to areas of vegetation that is likely to qualify as 

endangered ecological communities. However, the areas proposed for pond locations are 

not vegetated and it is not considered that there would be a significant impact on these 

areas as a result of the proposed ponds. Should a larger pond be created in the future, e.g. 

by creating another embankment across part of Avoca Lagoon, this forest type would be 

affected and an impact assessment (Seven Part test) would need to be carried out. 

2. Relevant Threatening Processes 

Two threatening process (listed under Schedule 3 of the NSW’s Threatened Species 

Conservation Act 1995) are relevant to the Plan of Management: Chytridiomycosis or 

Frog Chytrid Disease and predation by the introduced Gambusia or Plague Minnow. 

a) Chytridiomycosis 

Frog Chytrid Disease is a highly virulent and lethal disease of frogs. The pathogen is a 

micro-fungus, spores from which are easily transported in water, soil, mulch or compost, 

as well as by infected frogs. Habitat enhancement and bush regeneration techniques (see 

Appendix 4) proposed in this Plan do not require the importation of water, nor the use of 

imported mulch or compost. However, chytrid spores can also be transferred by frog 

workers and a Frog Hygiene Protocol (No. 6.) was developed by the Department of 

Environment and Conserva tion (DEC) that applies to field workers who may be handling 

frogs or working in frog habitats. The protocol is aimed at reducing the potential for the 




accidental spread of chytrid spores from an infected site to an uninfected site (see Section 

3 below). 

b) Predation by Gambusia 

Gambusia holbrooki is an exotic fish species that is known to prey on eggs and tadpoles 

of various native frogs including Green and Golden Bell Frogs (Pyke and White 1999). 

Any activity that increases the likelihood of Gambusia being introduced into a location is 

deemed to be threatening process. Gambusia are already present in Avoca Lagoon, 

throughout much of Davistown, and in many creeks and waterways on the Central Coast. 

The Plan of Management contains measures that will make it harder for Gambusia to 

invade Green and Golden Bell frog habitat and some measures are presented to eliminate 

Gambusia should they ever become established in core frog habitats. 

3. Safety and Hygiene Procedures 

The Frog Hygiene Protocol (DEC Protocol No. 6: Appendix 6) details various procedures 

to reduce the accidental spread of chytrid spores or other pathogens between aquatic 

habitats. The Plan of Management supports the need for regular monitoring of Bell Frogs 

at North Avoca and Davistown as well as supporting the measures presented in Protocol 

6. In brief, these measures include the sterilising of all frog monitoring equipment, boots 

or other items that may have been previously used at other aquatic sites. Frog holding 

bags are not to be re-used between sites and water, frogs or tadpoles are not to be moved 

between sites. This protocol is particularly relevant to all workers who are moving 

between frog sites. 

4. Handling or Interfering with Threatened Species or Endangered Ecological 

Communities 

Residents and contractors should be made aware that handling, harming or interfering 

with threatened species (such as Green and Golden Bell Frogs), and damaging or 

modifying Endangered Ecological Communities is in violation of the NSW Threatened 

Species Conservation Act 1995. Anyone wishing to work on threatened species will 

require a Scientific Licence from the Department of Environment and Conservation. In 

addition, Animal Ethics approvals will also be required from a relevant institution or 

government agency. 

Bush regeneration works that are undertaken in an endangered ecological community 

also require a S132C Scientific Licence issued under the Threatened Species 

Conservation Act 1995. 




5. Compliance 

The POM has also been prepared in accordance with the requirements for preparing plans 

of management for community lands and for lands identified as habitat for threatened 

species in Section 36 of the Local Government Act 1993. This includes identifying the 

category of lands identified as habitat for the species, objectives and performance targets 

for the plan with respect to the land, the means by which Council proposes to achieve the 

plan’s objectives and performance targets, and the manner in which Council proposes to 

assess its performance with respect to the plan’s objectives and performance targets. 

Accordingly, each land area is described in terms of its condition, the current and 

possible uses of the land, the nature of future permitted land uses, and the scale and 

intensity of likely future developments. In addition, any defined habitat type that applies 

to the land (e.g. natural area, wetland etc) is identified. 

The POM also conforms to the recommendations of the Draft Green and Golden Bell 

Frog Recovery Plan. The recommendations and proposals in the plan also heed the 

requirements of environmentally protected lands listed under Commonwealth, State or 

local government regulations. 

7.3 Recommendations for North Avoca Population 

In order to protect and enhance the population of the Green and Golden Bell Frog at 

North Avoca, the following actions are recommended: 

- Rezone the land in which the Bareena Wetland and nature 

strip occurs from 6a to 6b, as this would provide an 

increased basis for protection and conservation of Green 

and Golden Bell Frogs at North Avoca (Figure 11). In 

addition, this land is Crown Land (R53288) and it is 

recommended that Gosford Council request this land be 

transferred to Council-ownership and designated for public 

recreation and coastal protection. Parts of the embankment 

around the Bareena Wetland contain vegetation that may 

qualify as an Endangered Ecological Community (see 4.2). 

Bareena Wetland and the nature strip are on Crown Land. 

The area including Bareena Wetland has been included as a 

SEPP 14 wetlands. 




Figure 11 

Land Zones around the Bareena Wetland 

Legend for Figure 11 

Zone 

2(b) 

2(f) 

6(a) 

7(e) 

Description 

Residential 

Residential (Beach Frontage) 

Open Space (Recreation) 

Coastal Land Acquisition 




- Reduce the likelihood of establishment of Gambusia in the 

Bareena Wetland by: 

q 

q 

q 

Increasing the height of the wall between the 

lagoon and wetland, near its southern end, 

so that its height is roughly uniform 

throughout its length and water is no longer 

able to flow from the lagoon across the 

southern end of this wall. To minimize the 

siltation of the pond, additional soil and clay 

could be added to the outside wall and the 

height increased until to the desired level. 

Undertake regular fish surveys of Bareena 

Wetland to ensure that Gambusia is not 

present. This would require hand-netting 

sites across the area of the wetland. 

Eradicate Gambusia from the wetland if 

invasion by this fish species occurs. 

This might be achieved through draining the 

wetland during the next winter following 

invasion by Gambusia to allow Gambusia 

eradication through dessication. The 

lowering of the water level in the wetland 

would need to be carried out in conjunction 

with the opening of Avoca Lagoon. Once 

the water level in the wetland had fallen, the 

remainder could be mechanically removed 

using a water pump. If it is not possible to 

remove all of the water and allow the 

wetland to dry out completely, fish poisons 

may have to be used to kill the remaining 

Gambusia. The drying out of the wetland is 

the preferred method for eliminating 

Gambusia. The elimination of Gambusia 

from this wetland conforms with the 

directives of the Gambusia Threat 

Abatement Plan (Dept. of Environment and 

Conservation). The draining of the wetland 

should not adversely impact the plant 

communities or fauna reliant on this wetland 

as the Bareeena Wetland has a long history 

of being low or dry in response to the 




opening of Avoca Lagoon and natural 

variation in rainfall. 

- Decrease and control the average salinity in the wetland by: 

q 

Investigate the establishment of a 

stormwater system that diverts waste rainwater 

runoff into the wetland. Stormwater 

water that is not being used for other 

purposes can either be diverted from the 

roofs of nearby houses into the wetland or 

surface water can be diverted by a low bund 

into the wetland. If surface water is to be 

used, oil and grease traps will need to be 

installed between the wetland and the water 

source. If freshwater can be directed into the 

northern end of the wetland (via the refuge 

pond) a salinity gradient will be created 

across the wetland with less saline water at 

the northern end and more saline water 

towards the southern end. 

The high salinity of the Bareena Wetland is 

one of the main reasons that Bell Frogs are 

unable to reliably breed at this site; calling 

Bell Frogs are often heard around the 

Bareena Wetland but the prevailing saline 

conditions often results in the death of 

tadpoles or the failure of eggs to hatch. 

q 

Maintaining, through this mechanism, 

salinity within the wetland that is in the 

range 2-6 ppt as much as possible during 

spring and summer. 

- Integrate draining of lagoon with management of the Green 

and Golden Bell Frog population through adoption of 

protocols developed by Gosford City Council: 

q 

Protocols need to be established to 

determine when Avoca Lagoon should be 

drained. The conditions whereby opening 

the lagoon should occur need to be stated, as 

must the conditions when the lagoon should 

not be opened (e.g. when there are tadpoles 




in Bareena Wetland). In the past, the 

decision to open the lagoon has been based 

on the current water levels in the lagoon and 

the advent of further rain. This system can 

no longer be used as it does not take into 

account the impact of lowering water levels 

and increased salinity in the Bareena 

Wetland. The protocols may identify 

seasons when opening the lagoon should not 

occur; similarly, the protocols may allow 

pre-emptive lowering of the lagoon (e.g. 

during each winter). The protocols need to 

be prepared by Gosford City Council in 

collaboration with all stakeholders and 

should contain: 

q 

q 

A list of contact names and numbers of all 

relevant personnel and stakeholders. This 

list will include Council Staff as well as 

members of the public. 

A person (or group of people) from the 

Recreation and Natural Resources Unit of 

Gosford City Council must be assigned 

responsibility for the management and coordination 

of the response to the opening of 

the lagoon. 

The procedures for the opening of the 

lagoon need to be detailed, along with daily 

reports to the Recreation and Natural 

Resources Unit of Council following the 

opening of the lagoon. An inspection of the 

Bareena Wetland will need to be carried out 

and tadpoles/ frogs recovered if need be. 

The personnel and timing of the inspection 

(and frog rescue) needs to be predetermined. 

The licences and qualifications 

of all involved in the frog rescue need to be 

established along with a suitable timeframe 

for these events. 

All parties involved in the opening of the 

lagoon must be able to easily contact each 

other. 




During any period when the opening of the 

lagoon is being considered, the management 

group (or person) must be informed as soon 

as possible 

Upon advice that the opening of the lagoon 

is to proceed, the management group (or 

person) must arrange a tadpole survey of the 

Bareena Wetland; water parameters also 

need to be measured. The surveys need to be 

carried out by a person competent in 

identifying tadpoles. This person will also 

need to assess the presence and density of 

Bell Frog tadpoles, carry out the water 

parameter measurements (especially 

salinity) and assess the immediate and future 

(i.e. in 3 months) suitability of frog breeding 

habitat. Tadpoles may need to be relocated 

to the supplementary frog pond at Bareena 

(if it contains freshwater). The pond may 

need to be filled with freshwater if a water 

supply (such as a bore) is present. If the 

pond is likely to remain dry, tadpoles may 

need to be held temporarily at the Australian 

Reptile Park for later re-release into the 

Bareena Wetland. 

If tadpoles are apparently absent from the 

Bareena Wetland, but water conditions are 

such that suitable breeding conditions exist, 

or are likely to exist for the next three 

months (i.e. salinity below 6 ppt at the start 

of the breeding season), then the 

management group (or person) should strive 

to have the opening of the lagoon deferred 

until after breeding and tadpole development 

has taken place. 

Within two weeks after the opening of the 

lagoon, the management group (or person) 

will need to prepare a report for Council on 

the impact of the opening on the Bareena 

Wetland and the local Bell Frog population. 




q 

The nature strip around Bareena Wetland 

needs to be managed and again Gosford City 

Council will need to develop protocols to 

ensure that the management of this area is 

not in conflict with this Plan of 

Management. The protocols will include 

details such as where and when mowing will 

occur, where and when herbicides can be 

used, information sharing between the 

Recreation and Natural Resources Unit, and 

the Section that manages Parks and Gardens 

to ensure that all staff understand the issues. 

Some induction and training may be 

required in frog identification and handling, 

and a policy regarding the treatment of frogs 

found during mowing. Finally, consideration 

will have to be given to any licensing issues 

or government approvals that may be 

relevant (e.g. bush regeneration work in 

Swamp Oak Forest may require an impact 

assessment before any work can take place 

there). 

- Manage the vegetation in the wetland area as follows: 

q 

q 

Carry out additional planting of Lomandra 

or other similar species in clumps along the 

wall in order to increase the availability of 

thick low vegetation in this area (as per the 

Bush Regeneration Plan, Appendix 5). 

Require that, before being approved, all 

proposals to modify the vegetation in this 

area be presented in writing and evaluated 

by someone with appropriate expertise in 

terms of habitat requirements of the Green 

and Golden Bell Frog (as per the Bush 

Regeneration Plan, Appendix 5). 

- Manage the vegetation of the mown area (nature strip) as 

follows: 

q 

Maximize the area that is left unmown by 

establishing and marking areas in which 

mowing will not occur (see Bush 

Regeneration Plan, Appendix 5). 




q 

q 

Increase the availability of thick low 

vegetation through increased planting, in 

clumps, of suitable species such as 

Lomandra (see Bush Regeneration Plan, 

Appendix 5). 

Avoid use of herbicides, pesticides, fertilizer 

and other chemicals in the wetland and in 

areas that drain into the wetland (see notes 

in Appendix 5). 

- Encourage local land-owners and residents to contribute to 

the protection and recovery of the Green and Golden Bell 

Frog in the following ways: 

q 

q 

q 

q 

q 

q 

q 

q 

Include areas of thick low vegetation (such 

as Lomandra and Crinum ) within garden 

plantings; 

Establish and maintain a garden pond, 

preferably without fish; 

Use other means (as identified in surveys 

described below) to make their yards ‘frog 

friendly’ for the Green and Golden Bell 

Frog; 

Minimize the use of pesticides and other 

chemicals and prevent their discha rge into 

urban water runoff. “Frog-friendly” 

formulations are to be used; 

Collect and remove dog droppings from 

nature strip 

Increased community awareness of frogs on 

roads at night; 

Participate in the frog surveys; 

Report opportunistic observations of frogs. 

Development of supplemental pond habitat for the Green and Golden Bell Frog near the 

Bareena Wetland: 

The development of supplementary pond habitat at North 

Avoca is considered an important adjunct to habitat 

enhancements for Green and Golden Bell Frogs Where 

possible enhancement of habitat has been suggested but the 

available space for pond creation is limited. The existing 

frog habitat in the wetland is dynamic and has sustained 




Bell Frogs at a site while the species has perished rapidly 

from surrounding areas. To markedly interfere with 

functional habitat when the population is apparently so 

fragile would be extremely hazardous, and in our opinion, 

not justified. New ponds sites need to be created but not at 

the expense of existing habitat. In order to satisfy the need 

for new or additional breeding sites, artificial ponds are 

proposed in areas where they do not replace existing frog 

habitat. 

Two types of supplementary ponds are considered to be 

needed at North Avoca: 

q 

q 

Provision of a more-secure breeding pond 

in the proximity of the Bareena Wetland; 

Provision of a refuge pond which could 

receive any tadpoles that are rescued from 

the wetland when water levels there become 

very low (e.g. when the lagoon is drained – 

Consterdine 1999a). 

A long-term goal is the creation of significant additional 

breeding habitat for the Green and Golden Bell Frog 

adjacent to the existing Bareena Wetland. Ideally, this 

would be achieved through the development of a bund wall 

(additional to the one already there) to separate the lagoon 

from an additional area of potentially freshwater wetland 

(in the same manner as happened when the original wall 

was created). A wall could, for example, be developed from 

near the southern end of the existing wall, around the 

western edge of the shallow and partly vegetated adjacent 

part of the lagoon until dry land is reached (see Fig. 13). 

This would create a reasonably large area of additional 

wetland habitat similar to the existing Bareena Wetland that 

should act as breeding habitat for the frog. Because the two 

wetland areas would be adjacent to one another, frogs 

would easily be able to move between them. It is not 

possible to develop effective breeding habitat for the Green 

and Golden Bell Frog elsewhere because the only land area 

that is sunny and close to Bareena Wetland is too small to 

accommodate more than a small pond. The difficulty with 

locating a large pond in this area is that it will intrude into 

existing SEPP 14 wetland and could also impinge on 

potential endangered ecological communities. An 

Environmental Impact Statement (EIS) would be required 




for these earthworks. In addition, there may some some 

dissatisfaction by local residents if as pond is created at this 

site. 

We also recommend that, within the area between the 

northern end of Bareena Wetland and nearby residential 

blocks (i.e. in the nature strip), a relatively small pond (i.e. 

~5m diameter) be developed to act primarily as a refuge for 

tadpoles that are rescued from the wetland when the lagoon 

is opened to the ocean. If built according to the 

specifications provided (see Appendix 1), this pond could 

potentially make a small contribution to the available 

breeding habitat. This pond could receive input of 

freshwater through diversion of storm water runoff from 

nearby urban area or through a bore and pump. A low 

diversion bund could be created across the nature strip that 

would divert surface water into the pond, which in turn 

would overflow into the wetland. Investigations should be 

carried out to determine the best means of directing 

additional freshwater into the refuge ponds (and the 

wetland). A fence around this pond would protect the frogs 

from disturbance and provide for child safety. 

- Areas of frog habitat need to be maintained by routine 

weed control and bush rehabilitation methods (as described 


- Frog habitat areas should also be signposted so that 

their significance and purpose is apparent to passers-by. 

- Garden ponds may provide refuge for frogs that make their 

own way to them but are not seen as refuge sites for 

tadpoles. If tadpoles were translocated to such ponds and 

subsequently metamorphosed into frogs, they would not 

know the location of the breeding area, nor how to get 

there. A small percentage might find the breeding area by 

chance but almost all would be lost from the breeding 

population. 

- Monitor the population of the Green and Golden Bell Frog 

and its habitat. 




Monitoring the Green and Golden Bell Frog at 

North Avoca should be carried out according to the 

general monitoring strategy, as described below 

(see Appendix 4). It should focus on the Bareena 

Wetland and the supplemental pond when built. 

Monitoring should be carried out by a community 

group comprising interested residents and 

conservation-minded people, under the guidance 

and supervision of staff from the Australian 

Museum, Australian Reptile Park or Gosford City 

Council. A licence issued by the Department of the 

Environment and Conservation will be required by 

those who will be responsible for any handling, or 

studying the frogs, and all procedures relating to the 

management of Green and Golden Bell Frogs must 

comply with the NSW Threatened Species 

Conservation Act 1995. Volunteers who assist with 

monitoring under supervision will not require their 

own licence, but would require a licence to carry 

out such activities unsupervised. 

- Establish a captive-breeding colony of Green and Golden 

Bell Frogs derived from the Bareena Wetlands at the 

Australian Reptile Park or other suitable venue. 

The captive-breeding colony will be a safe-guard in 

the event that disease (such as chytrid) or mishap 

results in the extinction or decline of the Bell Frog 

population in the Bareena Wetland. 

Progeny from the captive-breeding colony may be 

used to restock the Bareena Wetland (if necessary) 

or to establish new Bell Frog sites nearby (e.g. Woy 

Woy, Umina, Pearl Beach). However, to minimise 

the likelihood of diseased animals being released 

into the wild, samples of them will have to be 

screened for pathogens before any release occurs. 

Approval would be required from the Department 

of Environment and Conservation before tadpoles 

could be translocated. 




7.4 Recommendations for Davistown Population 

Overall strategy 

In order to protect and enhance the population of the Green and Golden Bell Frog at 

Davistown, the following actions are recommended: 

- Rezone the Ilumba, Romford and Magnolia Wetlands that 

contain Green and Golden Bell Frog habitat from 6a to 6b 

(Figure 12). These areas include frog dispersal corridors 

such as drainage lines and floodways. These wetlands also 

contain important vegetation and ecosystem types that have 

been mapped and included in SEPP 14 wetlands (these 

include areas of salt marsh areas, Swamp Oak Forest and 

freshwater swamps). Swamp Oak Forest is considered an 

Endangered Ecological Community under the Threatened 

Species Conservation Act 1995. Most of the land in these 

wetlands is owned by Gosford City Council (Table 4) 




Figure 12 

Land Zones at East Davistown 

Legend for Figure 12 

Zone 

2(a) 

3(c) 

5(c) 

6(a) 

7(a) 

Description 

Residential 

Business (Central) 

Special Uses 

Open Space (Recreation) 

Conservation and Scenic Protection 




Table 4 

Land Ownership and Planning Details of Wetlands at Davistown used by Bell Frog as 

Habitat Areas 

Location 

Morton 

Crescent 

Dilgara 

Avenue 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Lot 

No. or 

DP 

Lot 28 

DP 

22514 

Lot 

29/30 

DP 

14359 

Lot 53 

DP 

6014 

Lot 802 

DP 

544701 

Lot 1 

DP 

580716 

Lot 2 

DP 

580716 

Lot 76 

DP 

8014 

Owner 

ship 

Private 

Community 

or 

Operational 

Land 

Not 

applicable 

Current 

Zoning 

Proposed 

rezoning 

Proposed 

Classif 

ication 

2a 7a - 

Council Community 2a 6b - 

Private 

Not 

applicable 

2a 7a - 

Natural 

Area or 


Natural 


Natural 

Target 

Natural 


Natural 

Council Operational 2a 6b Communi 

ty Wetland Wetland 







Notes 

GGBF 

corridor 

habitat 

GGBF 

corridor 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Lot 75 

DP 

8014 

Lot 74 

DP 

6014 

Lot 73 

DP 

6014 

Lot 72 

DP 

6014 

Lot 9 

DP 

6014 

Lot 10 

DP 

6014 

Lot 11 

DP 

6014 

Private Community 2a 6b - 




Private Community 2a 6b - 

Natural 




Natural 

Natural 




Natural 






GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

GGBF 

Shelter 

habitat 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Kincumb 

er 

Crescent 

Lot 63 

DP 

812108 

Lots 

45,46,4 

7 

DP 

6014 

Lots 

22-33 

DP 

12702 

Council Community 2a 6b - Wetland Wetland GGBF 

Shelter 

habitat 

Council Community 6a - - GGBF 

Shelter 

habitat 

Council Community 6a 6b - GGBF 

Shelter 

habitat 




Magnoli 

a Avenue 

Magnoli 

a Avenue 

Magnoli 

a Avenue 

Ilumba 

Avenue 

Lot 102 

(part 1) 

DP 

5820 

Lot 105 

(part) 

DP 

938078 

Lot 015 

(part) 

DP 

936248 

Lots 

104 & 

105 

(part) 

Lot 102 

& 103 

DP 

5820 

Lot 6 

DP 

12702 


Shelter 

habitat 


Shelter 

habitat 


Shelter 

habitat 


ty 

GGBF 

Corridor 

Habitat 

It is also recommended that the above Lots currently zoned 2a that are Council owned be 

rezoned to 6b Open Space (Flora and Fauna Preservation). Also Council owned lands 

that are currently classified as Operational need to be reclassified to Community lands. 

Private owned lands that are currently zoned 2a are proposed to be rezoned to 

7a(Conservation) because of their environmental significance. 

Gosford City Council, in the context of considering development applications, must, 

under the Environmental Protection and Assessment Act 1979, evaluate the impacts of 

any proposed human development on the wetland habitat discussed above. 

- Human activities within the wetland areas could affect 

the habitat of the Green and Golden Bell Frog either 

directly, through loss of wetland habitat, or indirectly, 

through changes to water drainage patterns. These activities 

should be actively discouraged or prevented. In particular, 

residents need to be made aware that they should not be 

catching or handling Bell Frogs, as this is in contravention 

of the Threatened Species Conservation Act 1995, and may 

also breach the Frog Hygiene Protocol No 6 (DEC). Only 

licensed individuals or those acting under a licence are 

legally able to handle endangered or other frog species. 

Routine surveys of Bell Frog habitat areas should be 

carried out to create a better understanding of changes to 

the population through time and in response to newlycreated 

habitats (see Appendix 4). Monitoring should be 

carried out by a community group comprising interested 

residents and conservation-minded people, under the 

guidance of staff from the Australian Museum, Australian 

Reptile Park and Gosford City Council. Monitoring the 




Green and Golden Bell Frog at Davistown should be 

carried out according to the general monitoring strategy, as 

described below. It should focus on the wetland areas 

between Magnolia Avenue and Kincumber Avenue near 

Romford Close and on additional pond breeding habitat 

when built. 

- Development of more secure breeding habitat for the Green 

and Golden Bell Frog at suitable locations within 

Davistown. A number of potentially suitable locations have 

already been identified. These are discussed below. Other 

such locations may be identified in future. 

- Areas of frog habitat need to be maintained by routine 

weed control and bush rehabilitation methods (as described 


- Encourage local land-owners and residents to contribute to 

the protection and recovery of the Green and Golden Bell 

Frog in the following ways: 

q 

q 

q 

q 

q 

q 

q 

Include areas of thick low vegetation within 

garden plantings; 

Establish and maintain a garden pond, 

preferably without fish; 

Minimize the introduction of pesticides and 

other chemicals into urban water runoff; 

Avoid hitting frogs while driving along the 

roads; 

Participate in the frog surveys; 

Report other opportunistic observations of 

frogs 

Avoid touching or handling Bell Frogs 

- Establish a captive-breeding colony of Green and Golden 

Bell Frogs derived from the Davistown at the Australian 

Reptile Park or other suitable venue. 

The captive-breeding colony will be a safe-guard in 

the event that there is extinction or decline of the 

Bell Frog population at Davistown. 

Progeny from the captive-breeding colony may be 

used (if free of disease) to restock sites at 

Davistown (if necessary) or to establish new Bell 




Habitat creation 

Frog sites nearby (e.g. Woy Woy, Umina, Pearl 

Beach). Permission from DEC will be required for 

any reintroductions of Bell Frogs. 

The following three sites have been identified, after various potential sites were 

investigated, as having the greatest potential for the creation of breeding ponds for the 

Green and Golden Bell Frog (see Figure 13): 

- Illumba Easement: council land behind houses along east 

side of Ilumba Avenue (i.e. between houses and Romford 

Wetland) currently maintained as a grassed strip. 

- Pine Avenue Reserve: reserve at corner of Pine Avenue and 

Lillipilli Street 

- Malinya Site: Area along and adjacent to a trail on the 

south side of Malinya Road. 

These three sites were selected as they are close to existing Bell Frog movement areas or 

existing habitat, can be readily developed or require minimal habitat change and are 

relatively free of the risk of natural invasion by Gambusia. 

These sites all have some desirable features in terms o f possible development of breeding 

habitat for the Green and Golden Bell Frog. Each site provides sufficient space for at 

least one pond that is constructed according to the desired specifications (see Appendix 

1). Pond or ponds would receive little or no shade, and surrounding vegetation could be 

maintained to allow direct sunlight onto the ponds. A source of freshwater could be 

established by diverting rainwater runoff from the garage and sheds that back onto the 

area into the pond. Invasion by Gambusia should not occur and the pond should be 

drainable to eradicate fish should they ever become established in the pond. There is 

adjacent habitat suitable for foraging and sheltering by Bell Frogs. 

Of the three sites, the Ilumba Easement Site appears to offer the most potential in terms 

of breeding habitat for the Green and Golden Bell Frog. Most importantly, this site is 

very close to locations where frogs of this species have recently been observed and is 

close to the area where breeding by the species has probably occurred. There is a cleared, 

rectangular land area, about 20 metres wide and 150 metres long, in which one or more 

ponds could be built without major earthworks. This area is alongside mapped SEPP 14 

wetlands (Figure 16) and could be developed as frog habitat without disturbing the 

Swamp Oak Forest nearby. More than one pond is advocated as this makes it possible to 

vary water levels and create artificial disturbance regimes in one pond without negating 

ponds that are more stable. The ponds could be fed by water that falls as rain on the roofs 

of the nearby houses. Foraging and shelter habitat can also be developed (see Appendix 1 

for details). 




Figure 13 

Bell Frog Habitat Enhancement Areas at Davistown 

Because of the presence of acid-sulphate soils immediately beneath the topsoil, the ponds 

at this site cannot be excavated into the ground, as would be most desirable (see 

Appendix 1). Instead the ponds will need to be above-ground with a pre-fabricated shell 

that are only partially imbedded into the ground. A safety fence would be required around 

the pond or a thick metal grill placed across the top of the ponds. 

The Pine Avenue Site has less potential than the Ilumba Easement Site as there is less 

available space for habitat creation and areas that could be developed are constrained by 

surrounding areas of saltmarsh vegetation (also SEPP 14). It would be possible to 

construct a small pond on the site and supply that pond with rainwater runoff from the 

nearby houses. The Pine Avenue has the distinct disadvantage of being close to a major 

thoroughfare and road-killed frogs are likely to occur. 

The Malinya Road Site is reasonably large and has enough space for a number of ponds 

to be situated there. Construction of the ponds would require considerable earthworks in 

the area. Bell Frogs are not known from the Malinya Road Site and this may be a site for 




future consideration as a translocation site for Bell Frogs bred elsewhere at Davistown. 

The only apparent source of water for ponds at this site is rain that falls directly on the 

site. Additional earthworks would therefore be necessary in order to ensure that surface 

water is directed into the ponds. Investigations are required to determine methods of 

diverting more freshwater into the wetlands and frog ponds. 

Other sites were considered and were dismissed because of issues relating to land tenure, 

lack of habitat potential or major conflicts in land use. 

Bell Frog habitat areas should be appropriately signposted so that their significance is 

apparent to passers-by. Initially sign posts are only required near the Ilumba Wetland 

Frog breeding ponds. As the Davistown Bell Frog population recovers, additional signs 

may be required in the Magnolia and Romford Wetlands. 

The unsealed drains in Magnolia Avenue have been sued as breeding sites by Bell Frogs. 

It is recommended that these drains not be sealed and that water sensitive urban design 

alternatives be used instead of concrete curb and gutters along the streets near the 

wetlands. The existing drains can be vegetated to improve their habitat value so that they 

can also provide foraging area sand safe movement corridors through the urban parts of 

Davistown. 

7.5 Summary of Recommendations 

The recommendations that have been discussed in this report have different priority of 

action, costs and management considerations; these have been summarised in Table 5 

below; the recommendations have been ranked according to how much they are likely to 

benefit the Green and Golden Bell Frog populations at either North Avoca or Davistown. 

Priority 

No 

Action 

1 Install translocation pond 

and water supply at North 

Avoca 

Table 5 

Summary of Recommendations 

Reference 

in Plan 

Estimated 

Material 

Costs 

Funding 

7.3 $15,000 GGBF 

Imp lementatio 

n Budget* 

Who is 

responsible? 

GCC 

2 Install artificial ponds at 

Ilumba Site at Davistown 7.4 $20,000 WWF Grant** GCC 

3 Rezone Bareena Wetland 

and Nature Strip from 6a 

to 6b and request transfer 

from Crown Lands to 

GCC. 

4 Rezone Ilumba, Ro mford 

and Magnolia wetland 

7.3 0 - GCC 




and Magnolia wetland 

and associated areas at 

Davistown from 2a to 6b 7.4 0 - GCC 

5 Investigate opportunities 

to create system for the 

- 

diversion of clean surface 7.4 $25,000 

GCC 

runoff into Bareena 


6 Investigate opportunities 

to create system for the 

-, 

diversion of clean 

GCC 

surface runoff into 

Ilumba and Magnolia 

Wetlands 

7.5 $50,000 

7 Develop routine 

monitoring regimes for 

both North Avoca and 

Davistown 7.3, 7.4 $5,000- 10,000 

per annum 

8 Establish quick response 

protocol in event of 

lowering of Avoca 

Lagoon, including 

tadpole survey (and 

translocation) at Bareena 


9 Demarcation of “no 

mow” areas at North 

Avoca 

10 Closure of western 

walking track and signage 

for Bareena Wetland Appendix 5 

7.3 

11 Weed control, bush 

rehabilitation works and 

replanting of shelter 

habitat vegetation at 

North Avoca 

12 Weed control, bush 

rehabilitation works at 

Ilumba, Magnolia and 

Romford Wetlands 

13 Planting of shelter habitat 

plants and rock/log piles 

GCC 

Recurrent 

budget 

GCC 

Community 

Groups 

DEC 

Aust Museum 

Aust Reptile 

Park 

7.3 0 - GCC 

Appendix 5 

7.3 $ 2,000 

$1,000 

Appendix 5 $ 15,000 - 

20,000 

7.3 

Appendix 5 

Ilumba pond site 7.4 $ 1,000 

14 Establish captive 

breeding colonies of Bell 

Frogs from North Avoca 

and Davistown 

15 Develop additional Bell 

frog breeding pond near 


7.3 

7.4 

GGBF 

Implementatio 

n Budget 

GGBF 

Implementatio 

n Budget 

GGBF 

Implementatio 

n Budget 

GCC 

Recurrent 

budget 

WWF Grant 

funding 

- - 

7.3 

Appendix 1 $100,000 NHT 

GCC 

GCC 

GCC 

GCC 

GCC 

Aust Reptile 

Park 

GCC 

DEC 




16 Develop additional Bell 

frog breeding ponds at 

Davistown eg. Malinya 

Ave or Pine Ave) 7.4 $75,000 NHT 

17 Maintenance of Bareena 

Wetland and Nature Strip Appendix 5 $ 10,000 p.a 

7.3 

18 Maintenance of Ilumba 

Frog Pond Site and other 

Bell Frog habitats 7.4 $5,000 p.a. 

19 Encourage the 

development of “back 

yard” Bell Frog ponds at 

North Avoca and 

Davistown 

20 Raise height of southern 

berm at Bareena Wetland 

21 Extend search areas to 

locate Bell Frog habitats 

used at Avoca Lagoon 

and Davistown 

22 Develop Gambusia 

control plan for Bareena 


23 Develop greater 

community awareness of 

Bell Frogs and 

conservation measures at 

North Avoca and 

Davistown 

7.3 

7.4 

Recreation and 

NR 

Maintenance 

Budget 

(recurrent ) 

Recreation and 

NR 

Maintenance 

Budget 

(recurrent ) 

$ 10,000 NHT 

Aust Museum 

GCC 

DEC 

Aust Museum 

GCC 

GCC 

GCC 

Local 

Community 

Groups 

7.3 $10,000 NHT GCC 

7.3 

7.4 

$5,000 NHT 

(for staff time) 

GCC 

Local 

Community 

Groups 

Aust Museum 

Aust Reptile 

Park 

7.3 $2,500 NHT GCC 

7.2 

7.3 

7.4 

$ 2,000 

GGBF 

Implementatio 

n Budget 

GCC 

Local 

Community 

Groups 

Aust Museum 

Aust Reptile 

Park 

*Note that there is already a budget for the Implementation of the Green and Golden Bell 

Frog Plan of Management for $30,000. 

**Also some grant funding for the construction of Bell Frog Habitat at Davistown and 

community monitoring for $18,000. 

8.0 Further Investigation 

Further investigation would enhance the likelihood of survival for both the North Avoca 

and Davistown populations of the Green and Golden Bell Frog. Recommendations for 

such investigation, along with descriptions of how it would benefit the frog, are presented 

below. 





Garden surveys 

It is recommended that surveys be undertaken of residential 

gardens to investigate their use by Bell Frogs and to assess the 

extent of available frog habitat: 

q 

q 

q 

q 

q 

q 

q 

Surveys should include as many as possible of the 

residential blocks along the streets near Bareena Wetland 

(i.e. Bareena Avenue, Lake Street, Ocean Street, Tramway 

Road) 

Surveys should target between 50 and 100 residential 

blocks 

Each block should be surveyed at night on two occasions 

during the period October-March. 

Residents should be encouraged to participate in these 

surveys and to contribute additional opportunistic 

observations where possible 

Each block should be surveyed once to assess the nature 

and extent of available frog habitat 

The presence of dogs or cats should be recorded 

Nature and extent of watering of garden areas should be 

recorded 

Such surveys should result in the following: 

q 

q 

q 

q 

Determination of the factors that encourage/ discourage use 

of urban gardens by Green and Golden Bell Frogs 

Recommendations regarding how land owners can make 

their gardens more ‘frog friendly’ for Green and Golden 

Bell Frogs 

Strategies for improving the survival, growth and 

development of Green and Golden Bell Frogs within the 

urban component of their overall habitat 

A better indication of the extent and location of the Green 

and Golden Bell Frog population and habitat in North 

Avoca 

Any such results could also be applied at Davistown. 

8.2 Davistown 




Wetland surveys 

It is recommended that surveys of the Ilumba, Magnolia and 

Romford wetland areas be carried out as follows: 

q 

q 

q 

A number of specific locations (i.e. 10-15) should be 

chosen within these wetland areas in order to encompass 

the likely range in terms of potential places where the 

Green and Golden Bell Frog might breed. Some of these 

sites could occur on private land and permission would 

need to be sought for these surveys to be carried out. 

Each of these locations should be sampled for water 

characteristics (including salinity and water temperature) at 

regular intervals of 6-7 weeks during the period October- 

March over at least two years 

Each of these locations should be surveyed, at the same 

times, for identity and abundance of tadpoles and fish 

Such surveys should result in the following: 

q 

q 

q 

Determination of the spatial and temporal patterns of 

salinity and other habitat parameters within these areas and 

how these affect breeding by the Green and Golden Bell 

Frog. 

Assessment of the relative value of different parts of these 

wetlands for breeding by the Green and Golden Bell Frog 

and hence recommendations in terms of the relative 

conservation value of each part of the wetlands and the 

habitat present. 

It would thus be possible to determine which areas warrant 

protection for this species and which habitat properties (e.g. 

low salinity) of these areas warrant protection and/or 

enhancement. 

Hydrological investigation 

It is recommended that a more detailed hydrological investigation 

of the Ilumba, Magnolia and Romford wetland areas and their 

water catchments be carried out. To date, hydrological surveys 

have been limited to potential breeding sites. The aims of the 

extended surveys would be to: 

q 

Determine what factors control the patterns of salinity and 

Gambusia within these wetland areas and how these factors 

operate. 




q 

q 

q 

Identify and evaluate alternative strategies by which 

patterns of water flow might be maintained or modified for 

the benefit of the Green and Golden Bell Frog through 

protecting or increasing conditions of suitably low salinity 

and controlling or reducing the distribution and/or 

abundance of Gambusia. 

Develop a recommended strategy for maintaining and/or 

enhancing the breeding habitat for the Green and Golden 

Bell Frog within these wetland areas. 

Evaluate potential artificial methods by which the average 

salinity in these wetland areas could be decreased (i.e. 

water conditions with suitably low salinity for frog 

breeding could be increased), while controlling or reducing 

the distribution and/or abundance of Gambusia. 

Garden surveys 

There are a number of such methods that could be 

considered. Rainfall runoff (e.g. from the roofs of houses) 

that is presently channeled into the bay might be redirected 

into the wetland areas. Tidal influx of saltwater into the 

wetland areas might be reduced through appropriate 

barriers. Elimination of water connections between some 

areas might reduce the ability of Gambusia to move 

between different areas and hence reduce its overall 

distribution. 

Any measures considered that might alter the salinity of a 

wetland areas needs also to consider whether these changes 

are likely to also adversely impact surrounding ecological 

communities, such as Coastal Saltmarsh. 

It is recommended that, once the breeding habitat of the Green and 

Golden Bell Frog at Davistown has been properly identified 

(through surveys described above), garden surveys be carried out 

along nearby streets in similar fashion to the surveys recommended 

above for North Avoca. 

9.0 Recommendations and Priorities 

Table 5 contains a summary of the recommendations. These recommendations appear 

throughout the Plan of Management. By compiling the recommendations in one place 

they can be used as a checklist of tasks to be completed. In addition, the 

recommendations have been prioritized according to whether there is a need for 




immediate action, medium term response or long-term action required. The section of the 

report where the recommendations appear in full are presented in brackets at the end of 

each point. 

9.1 North Avoca: 

Table 5 summarises the recommendations arising from the bulk of this report. However, 

additional recommendations arises as a consequence of the Bush Regeneration Plan 

(Appendix 5). The recommendations below combines both sets of recommendations into 

a list of actions. Recommendation numbers used in Table 5 are listed in brackets while 

those arising from the Bush Regeneration Plan are cites as BRP. 

Immediate Action 

1. Rezone Bareena Wetland from 6a to 6b (3). 

2. Create single refuge pond at northern end of wetland (1). Enclose in security fence. 

Install bore and pump as water supply. 

3. Investigate means to divert additional stormwater run-off into new pond and Bareena 

Wetland.(5). 

4. Enhance foraging and shelter sites around new pond and existing wetland (11, BRP). 

Medium Term Action 

5. Demarcate mowed areas of the nature strips so that frog habitat areas are excluded 

from mowing and other land clearing activities (9, BRP). 

6.Close western walking track (10). 

7. Remove weeds from within frog habitat areas, supplementary planting of ground cover 

vegetation as required (14, BRP). 

7. Create additional shelter habitat through planting or use of rock piles (14). 

8. Signage to indicate the significance of the Bareena Wetland and how to avoid 

damaging it e.g. by dumping garden wastes.(10, BRP.). 

9. Increase height of southern berm (20). 

10. Create an administrative structure so that any decision to change the water level in 

Avoca Lagoon must be considered in terms of its impact on the Green and Golden Bell 

Frogs (8). 

Long-term Actions 

11. Manage the breeding pond so that it continues to provide a secure breeding site for 

the frogs (16). 

12 Carry out regular monitoring of the Bell Fog populations, and encourage local 

residents participation in this. (7). The survey area should include residential areas where 

Bell Frogs have been recorded in the past and potential habitats (21). 

13. Establish a captive-breeding colony of Bell Frogs from Bareena Wetland that serve as 

a safe-guard in the event of mishap to this population and which could also be used to 

restock this site or newly-developed alternate sites (13). 

14. Encourage nearby residents to develop Bell Frog habitat in their backyards (19,23) 




15. Develop greater community involvement in the monitoring and management of Bell 

Frogs at Davistown (23). 

16. Greater community and Council awareness of the Frog Hygiene Protocol and the 

legal requirements the affect the handling and treatment of endangered frogs (23). 

9.2 Davistown 

Immediate Action 

1. Develop the Ilumba Easement Site to become additional breeding habitat area for Bell 

Frogs at Davistown. (2, BRP). 

2. The Ilumba Easement Site requires secure breeding habitat. Install one or more aboveground 

prefabricate ponds that have access to mains water as well as roof runoff from 

nearby buildings. Develop shelter and foraging habitat nearby. (2). 

3. Rezone Ilumba Easement Site, Magnolia Wetland and Romford Wetland from 6a to 6b 

(4). 

4. Investigate means to divert clean stormwater runoff into Romford, Magnolia and 

Ilumba Wetlands (6). 

5. If these areas cannot be rezoned, any development in these areas or nearby must be 

considered in terms of their impacts on Green and Golden Bell Frogs. 

Medium Term Action 

6. Create additional shelter habitat through planting tussock vegetation or use of rock 

piles, log or sleepers in the Ilumba Easement Site (12, BRP). 

7. Develop additional breeding habitat at Davistown (16) 

8. Signage to indicate the significance of the Ilumba Wetland frog habitat area and how to 

avoid damaging it e.g. by dumping garden wastes (18,23). 

9. Encourage local residents to participate in the surveys and to assist with managing the 

frog habitat areas (23). 

10. Extend areas of surveys to include residences not previously included in surveys 

(7,21) 10. Monitoring surveys should also include water characteristics, fish surveys and 

habitat assessments (7). 

Long-term Actions 

11. Continue monitoring of the Bell Frog Population and new frog habitat areas (7, 21). 

12. Develop a management process whereby all issues that effect Bareena Wetland, 

Ilumba Easement Site, Magnolia Wetland and Romford Wetland are considered in terms 

of their impacts on Green and Golden Bell Frogs (18). 

13. Develop other Bell Frog habitat areas (e.g. Malinya and Pine Avenue Sites) (16, 

BRP). 

14. Investigate methods by which water flow or salinity can be regulated in the wetlands 

to the benefit of Bell Frogs (6,15). 

15. Encourage nearby residents to develop Bell Frog habitat in their backyards (19) 




16. Establish a captive-breeding colony of Bell Frogs from Davistown that serve as a 

safe-guard in the event of mishap to this population and which could also be used to 

restock this site or newly-developed alternate sites (13). 

17. Develop greater community involvement in the monitoring and management of Bell 

Frogs at Davistown. 

18. Ensure or develop greater community and Council awareness and implementation of 

the Frog Hygiene Protocol and the legal requirements the affect the handling and 

treatment of endangered frogs. 

10.0 References 

Bell Stephen (2004) The natural vegetation of the Gosford Local Government Area, 

Central Coast, New South Wales Technical Report, Community Profiles and Mapping 

prepared for Gosford City Council. 

Berger, L., Speare, R., and A.Hyatt. 1999. Chytrid fungi and amphibian declines: 

overview, implications and future directions. In Declines and Disappearances of 

Australian Frogs, ed. A, Campbell. Environment Australia. Pp23-33. 

Biosphere 2005. Bush Regeneration Plan Bareena Wetland, North Avoca. Prepared for 

Gosford City Council. 

Consterdine, K. (1999a). Habitat restoratio n of North Avoca Lagoon for the Green and 

Golden Bell Frog (Litoria aurea). Submitted as Habitat Restoration Module for Bush 

Regeneration IV Course. University of Newcastle. 

Consterdine, K. (1999b). Bushland Management Report on North Avoca Lagoon 

Reserve. Prepared as module on Bushland Planning and Management for Bush 

Regeneration IV Course. University of Newcastle. 

Department of Environment and Conservation NSW (DEC NSW) (2005). Draft 

Recovery Plan for the Green and Golden Bell Frog (Litoria aurea). DEC NSW, 

Hurstville, NSW. 

Miehs, A. 2000. Dietary patterns and prey selection in Litoria aurea and Limnodynastes 

peronii., B. Sc. (Hons) Thesis, University of New South Wales. 

Miehs, A., and G. H. Pyke. 2001. Observations of the foraging behaviour of adult Green 

and Golden Bell Frogs (Litoria aurea). Herpetofauna, 31:94-96. 

New South Wales National Parks and Wildlife Service. (NSW NPWS) 2002. Draft NSW 

Threat Abatement Plan. Predation by Gambusia holbrooki - The Plague Minnow. Draft 

for public comment. March 2002. NSW National Parks and Wildlife Service, Hurstville. 




Penman, T. D. (1998). Natural factors affecting the early life stages of the Green and 

Golden Bell Frog, Litoria aurea: Lesson 1829. BSc Hons Thesis, University of New 

South Wales. 

Pyke, G.H. & White, A.W. (1996). Habitat requirements for the Green and Golden Bell 

Frog Litoria aurea (Anura: Hylidae). In: Pyke, G.H. & Osborne, W.S. (Eds) (Aust. Zool. 

30: 224-232) 

Pyke,G.H. & White,A.W. (2000) Factors influencing predation on eggs and tadpoles of 

the endangered Green and Golden Bell Frog (Litoria aurea) by the introduced Plague 

Minnow (Gambusia holbrooki). Australian Zoologist 31: 496-505. 

Pyke,G.H. and White,A.W. (2001). A Review of the Biology of the Green and Golden 

Bell Frog (Litoria aurea). Australian Zoologist 31: 563-598 

Pyke, G.H., White, A.W., Bishop, P. and Waldman, B. (2002). Habitat-use by the Green 

and Golden Bell Frog (Litoria aurea) in Australia and New Zealand. Australian 

Zoologist 32: 12-31. 

Schuytema,G.S., and A.V.Nebeker. 1999. Comparitive toxicity of ammonium and 

nitrogen compounds to Pacific Tree Frog and African Clawed Frog tadpoles Chemistry 

18(10): 2251-2257. 

Shine, R. (1987). Food habits and reproductive biology of Australian snakes of the genus 

Hemiaspis (Elapidae). Journal of Herpetology 21: 71-74. 

White, A.W. & Pyke, G.H. (1996). Distribution and conservation status of the Green and 

Golden Bell Frog Litoria aurea. In: Pyke, G.H. & Osborne, W.S. (Eds). (Aust. Zool. 30: 

177-189) 

White, A.W. & Pyke, G.H. (1999). Past distribution of the Bell Frogs Litoria aurea and 

Litoria castanea in the Bathurst-Orange District of New South Wales. Herpetofauna 

29:1 -9 

White, A.W. and Pyke, G.H. (2005). Frogs on the Hop: Translocations of Green and 

Golden Bell Frogs (Litoria aurea). Australian Zoologist : In press 




APPENDICES 

Appendix 1: Description and justification for adopted specifications for the 

development of artificial pond breeding habitat for the Green and Golden 


Rationale 

All frogs can use a variety of different water bodies as breeding sites, however, breeding 

success is often determined by the nature of the breeding habitat. In this section, the main 

factors that appear to affect breeding success in Green and Golden Bell Frogs are 

discussed and the design implications for a breeding pond at the Avoca Lagoon are 

explained. 

The main factors affected breeding success appear to be: 

1. Non-static ponds: stable ponds are rarely used as breeding sites by Bell Frogs. Ponds 

that fluctuate in depth, salinity, pH or are ephemeral are more likely to be used as 

spawning sites 

2. Water temperatures: Bell Frogs appear to prefer water temperatures of 20° C or more 

for spawning and tadpole growth 

3. The number and composition of co-occurring frog species: Bell Frogs generally do not 

breed at sites where there are many other frogs present. The largest and most successful 

breeding sites for Green and Golden Bell are where there are no other frog species 

present, or if one is present, it is in low numbers. 

4. The nature of the emergent vegetation: Bell Frogs require diurnal basking sites near 

breeding sites. 

5. The nature of the fringing vegetation: Fringing vegetation provides the foraging habitat 

for Bell Frogs congregating around breeding ponds. 

6. The proximity of refuge habitat for juvenile frogs: Bell Frogs are highly cannibalistic. 

Juvenile Bell Frogs may be eaten by adult frogs if there are no sites available where 

juvenile frogs can escape adult predation. 

7. The proximity of other water bodies: Bell Frogs move about between water bodies. 

Female Bell Frogs, in particular, are constantly on the move between sites. If the nearest 

water body is a long distance away from the breeding pond, the chances of females 

reaching the breeding pond during favourable weather conditions is reduced and breeding 

may not occur. 

Pond Size: 

Pond sizes are not fixed and will depend on the nature of the available land. In general, 

the larger the pond, the more space is created for emergent and fringing habitat, and more 

frogs can be sustained around the pond. The optimal size for artificial ponds is 25 metres 

long (east-west) and 15 metres wide (i.e. each pond will have a surface area of 375 sq. 

metres). A pond of this size is not possible for the Bareena Wetland (for reasons outlined 

in 4.1) and so a much smaller pond has been designed for the available space. Being a 




smaller pond, it will provide limited shelter and foraging habitat but will be a release 

pond for tadpoles (if approved by DEC) as well as a possible supplementary breeding 

pond under certain conditions. Similarly, the preferred site for breeding ponds at 

Davistown does not permit the excavations of large ponds and so the emplacement of 

more than one above-ground ponds has been recommended. 

Pond Depth: 

Bell Frog ponds should have very limited shallow margins and have areas of open water. 

To achieve these features, the pond will need to be relatively steep-sided and have a 

minimum depth of 1 metre. This can be achieved through the use of rock slabs to form 

the walls of the ponds or by using pre-fabricated materials. In some circumstances, 

above-ground swimming pools can be used. If a sheer sided pool is used, rocks and 

climbing surfaces will have to be created inside the pond so that frogs are able to get out 

of the pond. 

Pond Water Levels: 

Creating a non-static pond environment can be achieved through varying water levels 

and/or periodic draining of the ponds. To permit the control of water levels in the pond, 

the pond should be easily drainable. This is usually best achieved by placing a riser in the 

base of the pond and having a discharge pipe passing through the floor of the pond to the 

outside. A manual control valve can be placed on the discharge pipe so that the water 

level in the pond can be lowered or dra ined as required. 

Studies of Bell Frog behaviour (e.g. Pyke & White 1999) have shown that Bell Frogs can 

be displaced from stable aquatic habitat areas but fare much better when ponds are 

fluctuating or ephemeral. Because of this behaviour and other aspects of the biology of 

Bell Frogs, they are considered to be a “colonising species” (White 1995, Pyke & White 

2001). In newly established aquatic sites, Bell Frogs are better able to survive and avoid 

direct competition with other species whereas in well-established and near-permanent 

ponds other species may dominate (Pyke & White 1999). This means that periodic 

management of the ponds will be required if they are going to continue to be used by Bell 

Frogs. 

Another reason for installing drains is to be able to rid the ponds of unwanted pests, in 

particular Plague Minnows Gambusia holbrooki. These small fish are widespread in the 

area and are known to prey on the tadpoles and eggs of Green and Golden Bell Frogs 

(Pyke & White 2000). They can be transported between aquatic sites by birds and so the 

frog ponds may become infested with the fish in the future. Should Gambusia be found in 

a pond, it should be drained during the next winter and the fish killed. If the fish are 

allowed to remain in a pond, the chance of them being transported to another pond is 

high. 

Pond Walls: 




The walls of the pond need to be relatively steep. This can be achieved through the use of 

sandstone boulders and rocks, gabion or reinforced metal or by using a prefabricated 

pond with tall straight sides. 

Number of Ponds: 

By having more than one drainable pond, it will be possible to manage the frog ponds so 

that at least one of the ponds is functioning as a newly established pond. During the 

winter of each year, one pond will be drained and allowed to become dry. Much of the 

surrounding emergent vegetation will regress and some will die. In August, the pond will 

be refilled and the natural succession of aquatic plants allowed to proceed. The choice of 

pond to drain will depend on how much vegetation is around the pond and what frog 

activity is like at the pond. If a pond is thickly vegetated and only a few Bell Frogs are 

detected in the pond during the monitoring sessions, that pond should be drained. If ponds 

are sparsely vegetated and Bell Frogs are active about the pond, it should be retained. 

Ponds should not go longer than three (3) years before being drained and re-established. 

The decision to drain a pond should be made in consultation with the project’s 

herpetologist. The herpetologist will need to determine which pond is to be drained and 

when draining could commence. If there are tadpoles in the pond, it should not be drained 

unless the tadpoles can be successfully relocated to a neighbouring pond. 

Emergent Vegetation 

Emergent plants should be planted in clumps (or kept in submerged pots) in each of the 

ponds. These plants serve several purposes: 

* shelter for frogs during the day; 

* basking sites for frogs during the day; 

* insect attractants (i.e. food for the frogs). 

The plants chosen for the ponds are all multiple stemmed, erect rushes. They will all grow 

in the newly created ponds. After a few years they will become too thick and need to be 

reduced. At this stage, the pond would be drained and the plants allowed to die back. It is 

not anticipated that manual harvesting of the planted emergent plants will be required. 

Recommended plants: 

Jointed twig-Rush Baumea articulata 

Sedge 

Schoenoplectus mucronatus 

Sedge 

Schoenoplectus validus 

Spike Rush 

Eleocharis sphacelata 

Herbicides will not be used around the ponds. 




Fringing Vegetation 

Fringing vegetation provides shelter habitat as well as foraging areas close to the breeding 

ponds. As adult Bell Frogs feed mainly on large arthropods, often the most suitable 

foraging habitat is overgrown grassland. In many of the sites where Bell Frogs occur, 

these grasses are exotic, such as Kikuyu and Buffalo Grass. These grasses appear to be 

particularly suitable as they grow quickly, are eaten by a variety of crickets, grasshoppers 

and other invertebrates, and create their own micro-habitats when allowed to become 

overgrown. Native grasses rarely grow thickly enough to create a dense foraging area. If 

native grasses are used, they should be allowed to become long and straggly. 

Recommended plants: 

Themeda australis 

Austrodanthonia sp. 

Lomandra longifolia 

Kangaroo Grass 

Wallaby Grass 

Matt Rush 

Shelter 

Shelter for Bell Frogs can be provided in several forms; as emergent plant cover around 

the ponds, as rock piles around the ponds, as tussock thickets (such as overgrown grass or 

multi-stemmed ground cover plants), logs and timber and rock piles on the grassed area. 

Bell Frogs are preyed upon by a variety of predators. At Avoca and Davistown, the main 

predators are likely to be birds, such as White-faced Herons, Australian White Ibis, 

cormorants and egrets. These birds are most likely to visit the ponds when the vegetation 

levels are low (e.g. when a pond is being dried out or refilled). 

If there are tadpoles in the ponds, birds will prey upon the tadpoles. If the vegetation is 

low and does not protect the tadpoles, flutter ribbons will be suspended above the ponds 

to deter the birds, as has been done at the Marrickville Bell Frog pond. 

Foxes may constitute the other main potential predator. At this stage no measures are 

considered for the control of foxes but this may change according to the outcome of frog 

monitoring. Foxes have been shown to predators of Bell Frogs and, in some sites (e.g 

Homebush Bay), control programs have been adopted to regulate these animals. 

Movement Corridors 

Bell Frogs need to be able to move safely between ponds and between foraging areas. 

This can be achieved (especially in highly urbanised or industrial sites) by the creation of 

movement corridors. Fortunately at Avoca and Davistown, natural movement corridors 

are present and do not need to be created (but need to be protected). 

If artificial movement corridors are required they may consist of a broad, grassed strip 

with a central swale. The central depression in the swale would be a low, wet region 

running along the length of the corridor. The grasses used to plant out the corridor can be 

native tussock grasses. The swale should be regularly supplied with water or the corridor 




could be lined with sprinklers. At 100 metre intervals along the corridor a shallow, 

temporary (“Stepping Stone”) pond should be created. The ponds will only be 5 metres 

long and 50 cm deep. They will be lined with rocks and tussock plants, such as Lomandra 

longifolia. 

Green and Golden Bell Frogs are a very mobile frog species. They have been recorded 

undertaking long distance movements overnight and over sustained wet periods (Pyke & 

White 2001). This mobility allows Bell Frogs to periodically move between neighbouring 

sites. 

The Bareena Bell Frog Pond 

The location of a frog pond near the Bareena Wetland is greatly limited by the space and 

other land uses around the wetland. There only appears to one suitable location for the 

pond and this is in the north-eastern corner of the wetland site (Figure 1-1). This location 

is chosen for three reasons: 

1. There is sufficient space between the grassed walking areas and the wetland to 

locate a small pond, 

2. On the northern side of the wetland, over-shadowing by trees will be 

minimised, 

3. An intermittent supply of freshwater may be available from re-directed 

stormwater, alternatively freshwater may be sourced from bore water or a water tank that 

includes its own catchment roof. 

The advantage of creating the breeding pond so close to the wetland is that many of the 

aspects of habitat creation are already present. Shelter sites for juvenile frogs and 

foraging habitat are already present (although in limited amounts). The proximity of the 

breeding pond to the wetland also ensures that female frogs are likely to be in the area 

during breeding times. 

The Bareena pond will consist of a bunded, slightly elevated embayment within the 

wetland. At present, the wetland is particularly suitable for Bell Frogs because of the 

periodic saline infusion into it. The brackishness of the water prevents other frog species 

from dominating the wetland and permits Bell Frogs to breed during episodes of low 

salinity (usually following local heavy rain). The freshwater influshing may often be 

insufficient to permit Bell Frogs to breed or may not persists long enough for the tadpoles 

to complete development before salt levels begin rising in the water. The purpose of the 

Bareena pond is to provide a freshwater site that lasts longer than the present areas of the 

wetland that are used by Bell Frogs. This site would be suitable for the relocation of 

tadpoles should it be required and as another potential breeding site. 

If the base of the Bareena pond is slightly higher than for the wetland, it will retain 

freshwater for longer, but will also dry out during sustained dry spells. The base of the 

pond will be about 10 cms higher than the level of the wetland. 




Stormwater can be re-directed from the residential lots nearby to provide a freshwater 

surge into the breeding pond following rain. Surface stormwater can be collected is a 

broad, shallow, grassed surface channel and directed into the frog pond. A spillway will 

have to be created in the breeding pond so that surplus water does not damage the pond 

walls and is diverted into the main wetland. 

Figure A1-1 

Preferred Location of the Bareena Bell Frog Breeding Pond 




Figure A1-2 

Schematic Profile of Bareena Bell Frog Breeding Pond 

The Bareena pond will only be 8 metres long (east-west) but will only be 3 meters wide 

(north-south) and will be elliptical in outline. The center of the pond will only be between 

30 and 50 cms deep. The pond will need to enclosed by approved security fencing that 

will stop passers by and would-be vandals from entering the pond but still allow frogs to 

pass through. 

The Bareena pond will need to have clay imported to form the base of the pond. A low 

bund, approximately 60 cms high will be formed along the southern side of the pond and 

this will be the main barrier between the wetland and the breeding pond. A small spillway 

will be created to the side of this bund to allow excess water to spill over into the wetland 

without damaging the pond wall. The northern side of the pond will be flush with the 

existing ground level, the two side walls will start at ground level and extend out to the 

southern bund wall. In order to stabilise the pond walls and to keep them relatively steep, 

rock or large rubble pieces may be required to be added to the wall mass. 

Stormwater flow entering the pond will come from the northern side of the pond. 

Alternatively options to use bore water or collect rainwater may be explored. Stormwater 

supply may be via buried pipes from adjoining properties or may be as overland flow. 

The extent to which stormwater may be rediverted has yet to be determined, and the 

mechanism for rediverting the flow will depend on the volume available. 




It is anticipated that tall, emergent plants (such as Eleocharis) will be planted at the 

southern end of the pond. The southern end of the pond is more likely to retain freshwater 

than the northern end. The ponds banks will be grassed and planted with clumps of 

Lomandra. If logs or rocks are available, additional shelter sites will be created around 

the bund wall and pond edges. 

Davistown Frog Habitat Area 

In 6.2, three areas were identified as sites for the creation or enhancement of habitat for 

Green and Golden Bell Frogs. Each area has advantages and disadvantages, and each is 

considered below so that areas can be prioritized. 

Malinya Site: 

The Malinya Site (also known as the Oystergrowers Site) is in West Davistown (Figure 

13). Bell Frogs have never been recorded at this site but it has several attributes that make 

it a potential habitat area. The Malinya Site is on Counc il-owned land and is removed 

from residences or other developmental threats. The site is also large and not confined by 

alternate land uses. The major disadvantage of the site is that considerable earth works 

would be required to alter the surface stormwater run-off and direct this into ponds or 

other wetland areas. The Malinya Site may be an ideal site if habitat has to be created 

anew and populations are declining elsewhere but there are some uncertainties as to 

whether Bell Frogs would colonise it as they have not been recorded previously in this 

area. 

Pine Avenue Reserve: 

Pine Avenue Reserve is in East Davistown and is close to areas where Bell Frogs have 

been recorded. Its location is its greatest attribute, along with the land tenure, being 

Council-owned land. The disadvantages of the Pine Avenue Reserve are its small size, 

proximity to a relatively major road that is likely to result in frog roadkills and difficulties 

in altering habitats due to sensitive ecosystems nearby. Pine Avenue would be considered 

as potential location for the expansion of the Bell Frog population at Davistown. 

Ilumba Wetland: 

The Ilumba Wetland is also in East Davistown and is a site where Bell Frogs have been 

recorded. It has a reasonable amount of space for development but is constrained by 

residences on one side and salt marsh and freshwater wetlands on the other. Soil testing 

has been carried out and the site found to have no underlying acid sulphate soils. 

Freshwater for recreated ponds or habitat areas could be obtained as roof run-off from 

nearby residences (especially 1 Ilumba Avenue) or a rain tank with its own catchment 

roof. Also it adjoins a Council owned lot that could provide easy access and a corridor 

linkage to the nearby known breeding area. 




In view of the attributes of each site and the likelihood that only one site will be 

developed in the near future, the Ilumba Wetland site appears to be the optimal location 

for habitat creation. 

Habitat Priorities 

The limited survey data available makes it plain that breeding by Bell Frogs at Davistown 

is very risky and is often unsuccessful; 1995 was an unusual year in that tadpole survived 

to metamorphosis and some juvenile frogs appeared to have also survived. The next 

known successful breeding event did not take place until 2005. Foraging habitat is 

abundant in the Ilumba Wetland, Romford Wetland and Magnolia Wetland; these 

wetlands also contain adequate shelter areas. Overall, the lack of secure breeding sites at 

Davistown appears to be the major factor in limiting population growth. 

Strategy for Habitat Development 

It is proposed that one or more above-ground ponds be installed in the area behind No 1 

and No 3 Ilumba Avenue (Figure A1-3). The ponds will need to be at least 60 cms deep 

and have a reinforced base. The ponds can be circular or elliptical in outline but should 

have a surface area of at least 50 square metres (i.e. a circular pond 4 metres in diameter 

or an elliptical pond that is 6.5 metres long and 3 metres wide). It is recommended that a 

10 cms layer of clay be placed over the base of the pond to further protect it and that 

rocks be positioned inside the walls to form a platform for pots that hold emergent plants. 

Rocks may also be placed around the outside of the pond to provide a means for frogs to 

enter the pond. It must be noted that in order to prevent ground-dwelling frogs from 

colonizing the pond, the rocks should not form a ramp into the pond, instead they should 

form a series of 20 cm high steps leading up t the rim of the pond. Stepped rock s will 

need to be similarly placed inside the pond to allow frogs to escape the pond (Figure A1- 

4). 

The site for the pond will need to be leveled, probably by the addition of a sand layer 

over the existing grass. Pre-fabricated ponds can be quickly installed but the addition of 

the clay base and rocks will require the use of a small bobcat or backhoe. Spike rushes 

(Eleocharis sphaeculata) can be established in submerged pots around the perimeter of 

the pond. It is preferable to contain the plants in pots so that their roots do not penetrate 

and damage the pond liner. The center of the pond should be open water. 




Figure A1-3 

Preferred Location of the Ilumba Wetland Bell Frog Breeding Pond and Habitat Area. 

Figure A1-4 

Schematic Profile of an Ilumba Bell Frog Breeding Pond 




The areas around the pond can be developed to provide shelter habitat nearby. This will 

consist mainly on planning clumps of Matt Rush Lomandra longifolia around isolated 

rock piles. 

The pond will need to be enclosed by safety fencing. The fencing will keep vandals out 

but will still allow frogs to pass in and out unimpeded. 

A main water supply will be required to service the pond. However, if the pond is to be 

dynamic and to fill quickly during periods of local rain, roof run-off will need to be 

diverted into the pond from the nearby houses. This can be simply achieved by 

redirecting stormwater from the sheds and garages alongside the wetland, into the pond. 

This will require the permission of landholders and possible compensation. The pond 

will need to have a spillway so that when it overflows it will not disrupt frog shelter 

habitats. A mains water supply will also be needed to fill the pond during sustained dry 

periods 

Some bush rehabilitation works will also be required in the Ilumba Wetland to ensure that 

Bell Frog habitat is not overtaken by weeds and movement corridors blocked off. In 

particular, the easement leading to Ilumba Avenue needs to be maintained as a viable 

corridor and invasive weeds, especially vines are kept under control. In other parts of the 

wetlands, bridal creeper, morning glory and asparagus fern have colonised the edges of 

the wetland; these plants need to be controlled as well. 

The Magnolia and Romford wetlands also contain these invasive weeds, as well as 

Spikey Rush Juncus acutus. Routine maintenance will be required to ensure that Bell 

Frog habitat is not lost to the uncontrolled spread of these vigorous weeds. 




Appendix 2: 

Avoca 

Water/ tadpole and Frog Surveys at North 

Methods 

Regular surveys of frogs, tadpoles and water conditions have been carried out at North 

Avoca since November 1998 by interested residents, Council officers and staff from the 

Australian Reptile Park and frog enthusiasts under the supervision of Dr Graham Pyke 

(Table A2-1). Until the end of 2002 these surveys have taken place throughout the year 

at intervals of about seven weeks with 7-8 surveys per year. After that date, surveys have 

not been carried out during winter (i.e. Jun-Aug) and there have been six surveys per year 

(Table A2-1). 

Because of limitations of access to private property, it has not been possible to survey all 

locations throughout the study period. Regular surveys have been carried out at Bareena 

Wetland and within the Nature Strip throughout most or all of the study period (Table 

A2-2). Surveys have also been carried out at 12 Lakeshore Drive throughout this period, 

but they have been irregular in timing. Regular surveys were carried out at 22 Ocean 

Street over about a one-year period and within 35-39 Lake St over about 3 ½ years (Table 

A2-2). 

Each survey took place over a two day period (Table A2-1). Surveys of frogs were 

carried out over two successive nights. Surveys of tadpoles and water conditions were 

carried out during the daytime, usually on the first day. 

Frog surveys have commenced each night a short time after sunset and have, until the end 

of 2004, included two census periods, each lasting about one hour. A prescribed area is 

searched for frogs during each census period and, with the exception of one frog species, 

an attempt is made to capture as many frogs as possible. These frogs are placed in plastic 

bags, one per bag, and taken to a central point for processing, as described below. When 

the Striped Marsh Frog is abundant, as it often is, individuals of the species are generally 

counted but not captured. Frogs that are captured during the first census period are 

processed at the end of this period, but retained in their plastic bags until the end of the 

evening. When this processing is complete there is a second census period during which 

further frogs are captured. After the second lot of frogs had been processed all of the 

captured frogs were released close to where they were captured. Since the beginning of 

2005 there has been just one census per night. 

During processing, each frog is identified, sexed and weighed. In addition, individual 

Green and Golden Bell Frogs and Green Tree Frog, if sufficiently large (i.e. >40mm 

snout-vent length), were implanted with a uniquely-coded microchip. During processing, 

a scanner is used to record the code for any frog that has already been microchipped. In 

this way, individual frogs can be followed through time and space. Such capturerecapture 

also permits estimates of population size to be obtained. 




During tadpole surveys a standardized-net (i.e. swimming-pool net) is swept through the 

water in the wetland a certain number of times (usually 10). Any tadpoles, fish or aquatic 

invertebrates are identified to the lowest possible taxonomic level and counted. The 

snout-event lengths are measured for up to about 10 tadpoles of each species present. 

During the day when the tadpole surveys are carried, a Yeo-kal water meter is used to 

measure a number of water parameters at three locations within the wetland (i.e. 

southeast, southwest, north) and in the lagoon. In this manner estimates are obtained for 

the following: turbidity, dissolved oxygen, pH, salinity and water temperature. In 

addition, the maximum depth for the wetland is recorded. 

These surveys have been carried out by a team of people coordinated by Dr. Graham 

Pyke of the Australian Museum. This team has varied in composition over the years with 

other survey leaders including Melanie Bannerman and Liz Phelps (both of Department 

of Conservation) and Al Mucci and Liz Vella (both of Australian Reptile Park). 

Participants from Gosford City Council have included Rachel Lonie and John Allen. In 

addition, a large number of volunteers, mostly from the local community, have joined in 

the surveys. 

Results 

Water characteristics 

Interpretations of water characteristics in the Bareena Wetland are based heavily on water 

measurements obtained from the southwest corner of the wetland. Measurements were 

taken at the three locations in the wetland on many occasions but the south-west corner 

was sampled most often. As measurements taken at the three sites generally did not differ 

greatly, the greater number of measurements taken at the south-west corner provides a 

stronger data set for the wetland. 

With the exception of water temperature, none of the water parameters has exhibited any 

significant seasonal effect (e.g. salinity: P=0.89; ANOVA). Water temperature has 

followed the usual seasonal pattern, being greatest on average during summer and lowest 

during winter (Fig. A2-1; P=0.000; ANOVA). 

Water temperature in the wetland during breeding season has been sufficiently high to 

support growth and development of Green and Golden Bell Frog tadpoles. During the 

spring/ summer breeding season, water temperatures have almost always been above the 

minimum threshold of 20 C 0 for tadpole growth and development, and average water 

temperature has exceeded 22 C 0 (Fig. A2-1). 

Salinity in the wetland has mostly been either marginal or too high to support breeding by 

the Green and Golden Bell Frog (Penman 1998). Salinity varied between 6-8 ppt on 34% 




of occasions and was above the critical threshold of 8 ppt on 31% of occasions (Fig. A2- 

2; total no. of occasions=35). Average salinity in the wetland has been 6.9 ppt. 

Salinity in Avoca Lagoon has been almost always too high to allow breeding by the 

Green and Golden Bell Frog (Fig. A2-2). 

Maximum depth in the wetland has varied considerably and the wetland has occasionally 

dried out completely (Fig A2-3). On two occasions during the regular surveys the 

wetland was dry (Fig. A2-3); it may have been dry at other times as well. 

Water is apparently able to move between the lagoon and the wetland, presumably by 

percolating through the wall that separates these two water bodies, and the water levels in 

the lagoon and the wetland are generally very similar. When the lagoon is artificially 

drained, its water level drops precipitously and, after a short lag, the water level in the 

lagoon does likewise. After rainfall, the water levels in the lagoon and the wetland rise 

together. A significant positive correlation has been observed between the salinities in the 

lagoon and the wetland. 

The wall that separates the lagoon and the wetland does, however, apparently restrict the 

flow of water between the two, as salinity in the lagoon has always exceeded that in 

wetland (i.e. 15.4 vs 6.9 ppt; P=0.000, ANOVA). 

Other water parameters (i.e. turbidity, dissolved oxygen, pH) have also varied 

considerably, but always within the range of apparently suitable levels for tadpoles of the 

Green and Golden Bell Frog. With regard to these parameters, tadpoles of this frog 

species are apparently tolerant of a relatively wide range of conditions. 

The factors responsible for determining the spatial and temporal patterns in water salinity 

are not clear. Presumably there is movement of water between ocean, lagoon and wetland 

via the water table and the permeable wall between the lagoon and the wetland. Rainfall 

within the catchments of the lagoon and the wetland would result in influxes of 

freshwater, with very low salinity, into these waterbodies. A dynamic balance probably 

exists in the wetland between the effects of evaporation and influxes of salty water and 

freshwater. Further investigation of these processes would be worthwhile. 

Frog numbers 

A total of 8 frog species, including the Green and Golden Bell Frog, have been detected 

within the Bareena Wetland area (Table A2-3). One species, the Common Brown Froglet, 

has been heard but not seen; all other species have been captured (Table A2-3). Some of 

these frog species have been detected in locations outside of the wetland, but no 

additional species have been detected in these locations. 

The Striped Marsh Frog is undoubtedly the most abundant frog species at North Avoca. 

Within the wetland area and in other locations outside of the wetland, it accounted for 




most males heard calling and most tadpoles captured (Table A2-3). It was outnumbered 

within the wetland area by the Green and Golden Bell Frog in terms of numbers captured 

and/or observed (Table A2-3), but surveys there were biased away from it. Outside of the 

wetland, it accounted for most of the frogs observed, almost all of the frogs heard calling, 

and all of the tadpoles recorded. 

In addition to the Striped Marsh Frog, two other frog species, the Green and Golden Bell 

Frog and the Bleating Tree Frog, have also been reasonably abundant at North Avoca. 

Most of the frogs captured during the surveys, which were biased only away from Striped 

Marsh Frogs, were Green and Golden Bell Frogs (Table A2-3). The Bleating Tree Frog is 

a relatively arboreal frog species that would be under represented in our captures and 

large choruses of calling males of this species have been occasionally heard. These three 

species have accounted for all of the tadpoles and immatures recorded so far (Table A2- 

3). 

Successful breeding has been recorded at North Avoca for three frog species, including 

the Green and Golden Bell Frog. Within Bareena Wetland, calling, tadpoles and 

immature Striped Marsh Frog, Green and Golden Bell Frogs and Bleating Tree Frogs 

have been recorded (Table A2-3). In other locations, all recorded tadpoles and almost all 

calling males have been Striped Marsh Frogs. 

All but one of the frog species at North Avoca breed primarily during spring and summer. 

Calling and tadpoles of the above three species have been recorded mostly during this 

period (Table A2-4). Calling by all other species, except the Common Eastern Froglet 

Crinia signifera, has been mostly recorded during this same period. On the other hand, 

calling by the Common Eastern Froglet has mostly been recorded during winter. This 

species generally breeds during winter, whereas all the other species generally breed 

during spring and summer. 

Breeding by the Green and Golden Bell Frog at North Avoca has been restricted to the 

Bareena Wetland. Both calling and tadpoles were recorded here (Table A2-3), but neither 

have been recorded in any other location within North Avoca. There are no other areas 

within North Avoca that appear generally suitable for breeding by this species. 

Successful breeding by the Green and Golden Bell Frog has occurred in just three of the 

seven breeding seasons included in the study and has not reflected the observed 

frequency of calling by this species. Tadpoles of this species were recorded during the 

98/99, 00/01 and 03/04 breeding seasons and not at other times (Table A2-5). All 

captured immatures were considered to have arisen from these same breeding seasons 

(Table A2-5). In three breeding seasons, there was calling recorded but no tadpoles or 

immatures (Table A2-5). In one season tadpoles and immatures were recorded, but no 

calling (Table A2-5). 

Across the seven breeding seasons included in the present study, tadpoles and male 

calling for the Green and Golden Bell Frog have been infrequently recorded and have 

only occurred when the water temperature has been above 20 C 0 and salinity has been 




less than 8-9 ppt (Table A2-6). Calling by males of the species has been recorded on just 

seven out of 22 occasions during spring or summer when water parameters were 

measured, with associated water temperatures exceeding 20 C 0 and associated salinities 

less than 9 ppt (Table A2-6). Tadpoles of the species have been recorded on just six out 

of the 22 occasions, with associated water temperatures exceeding 23 C 0 and associated 

salinities less than 8 ppt (Table A2-6). These results are consistent with results from other 

sites (Pyke and White unpubl). 

The observed densities of Green and Golden Bell Frog tadpoles have been relatively low. 

For those occasions when tadpoles of the species have been present, the observed average 

tadpole density for the species has been about 0.009 tadpoles per litre (n=80 sweeps, 

length per sweep=120 cm, net cross-section area = 600 sq cm) which is low in 

comparison with other sites (e.g. at Broughton Island, for example, the tadpole density 

for the Green and Golden Bell Frog has averaged about 0.5 tadpoles per litre when 

present; Pyke unpubl.). 

Green and Golden Bell Frogs have been found in all available habitat areas at North 

Avoca. During the surveys, most immatures and adult frogs of this species were captured 

and/or observed within the wetland or adjacent nature strip, but some were also recorded 

from various urban yards (Table A2-7). The wetland and nature strip have, between them, 

accounted for 74% of captures of adults and 81% for immatures. Across all locations, 

about 20% of captures have been of immatures, with little or no difference between 

locations (Table A2-7). These immatures presumably originated in the wetland and 

subsequently moved from there into the other locations (see below). In addition, local 

residents have reported seeing this species along some of the streets and in other urban 

yards. 

These capture numbers do not necessarily, however, reflect differences in abundance 

between the various locations and areas. Frogs were probably not equally likely to be 

encountered or captured in the different locations. Only a small proportion of urban yards 

were surveyed and surveys at these locations were not continuous throughout the study 

(Table A2-2). 

The numbers of frogs captured during the surveys have followed a similar seasonal 

pattern to breeding, with capture numbers being generally highest in summer and lowest 

in winter. 

The estimated number of adult Green and Golden Bell Frogs living at North Avoca is 

about 100. It is not known how much the population size varies under more favorable or 

more adverse conditions. 

Frog movements 

When Green and Gold en Bell Frogs were recaptured over successive nights they were 

found to have changed location by more than 10 metres on only about 14% of occasions 




(Table A2-8). Such movement was not significantly affected by an animal’s sex/age 

category (Table A2-8; P=0.14, Chi-Square Test). 

When individual Green and Golden Bell Frogs were found to have changed location 

between successive captures, the distances involved were mostly relatively short, but 

some frogs have exhibited movements over distances of up to about 300 meters. Most 

recorded movements were between the wetland and the adjacent nature strip (Table A2- 

9), a distance generally in the range 20-50m. Two frogs were recorded to have moved 

between the wetland and 22 Ocean Street (one in each direction), a distance of about 

300m (Table A2-9). 

Frog movements between survey periods were much higher with up to 80% of frogs 

being more than 10 metres from the previous site of capture. These and other 

observations indicate that frogs of the species move throughout much of North Avoca. As 

Bareena Wetland is the only known breeding site for the species within North Avoca, all 

frogs of this species must have originated within this wetland at some point in time and 

frogs that have been captured and/or observed at 12 Lakeshore Drive must therefore have 

moved about 600m, assuming they swam across the narrow water channel between 

Tramway Road and Lakeshore Drive (Fig. 1). Had the frogs kept to the land the whole 

way the distance traveled would have been much greater. Movements by individuals of 

this frog species of about 1km have been recorded at Broughton Island (Pyke unpubl.). 

Fish 

During a period when there was a direct connection between the wetland and the lagoon 

when water levels were high, Gambusia and other fish have been occasionally observed 

in the wetland. Between July and October 2000 there was a ditch about 50 cm wide that 

provided a direct water connection between the wetland and the lagoon when water levels 

were high. During this period, Gambusia were captured during the surveys on one 

occasion (i.e. 22 March 2000) and observed at other times as well. No Gambusia or other 

fish have been recorded in the wetland since the wall was repaired and the ditch ceased to 

exist. 

It remains possible for Gambusia to invade Bareena Wetland during times of very high 

water level. During at least one occasion when water levels in the lagoon and wetland 

were very high and increasing because of ongoing rain, there was a broad but shallow 

water connection between the lagoon and the wetland near the southern end of the wall 

that separates the two where the height of the wall is at its lowest. This situation did not, 

however, persist for long as the lagoon and wetland were drained shortly thereafter. 

Disease and other factors 

Disease 

Chytrid fungal disease has apparently been present within the frogs at North Avoca. In 

1998 this disease was detected at the Australian Reptile Park amongst frogs that had 




come from North Avoca (Porter 1999). Frogs that are suffering the effects of this disease 

have not, however, been observed in the wild at North Avoca. It is possible that the 

relatively high salinities in the water at Bareena Wetland have controlled or eliminated 

this disease . 

Other factors 

The opening and closing of the lagoon has a direct effect on the Bareena Wetland, when 

the lagoon is closed and high, the wetlands become saline; when the lagoon is open or 

low, the wetlands may be dry. The timing of the opening and closing of the lagoon may 

determine whether Bell Frogs are able to successfully breed that season. 




There has so far been no evidence of other factors affecting this frog population. There 

have so far been no observations within the study area of the introduced fox, which has 

been observed nearby (e.g. Consterdine 1999b) and could prey on the frogs. A single 

snake, thought to be a Swamp Snake Hemiaspis signata, which is known to eat small 

lizards and frogs (e.g. Shine 1987) has been observed in the vicinity of the wetland (M. 

Bannerman, pers. obs.). Some birds, such as the White-Faced Heron, might also be 

predators of these frogs but they have rarely been observed in the area. There are no 

obvious sources of pollution affecting the wetland. 

The impact of weeds around the wetland is not well understood. Some weeds, such as 

lilies and yuccas, provide good shelter sites for frogs, other weeds, such as Bitou Bush, 

overgrow ground cover plants and destroy frog foraging areas. Other weeds, such as 

kikuyu grass, can provide superior foraging habitat when native grasses are sparse or 

absent. However, despite all these diverse impacts, invasive weed species are generally 

unwanted around Bell Frog sites, especially when there is a native plant species that can 

provide the same habitat component. 

Dogs and cats may also have an impact as they may come across dispersing Bell Frogs. 

Dogs do not appear to take much interest in frogs but cats are instantly attracted to their 

movement at night. Some cats play with frogs, sometimes injuring or killing, others 

ignore them. Dogs may have a more serious impact through faecal contamination of the 

wetland. Animal droppings release ammonium ions as they decompose and tadpoles are 

particularly sensitive to ammonia: it is lethal at very low concentrations (Schuytema and 

Nebeker 1999). 




Table A2-1: Survey dates for North Avoca 

Year Dates 

1998 5-6 Nov, 17-18 Dec 

1999 28-29 Jan, 18-19 Mar, 13-14 May, 8-9 Jul, 11-12 Aug, 22-23 Sep, 3-4 Nov, 

15-16 Dec 

2000 2-3 Feb, 22-23 Mar, 17-18 May, 19-20 Jul, 6-7 Sep, 1-2 Nov, 13-14 Dec 

2001 7-8 Feb, 3-4 Apr, 30-31 May, 25-26 Jul, 12-13 Sep, 31 Oct-1 Nov, 19-20 Dec 

2002 20-21 Feb, 2-3 Apr, 30-31 May, 7-8 Aug, 18-19 Sep, 30-31 Oct, 17-18 Dec 

2003 19-20 Feb, 2-3 Apr, 21-22 May, 3-4 Sep, 29-30 Oct, 17-18 Dec 

2004 11-12 Feb, 7-8 Apr, 26-27 May, 22-23 Sep, 3-4 Nov, 8-9 Dec 

2005 15 Feb , 23 Mar. 

Table A2-2: Periods during which surveys have been carried out at different locations 

in North Avoca 

Location Date: 1 st survey Date: Last survey 

Bareena Wetland Nov 1998 On going 

Nature strip Jan 1999 On going 

22 Ocean St Nov 1998 Sep 1999 

35-39 Lake St May 1999 Dec 2002 

18-22 Bareena Ave May 1999 On going 

Table A2-3: Seasonal patterns of breeding for frogs at Bareena Wetland (Numbers of 

records) 

Season 

L. aurea 

calling 

L. aurea 

tadpoles 

Lim. 

peronii 

calling 

Lim. 

peronii 

tadpoles 

L. dentata 

calling 

Spring 14 2 17 5 4 0 

Summer 6 6 17 3 6 3 

Autumn 1 1 9 2 0 0 

Winter 2 0 5 1 0 0 

L. dentata 

tadpoles 

Table A2-4: 

Breeding by Litoria aurea during different seasons at Bareena Wetland 




Breeding Season Calling males Tadpoles Immatures 

subsequently 

captured 

98/99 ? 1 41 42 

99/00 1 0 0 

00/01 10 2 29 

01/02 9 0 0 

02/03 0 0 0 

03/04 0 8 15 

04/05 8 0 0 

Notes: 1. Many males recorded calling during 5 surveys but numbers not estimated 

Table A2-5: 

recorded 

Water temperatures and salinities when L. aurea calling or tadpoles 

Survey dates L. aurea calling L. aurea tadpoles Salinity 

(ppt) 

Water temp 

(C 0 ) 

5/6 Nov 1998 Yes Yes 3.1 25 

8 Dec 1998 Yes Yes 3.4 23 

17/18 Dec 1998 Yes Yes 3.1 24 

13/14 Dec 2000 Yes 8.0 29 

7/8 Feb 2001 Yes 7.7 29 

12/13 Sep 2001 Yes 4.2 20 

19/20 Dec 2001 Yes 9.0 31 

17/18 Dec 2003 Yes 4.7 28 

11/12 Feb 2004 Yes 7.0 32 

22/23 Sep 2004 Yes 7.4 21 

Table A2-6: Captures of Litoria aurea from different areas within North Avoca 

between Nov 1998 and Mar 2005 

Area 

Number adult 

captures 1 

Number immature 

captures 1 

Bareena Wetland 377 92 

Nature Strip 253 82 

18-22 Bareena Ave 28 11 

35-39 Lake St. 163 16 

22 Ocean St. 26 13 

12 Lakeshore Dr. 4 2 

851 216 

Note: 1. 

Including recaptures 




Table A2-7: Total numbers of recaptures of L. aurea at North Avoca and numbers of 

recorded changes in location between successive captures. 

Age/ Sex # changes in location Total # recaptures 

Adult male 39 239 

Adult female 7 56 

Immature female 1 36 

Immature unsexed 4 39 

Combined 51 (13.8%) 370 

Table A2-8: 

Successive locations for L. aurea captured and recaptured at North Avoca 

1 st Location Bareena 


2 nd Location 

Nature Strip 35-39 Lake 

Street 

18-22 

Bareena 

Avenue 

Bareena 124 20 12 1 1 


Nature Strip 8 80 1 1 0 

35-39 Lake 1 3 90 0 0 

Street 

18-22 2 0 0 10 0 

Bareena Ave 

22 Ocean St 1 0 0 0 15 

22 Ocean 

Street 




Fig. A2-1: 

Average water temperature (C 0 ) vs Season 




Fig. A2-2: Frequency distributions of observed salinities in Bareena Wetland and 

Avoca Lagoon 




6 

5 

FREQUENCY 

4 

3 

2 

1 

0 

0 20 40 60 80 100 120 

MAXIMUM DEPTH (cm) 

Fig. A2-3: 


Frequency distribution of observed maximum depths (cm) in Bareena 




Appendix 3: 

Methods 

Water/ tadpole and Frog Surveys at Davistown 

Surveys for frogs, tadpoles and water parameters at Davistown have been opportunistic in 

nature (Table A3-1). Sometimes they have been carried out because appropriate 

personnel and equipment were in the area for some other reason. Other times they have 

been carried out in response to a significant rainfall event or a reported sighting of the 

Green and Golden Bell Frog. Surveys undertaken in 2005 were undertaken by the 

Australian Reptile Park supported by a research grant from Gosford City Council. 

The surveys have been carried out by a variety of people, including Dr. Graham Pyke, 

Melanie Bannerman, Al Mucci and Liz Vella (Australian Reptile Park). For purposes of 

this management plan, reported observations by other people are also included. 

Results 

• Water parameters 

The few measurements of water parameters for wetlands in Davistown suggest that these 

wetlands are generally relatively saline, but occasionally suitable for breeding by the 

Green and Golden Bell Frog or Striped Marsh Frog (Table A3-2). On two occasions, 

once in the Magnolia Wetland and once in the Ilumba Wetland, the observed salinity was 

just below the upper threshold of 8 ppt for breeding by these frogs (Table A3-2). In the 

case of this Ilumba wetland, tadpoles of the Striped Marsh Frog were recorded in the 

water at this site at the same time (see below). In the case of the Magnolia Wetland the 

fish Gambusia were present (see below), and may have prevented tadpoles from being 

present. On other occasions the observed salinity has been too high to support frog 

breeding (Table A3-2). 

• Tadpoles and fish 

Tadpoles of the Green and Golden Bell Frog were first recorded at Davistown in 

February 2005. For the previous six years of survey, the only frog species for which 

tadpoles were recorded was the Striped Marsh Frog (Table 2). During surveys at 

Davistown, tadpoles of this species have been encountered in one of the wetland areas 

(Table 2 ) and in several garden ponds (G. Pyke, pers. obs.). In the former case, the 

salinity in the presence of the tadpoles was 7.3 ppt (Table A3-2). 

Gambusia has been recorded twice during surveys, each time in the Magnolia Wetland 

area (Table A3-3). It has also been observed in roadside drains near the Magnolia 

Wetland (G. Pyke, pers. obs.). 

• Frogs 




At Davistown a total of 5 frog species, including the Green and Golden Bell Frog, have 

been observed and/or recorded calling during surveys over the last six years (Tables A3-3 

& A3-4). It is not possible to assess the relative abundance of each of these species, 

though the Striped Marsh Frog is almost certainly the most abundant species, as it has 

been detected throughout Davistown and is almost always detected somewhere in the 

area. 

The Green and Golden Bell Frog is apparently presently restricted to a relatively small 

region in southeast Davistown (Fig. 4). Over the last six years, all the observations of this 

species in Davistown have been made in the region that lies to the southeast of the 

intersection between Pine Ave and Kincumber Crescent and is bounded by Cockle 

Channel (Fig. 4). Within this region, observations have been scant and scattered. 

Calling by males has indicated that the Green and Golden Bell Frog has attempted, at 

least twice during the last six years, to breed in the vicinity of one specific location within 

this region. This species has been recorded calling near the north-western edge of 

Kincumber Crescent opposite Romford Close (Fig. 4; Table A3-3), once from within the 

edge of the wetland and once from the open roadside drain that extends from the wetland 

along the front of the adjacent urban block (Fig. 4; Table A3-3). It has not been recorded 

calling at any other location in Davistown. 

Until recently, it seemed likely that the species has been unable to breed successfully in 

Davistown for at least the last six years and that its population here has consisted, during 

this period, only of a small group of aging adults. All confirmed observations of the 

Green and Golden Bell Frog in Davistown during this period have been of adults and the 

numbers encountered at any one time have been low ( Table D03). There had, until very 

recently, been no confirmed observations of either tadpoles or immatures of this species 

(Tables A3-2 & A3-3). 

However, the finding of tadpoles and juvenile frogs in February/March 2005 has 

demonstrated that Green and Golden Bell Frogs can breed successfully in Davistown, 

although the frequency of breeding is still unacceptably low. Juvenile Bell Frogs were 

reported to have been observed in the front garden of 30 Magnolia Ave in 1985 (A. 

Knock, pers. comm.). In 1998, immature Bell Frogs were again recorded at 30 Magnolia 

Ave (Table A3-3). 

There is presently no available information concerning movements by individual frogs 

within the Davistown area. So far only three Green and Golden Bell Frogs have been 

micro-chipped in the area and none of these have been recaptured (many frogs have been 

microchipped at each survey night over 2005 - need data from Reptile Park, I understand 

this was provided to Graham). This situation should, however, improve with further frog 

surveys coordinated by the Australian Reptile Park. Capture/recapture observations 

carried out during these surveys will probably demonstrate that these frogs move 

throughout the wetland and urban landscape, sometimes over distances of 1km or more, 

as they do at North Avoca and elsewhere (Pyke and White 2001). 




• Disease and other factors 

There is no evidence to suggest that the frogs at Davistown are significantly affected by 

other factors. Foxes are rarely observed in the area. Frogs exhibiting signs of disease 

have not been observed here. Potential avian predators have occasionally but not 

commonly been observed in the area. 




Table A3-1: 

Records of salinity, water temperature and maximum depth at Davistown 

Location 

Date 

Code 

13/10/1998 PINE AVENUE 

RESERVE 

13/10/1998 MAGNOLIA 

WETLAND 


WETLAND 

03/04/2003 ILUMBA 

WETLAND 

Salinity Water 

(ppt) Temp ( 0 C) 

26.85 29.4 

12.54 22.8 

6.70 27.3 

7.33 19.5 16 

Max 

Depth (cm) 

Table A3-2: 

Records of tadpoles and the fish, Gambusia during surveys at Davistown 

(Observer: G. Pyke) 

Date 

Location Animal AnimalSpecies 

Code 

Type 


TADPOLES Striped Marsh Frog 

WETLAND 


FISH Gambusia 

WETLAND 


FISH Gambusia 

WETLAND 

03/04/2003 ILUMBA WETLAND TADPOLES Striped Marsh Frog 

Table A3-3: Records of Green and Golden Bell Frog at Davistown since 1998 

Date 

Location Code 

31/03/1998 23A 

MAGNOLIA 

31/03/1998 23A 

MAGNOLIA 

Life 

History 

Stage 

Sex 

How 

Detected 

Observer(s) 

Number 

ADULT OBSERVED 2 G. Pyke; R. 

Wellington 

ADULT OBSERVED 1 G. Pyke 

07/02/2002 KIN ROM ADULT OBSERVED 1 P. Shelley 

07/02/2002 KIN ROM ADULT M CALLING 4 P. Shelley 

25/12/2002 1 ILUMBA ADULT OBSERVED 1 M. & D. 

McGinlam 

10/03/2003 1 ILUMBA ADULT OBSERVED M. & D. 




Date 

Location Code 

Life 

History 

Stage 

Sex 

How 

Detected 

Observer(s) 

Number 

McGinlam 

24/03/2003 1 ILUMBA ADULT OBSERVED 1 M. & D. 

McGinlam 

18/01/2004 28 ILUMBA ADULT F CAPTURED 1 A. Mucci 

P. Shelley 

08/02/2004 28 ILUMBA ADULT F CAPTURED 1 A. Mucci 

P. Shelley 

?? ?? ADULT M CALLING ?? M. 

Bannerman; 

R. 

Wellington 

?? ?? ADULT M OBSERVED ?? M. 

Bannerman; 

R. 

Wellington 

Table A3-4: 

Records of frog species other than the Green and Golden Bell Frog at 

Davistown since 1998 

Species Date Location Lifestage How detected Observer(s) 

Bleating 13/10/1998 30 MAGNOLIA ADULT OBSERVED G. Pyke 

Tree Frog 

Bleating 

Tree Frog 


WETLAND 

ADULT CALLING G. Pyke; 

M. Bannerman 

Common 04/06/1998 MAGNOLIA ADULT CALLING G. Pyke 

Eastern 

Froglet 

WETLAND 

Green 13/10/1998 30 MAGNOLIA ADULT OBSERVED G. Pyke 

Tree Frog 

Striped 

Marsh 

Frog 

Striped 

Marsh 

Frog 

Striped 

Marsh 

Frog 

13/10/1998 30 MAGNOLIA ADULT OBSERVED; 

CAPTURED 

G. Pyke 

02/04/2003 1 ILUMBA ADULT OBSERVED G. Pyke; 

A. Mucci 

02/04/2003 ILUMBA 

WETLAND 

ADULT CALLING G. Pyke; 

A. Mucci 

Peron’s 30/10/1998 30 MAGNOLIA ADULT OBSERVED G. Pyke 




Appendix 4: 

Davistown 

Monitoring Program at North Avoca and 

Any monitoring of frog populations must be supervised and/or carried out by appropriate 

personnel with the necessary authorities and approvals, and using approved methods. 

These methods must, in particular, be consistent with the procedures and protocols 

required by the Department of Environment and Conservation to minimize the likelihood 

that they will result in the spread of frog disease (NSW NPWS 2002). Personnel could be 

staff from a variety of institutio ns including the Australian Museum, Gosford City 

Council, Department of Environment and Conservation, and Australian Reptile Park, or 

could be freelance environmental consultants. Necessary approvals will include a 

Scientific Licence issued by DEC as well as an Animal Research Authority issued by the 

appropriate Animal Care and Ethics Committee. All staff and volunteers who participate 

in the surveys need to be aware of the licencing requirements and be familiar with the 

Frog Hygiene Protocol No 6 (Appendix 6). 

Only by monitoring the populations at North Avoca and Davistown and their habitats at 

the two sites, and by considering the interactions between populations and habitats, can 

long-term protection and recovery of these populations be reasonably likely to occur. 

Otherwise future declines in these populations may go unnoticed and, even if detected, 

the underlying causes may be unknown. 

A monitoring strategy for the Green and Golden Bell Frog may include one or more of 

the following components: 

q 

q 

q 

q 

q 

Daytime surveys of aquatic habitat, various water parameters, eggs, tadpoles and 

fish; 

Daytime surveys of terrestrial habitats; 

Night-time surveys that focus on calling male frogs, but may include frogs that 

are observed as well; 

Night-time surveys that include the capture and examination of frogs as well as 

recording frogs that are heard or seen, and may include marking individual frogs 

with subsequent capture/recapture analyses. 

Opportunistic observations 

The daytime surveys are essential. The general nature of aquatic and terrestrial habitats 

do not change rapidly or frequently, and are reasonably easy to assess. Important water 

parameters such as water temperature and salinity, which significantly affect frog 

breeding, are quick and easy to measure with appropriate technology. Is also reasonably 

quick and easy to determine the presence and density of Gambusia. Quantitative 

estimates of the densities of eggs or tadpoles provide measures of both successful 

reproduction and adult numbers. These surveys should therefore permit consideration of 

any interactions between frog numbers and the habitats. 

However, these daytime surveys require appropriate expertise and technology. 

Identification of tadpoles and fish requires training and practice. Water meters, such as 




the one we use, which is made by Yeo-kal, quickly provide estimates of a variety of 

water parameters including water temperature and salinity. The method used for catching 

tadpoles and fish should be standardized, so that it may be repeated and may provide a 

measure of sampling effort (e.g. volume of water sampled). The potential for members of 

the general community to be involved with these surveys is therefore extremely limited. 

Night-time surveys of calling frogs are not essential, but are extremely useful. They 

provide important information in relation to the abundance and breeding activity of adult 

frogs. Most importantly, they also provide a means by which the local community can 

become increasingly aware of these frogs and participate in monitoring and managing 

them. Such surveys should obviously be restricted to known or potential breeding habitat. 

Capturing and examining frogs may provide additional useful information with regard to 

the sex, age and general health of individual frogs, and are only essential if estimates of 

population size are required. 

Opportunistic observations are also potentially very useful, especially as they may 

provide information in relation to events that are infrequent and unpredictable such as 

periods of high rainfall. Such observations may include calling frogs or visible sightings, 

but may require verification if made by members of the general community. Through 

participation in frog surveys, members of the general community may learn how to 

identify frogs from sight or sound. Tape recording of frog calls may also facilitate 

identity verification when they are listened to by a person with appropriate expertise. 

Because it takes tadpoles of the Green and Golden Bell Frog about two to three months to 

complete development from egg to metamorphosis, the interval between surveys should 

not exceed eight weeks. Because of the time and costs involved, it will probably be 

impossible for the survey to be carried out much more often than this. An interval 

between surveys of six to eight weeks therefore seems appropriate. 

Because calling, eggs and tadpoles of the Green and Golden Bell Frog are unlikely, 

except during the warmer months of the year (i.e. about October to March), the surveys 

should be restricted to this period. At intervals of six to eight weeks, this would lead to 

about four surveys per year. 

We recommend that future monitoring of the frog populations at North Avoca and 

Davistown be based primarily on daytime surveys, as described above, and night-time 

surveys of calling frogs, and that these surveys be carried out about four times per year at 

intervals of six to eight weeks during the period from about October to March. We 

recommend, in addition, that allowance be made for two to three opportunistic surveys to 

be carried out per year during or after rainfall, and that members of the local community 

be encouraged to contribute their own opportunistic observations. 




Appendix 5 

Bushland Plan of Management 


North Avoca 


This Bus hland Plan of Management (BPOM) has been developed for Gosford City 

Council as part of the long-term management of Green and Golden Bell Frogs. At North 

Avoca, these frogs occur in a few places around Avoca Lagoon (Figure 5, POM) but the 

Bareena Wetland and nearby areas are regarded as core habitat for this population (see 

4.2). At Davistown, frog records are limited to a few locations in the Ilumba and 

Romford Wetlands (Figure 6, POM) and urban sites nearby. Many of the areas where the 

frogs occur are on Council owned and managed land. 

Each of the Bell Frog areas have been visited and assessed to determine whether bush 

regeneration or habitat management works are required. The assessment and condition of 

each area is presented in Table 1 below: 

Table 1 

Assessment of Bell Frog Locations 

At North Avoca and Davistown 

Location 

Bareena 

Wetland and 

Nature Strip 

Description 

Of 

Site 

Ephemeral freshwater wetland 

with tall emergent reeds and 

rushes. Nearby Swamp Oak 

Forest and Paperbark 

Woodland. Nature strip is a 

mowed area between lagoon 

and houses that is often used 

by pedestrians and people 

walking dogs. Lagoon 

foreshore in this area lined 

with tall rushes and is intact. 

Assessment 

Bareena Wetland vegetation 

intact. Nature strip contains 

exotic weeds and other 

plants that detract from its 

habitat value. Pedestrian 

impacts, as well as dog 

faeces and litter and 

dumping problems. Lagoon 

foreshore vegetation being 

mowed into and exotic 

garden plants established. 

Habitat 

Management 

Required 

No works in Bareena 

Wetland. Nature strip 

requires detailed 

regeneration work 

including rationalization 

of walking tracks, litter 

and rubbish control, 

weeding and habitat 

enhancement. Lagoon 

foreshore need 

demarcating and 

foreshore vegetation strip 

protected. 

High priority area. 




Creek and 

lagoon 

foreshore at 

northern end 

of Avoca 

Lagoon, off 

Lakeshore 

Drive. 

Western 

foreshore of 

Avoca 

Lagoon, 

southern end 

of Lakeshore 

Drive 

Southern 

fores hore area 

of Avoca 

Lagoon, off 

the Round 

Drive 

Ilumba 


Davistown 

Romford 


Davistown 

Unsealed 

gutters and 

nature strips 

Magnolia 

Avenue 

Davistown 

Creek carried urban 

stormwater. Water quality 

variable but adequate for Bell 

Frogs. Some weed growth 

along creek. Foreshore area 

lined with tall rushes. 

Eastern facing slope to lagoon. 

Tall rushes along lagoon 

foreshore, disturbed woodland 

closer to Lakeshore Drive. 

Southern bay of Avoca 

Lagoon. Some tall rushes 

along foreshore, forest and 

woodland nearby contains 

ground weeds. 

Mown easement along western 

side, creek and Swamp Oak 

and Paperbark Forest in centre 

and east. Small areas of 

Coastal Saltmarsh. Small 

forest easement across to 

Ilumba Avenue. 

Large Swamp Oak Forest and 

Paperbark swamp. Small areas 

of saltmarsh in northern end. 

Unsealed gutters on Magnolia 

Avenue used as breeding sites 

by Bell Frogs. Nature strips 

mostly mown lawn. 

Creek and foreshore 

contains shelter habitat only 

(no breeding sites). 

Shelter habitat provided by 

tall rushes along foreshore. 

Minor weed growth in area. 

Shelter habitat provided by 

rushes and ground cover 

plants. Area not thought to 

not be used often by Bell 

Frogs and of low priority. 

Mown area good location 

for Bell Frog breeding 

ponds. Swamp Oak Forest 

and associated wetland 

relatively intact. Small 

forest easement probable 

Bell Frog movement 

corridor. 

Edges of wetland subject to 

weed invasion. 

Gutters provide unreliable 

breeding sites but should be 

retained (not sealed or 

curbed). Needs some shelter 

plants nearby. 

Weed control in lower 

creek area consisting of 

manual removal of 

weeds on an occasional 

basis. 

Foreshore area intact. 

Occasional weed 

removal required in 

higher (northern) area. 

No works recommended 

for this area. 

Mown area to be retained 

as mown area (with 

breeding ponds to be 

installed). Some selective 

planting of Lomandra 

around rock piles near 

ponds. No works 

suggested for remainder 

of wetland. Small forest 

easement to be 

maintained; blackberry, 5 

leaved morning glory 

and other invasive weeds 

to be controlled. 

Routine weed control 

around edges of wetland. 

Gutters to be retained 

unsealed; low vegetation 

cover to be established 

within them. Lomandra 

could be established on 

nature strip in front of 

no. 14,16,18, 21,23 and 

25 Magnolia Avenue. 

Bareena Wetland and the nature strip and nearby lagoon foreshore represent the sites that 

require the greatest management because of their high public use, importance as core 

habitat for the North Avoca Bell Frogs and range of impacts associated with the opening 

and closing of the lagoon, weed invasion, rubbish dumping and other factors. 

Consequently, this Bush Regeneration Plan focuses primarily on providing a strategy for 

the restoration of the vegetation in and around the Bareena Wetland and nearby parts of 

the lagoon foreshore while maintaining viable habitat areas for the Green and Golden 




Bell Frogs. Other areas where Bell Frogs have been recorded do not currently require 

regeneration or landscape works and so these have been excluded from this Plan. The 

main considerations in this Plan are: 

1. management of native vegetation 

2. weed removal or control 

3. revegetation in selected areas to provide additional habitat for Green and Golden 

Bell Frogs 

4. public access 

5. monitoring and reporting. 

6. involvement of community groups 

2.0 Aims and Objectives 

The primary aim of the Bush Regeneration Plan is to provide a practical strategy that can 

implemented to restore as fully as possible the natural vegetation of the Bareena wetland 

and nearby lagoon foreshores areas while maintaining habitat for the Green and Golden 

Bell Frog. The Plan incorporates long-term weed management strategies and encourages 

natural regeneration of native vegetation. The planting of native vegetation is only 

proposed where there is a need to quickly create habitat for the frogs or native seed stock 

is absent from the site. 

Weed control methods on this site are restricted by the requirement to minimize the use 

of herbicides in the wetland (because of potential adverse effects on the resident Bell 

Frogs and other aquatic organisms). 

Bush regeneration around the wetland will be staged to ensure tha t habitat for the Green 

and Golden Bell Frogs is already established before old habitat areas are disturbed. 

Bush regenerators (and other workers on the sites) must be aware that Green and Golden 

Bell Frogs are a threatened species and are listed under sections of Federal and State 

Government environment legislation. Bell Frogs can only be handled by persons licenced 

by the Department of Conservation and Environment and all proposed works in Bell Frog 

habitat areas must conform with this legislation (see also Section 7.2). 




3.0 Description of Bareena Wetland Site 

The Bareena Wetland site is an artificial wetland on the northern side of Avoca Lagoon 

(Figures 1 and 2). The wetland was created when earthen levees were installed around a 

small area of the lagoon foreshore. The area within the levees was not in-filled and the 

levees have acted as a “slow dam” that retards the flow of stormwater across the site into 

the lagoon. The levees do not prevent saline water from Avoca Lagoon from seeping 

through into the wetland. Despite the presence of the levees, the height of water in the 

wetland is still strongly related to the water level in the lagoon. When the lagoon is low, 

the wetland is also low and often highly saline; when the lagoon is higher, the wetland is 

higher but contains freshwater and brackish areas. 

The area inside of the levees is about 2 Ha but the area of water in the wetland varies 

considerably from zero during drought periods to a maximum of 1.4 Ha during periods of 

sustained rainfall and high water levels in the lagoon. The majority of the wetland 

comprises reed beds, mainly of the Common Rush Phragmites australis or Marsh 

Clubrush Bolboschoenus caldwelli (Figure 2). The levees are dominated by Swamp Oak 

Casuarina glauca, the understorey consists of a mixture of exotic shrubs and grasses; 

Bitou Bush* Chrysanthemoides monilifera, Lantana* Lantana camara, Morning Glory* 

Ipomoea indica and Asparagus Fern* Protasparagus aethiopicus are the dominant shrubs 

with Mat Rush Lomandra longifolia present in isolated clumps around the wetland. 

* indicates exotic species. 

The northern end of the wetland is dominated by Broad-leaved Paperbarks Melaleuca 

quinquenervia and these trees are also present in the grasses areas around the eastern side 

of the lagoon. The central part of the lagoon is dominated by tall reeds, especially the 

Marsh Clubrush Bolboschoenus caldwelli and the Common Rush Phragmites australis. 

The wetland is surrounded on its northern and eastern sides by a mowed area that 

contains a sewer easement and public walking track. 

The southern portion of the wetland is subject to strong southerly winds and this has 

damaged or stunted the She-oak Trees along the lagoon shoreline. Clumps of Coastal 

Daisy Melanthera biflora are present on the sandy sites while Pennywort Hydrocotyle 

bonariensis * (this is an introduced species) forms the most common other type of ground 

cover. Behind the front line of stunted She-oaks exotic grasses and weeds replace the 

native ground cover plants. 

For the purpose of the Bush Regeneration Plan, the wetland has been divided into two 

zones (Figure A5-2); Zone 1 comprises the southern and western levees embankments 

and edges of the wetland; Zone 2 comprises the northern and eastern margins of the 

wetlands. The two zones have been recognized as they have different vegetation 

structures and are subject to different impacts. Zone 1 abuts the lagoon, is dominated by 

Casuarina forest (Swamp Oak Forest, Figure A5-1) and has a weedy understorey; Zone 2 

does not abut the lagoon, is dominated by Paperbarks (Figure A5-3) and is an area that is 

subject to pedestrian traffic and regular mowing. 




Figure A5-1 

Vegetation Zones at Bareena Wetland 




Figure A5-2 

Western Bank of Bareena Wetland 

Figure A5-3 

Paperbark Forest, Bareena Wetland 




4.0 Frog Habitat in the Bareena Wetland 

The use of the Bareena Wetland by Green and Golden Bell Frogs Litoria aurea has been 

under study by Dr Graham Pyke of the Australian Museum and volunteers for five years. 

The data from this study is summarized in the Plan of Management for Avoca Lagoon 

and Davistown (Section 5.1). In general, Bell Frogs use areas around Bareena Wetland 

and along the lagoon margins as foraging and shelter areas. The frogs also forage in the 

yards of nearby residences. 

Breeding occurs in Bareena Wetland but is problematic for the frogs. The salinity levels 

of the wetland are often too high to permit breeding or the survival of the tadpoles. After 

local rain, some areas of relatively freshwater are created in the wetland and the Bell 

Frogs may spawn in these; the survival of the tadpoles appears to depend on how long the 

freshwater pockets remain. 

For Bell Frogs, four important habitat components must be present if the frogs are to 

survive in an area in the long-term (Pyke and White 2001): 

1. Secure breeding habitat: breeding habitats must not only provide sites for 

spawning but also persist long enough for the tadpoles to metamorphose and 

disperse. 

2. Foraging habitat: areas where adult and juvenile Bell Frogs can feed safely must 

exist. Bell Frogs eat a wide range of vertebrate and invertebrate prey items, but 

most often forage around the edges of standing water or in grassy verges. 

3. Diurnal shelter habitats: bell frogs require refuge areas during their active times of 

the year. In the spring and summer, in particular, Bell Frogs require refuge areas 

during the day where they can bask and still be relatively safe from attack by 

birds or snakes. Bell Frogs typically use tall emergent reeds in ponds (such as 

bulrushes Typha orientalis, Spike Rushes Eleocharis sphacelata) or tussockbased 

plants near ponds such as Mat Rush Lomandra longifolia, Saw-sedge 

Gahnia sp. , Pampas Grass* or Swamp Lily Crinum pedunculatum as diurnal 

shelter sites. 

4. Over-winter habitat: during periods of prolonged dry or cold weather Bell Frogs 

will become inactive and shelter under a variety of substrates. In the warmer 

months, they may shelter in the mud at the base of drying ponds; in the colder 

months they shelter under rocks, logs or inside dense mats of low vegetation. 

These areas provide a cool, damp and disturbance-free environment for the 

inactive frogs. 

Breeding Habitat: 

Breeding habitat is confined to the Bareena Wetland and freshwater ponds do not 

accumulate in other areas nearby. The main area of the wetland contains beds of reeds 

and sedges; at present there are no exotic plants that need to be controlled there. Breeding 

habitat for Green and Golden Bell Frogs is unlikely to be enhanced through changes to 




the vegetation in the wetland as the availability of freshwater in the wetland appears to be 

the main limiting factor for breeding opportunities for this species. 

Foraging Habitat: 

Foraging habitat is more widespread and diverse in nature; it includes the sedges and 

grasses that bound the wetland as well as grassed and sedge areas within 200 meters of 

the wetland (including the nature strip to the west of the wetland). Foraging habitat may 

also extend into the backyards of some nearby residences. Most of the foraging habitat at 

present appears to be provided by exotic grasses that occur along the levees banks and 

surrounding margins of the wetland. While these grasses are exotic and have in places 

overrun native ground covers, their role as foraging habitat for Bell Frogs means that 

their possible remo val and replacement with other forms of vegetation needs to be treated 

with great caution. 

At present, it appears that the retention of kikuyu grass along the levee banks and nearby 

areas may be the best option as there is no native ground cover that can provide the same 

habitat value. In addition, the kikuyu is somewhat contained by the salinity of the ground 

and ground water and over-shadowing by the tree canopy. Other grasses, such as Buffalo 

Grass and Coastal Couch, do not appear to thrive as well at Bareena Wetland and are not 

a threat to the ecosystem. Kikuyu is a vigorous growing grass and could become a threat 

to other ground cover plants, however, its domination of the understorey is being 

naturally retarded by the salinity of the surrounding soil. 

Overall, it seems safest to retain the kikuyu in certain areas where it can grow long 

without encroaching into other parts of the wetland. In areas close to the wetland where 

the kikuyu is regularly mowed, it no longer has habitat value. The proximity of mowing 

to the wetlands needs to be assessed and un-mown areas demarcated so that they cannot 

be accidentally cleared and frog habitat destroyed. 

Diurnal Shelter Sites: 

Diurnal shelter sites occur both within and around the wetland. At present, about half of 

the area of the wetland is dominated by tall emergent reeds (see POM Figure 2). These 

plants appear to provide adequate cover within the wetland. Outside of the wetland, 

diurnal shelter sites are more limited. Some clumps of Mat Rush are present around the 

wetland but some of these have become overgrown by weeds such as Asparagus Fern, 

Morning Glory and Turkey Rhubarb. While clumps of dense vegetation are desirable 

around the wetland, these invasive weeds prevent the native tussock plants from 

spreading and becoming larger and of greater shelter value. 

Selective clearing of invasive ground cover plants around the wetland appears to be 

required to help protect frog habitat as well as prevent any further spread of unwanted 

exotic plants. 




Over-winter Sites: 

The location of over-winter sites at North Avoca have not been determined as yet. It 

appears that Bell Frogs are unable to over-winter in the wetland because of the high 

salinity levels in the mud and deeper water in the wetland. This means that all overwintering 

must occur away from the wetland. There are no rocks or logs near the wetland 

that could be used as over-winter habitat (although recently created wood heaps could 

serve this purpose). It is most likely that over-wintering occurs in some of the tussock 

plants around the wetlands and in the backyards of nearby residences. 

The retention of dense clumps of tussock plants around the wetlands is important for the 

survival of the frogs. Given the extent of cover by exotic grasses it is unlikely that dense 

clumps of Mat Rush or other tussock plants will establish naturally, even with the 

removal of exotic vegetation. The density of tussock plants can be quickly increased by 

direct planting of Mat Rush, Swamp Lily and native tussock grasses around the site. All 

plants that are to be established must be of local provenance. 

5.0 Description of Zone 1 

Zone 1 consists of a narrow, raised earthen levee that extends around the southern and 

western margin of the wetland. The majority of the zone is covered by Casuarina glauca 

forest. Swamp Oak Forest has recently been recognized as an endangered ecological 

community under Schedule 1 Part 3 of the New South Wales’ Threatened Species 

Conservation Act 1995. This means that native plant species that form part of this 

endangered ecological community are not to be destroyed and exotic species must not be 

introduced into the area. Any works in this areas that might damage Swamp Oak Forest 

would require the consent of Gosford City Council and the Dept. of Environment and 

Conservation. 

Zone 1 is closest to the lagoon waters and is most subject to the impact of salt water and 

salt spray. The zone is also very exposed to direct wind action, particularly from the 

south and south-east. The effect of the wind is evident on the Casuarina trees at the 

southern edge of the zone where the tops of the trees have been sheared and the trees are 

leaning and stunted. Casuarina glauca has some salt tolerance and it dominance along 

this zone is due mainly to its ability to cope with saline ground water. 

An informal walking track passes through Zone 1 but this is a minor track; most of the 

pedestrian traffic uses the path on the eastern side of the wetland (in Zone 2). 

The high degree of wind exposure in Zone 1 has created bare areas that have become 

colonized by invasive salt-tolerant plants. This is the only area of the wetland where 

Bitou Bush* is found. In more sheltered areas Lantana and other invasive plants have 

become established. 

Figure A5-4 indicates the areas of greatest weed infestation in the two zones around the 

Bareena Wetland. The yellow areas are areas of medium weed infestation while the green 




areas depict light weed infestation. The trees that are numbered on the figure are trees to 

be removed: Tree 1 is a coral tree Erythrina sykesii X, Trees 2,3,4 and 5 are mulberry 

trees Morus alba, trees 6 and 7 are exotic palms Archonotphoenix sp. and Phoenix sp. 

while tree 8 is a Norfolk Island Hibiscus Lagunaria patersonia. 

Figure A5-4 

Weed Distribution and Density 





5.1 Vegetation Components of Zone 1 

Present Condition 

Resilience: Casuarina cover secure 

Original ground cover mostly lost and unlikely to 

Recover without assistance 

Disturbance: Casuarina cover intact 

Ground cover badly disturbed or absent 

Structural Diversity: Casuarina monoculture 

Weed dominated ground cover 

Habitat Value: Casuarina canopy- wind protection 

Ground cover shelter and foraging habitat 

Impacts: 

Walking track along western side 

Changing water levels in lagoon 

Zone 1 is highly exposed to strong south or south-easterly winds. These winds also 

contribute salt spray to area. 

The Casuarina tree cover has stabilized the levee banks and provides some protection for 

the wetlands from wind and salt spray. The ground cover is dominated by exotic and 

invasive plants that have some habitat value for the Bell frogs. The staged removal of 

these unwanted plants must be balanced with the creation of replacement habitat 

BEFORE the exotic vegetation is removed. 

The exotic grasses provide the greatest foraging resource for the Bell Frogs and there 

does not appear to be a suitable replacement native grass that could provide the same 

habitat value under these climatic conditions. Therefore, the priority will be towards the 

removal of invasive plants (such as Morning Glory*, Asparagus Fern*, Lantana*, Bitou 

Bush*) and their replacement with suitable native ground cover plants that can provide 

frog habitat value. 

Since the site is artificial and there does not appear to be an intrinsic source of native 

ground cover seed, the establishment of native ground cover plants will have to be 

achieved through directed planting. The diversity of ground cover pla nts will not be high 

and only five ground cover species have been chosen to be sown in Zone 1: 

Mat Rush 

Swamp Lily 

Boobialla 

Saltbush 

Native Spinach 


Crinum pedunculatum 

Myoporum bonienense 

Atriplex australasica 

Tetragonia tet ragonoides 




The lagoon front will require a different planting regime due to the strong influence of 

wind and salt spray. The chosen plants for this area are: 

Sea Grass 

Coastal Geranium 

Coastal Bearded Heath 

Pig face 

Sporobolus virginicus 

Pelargonium australe 

Leucopogon parviflorus 

Carpobrotus glaucescens 

The amount of replanting along the southern end of Zone 1 will be small and will only 

take place in areas where clumps of Bitou Bush*, Lantana* or other weeds have been 

removed and an area of bare soil exposed. If the ground cover plants are available nearby, 

they could be transplanted rather than importing plantings from elsewhere. 

It appears unlikely that the exotic grasses will overgrow native ground cover plants that 

are sown because the soil salinity and Casuarina canopy restricts the growth of many of 

the grasses (especially Kikuyu*). 

5.2 Management of Zone 1 

Timing of Works: 

Although the movements of Green and Golden Bell Frogs at North Avoca are seasonal, 

the proposed staged rehabilitation works should not adversely interfere with frog activity 

at the site during the various times of year. For this reason, the proposed bush 

regeneration and site rehabilitation works can be carried out at any time of the year. 

Order of Work: 

1. Closure and Replanting of the Western Walking Track 

The Plan of Management has recommended the closure and rehabilitation of the western 

walking track. The closure of the track may involve the erection of a “natural” barrier 

(Figure 5) to the track at the southern and northern entry points, along with the erection 

of information signs highlighting the conservation significance of this area. The walking 

path is to be replanted with clusters of 2-3 Lomandra plants, spaced at 10 metre intervals 

along the track. No trees or tall shrubs are to be planted in this area. 

If the walking track is not closed or there is likely to be as long delay before the track is 

closed, the surface of the track should be covered with a light mulch to prevent further 

erosion and that will not impede people walking on it. No mowing or using whipper 

snippers is to be carried out along this track. 




Figure 5 

Location of “No Mow”Areas and Track Signs 

2. Demarcation of No-Mow Zone 

Zone 1 extends around the foreshore of Avoca Lagoon. Over time the natural foreshore 

vegetation has been cut back to create a widened nature strip. The strip is now too wide 




and habitat for Green and Golden Bell Frogs along the lagoon foreshore is too uneven, 

and absent in places. Small wooden pegs are recommended to be placed along a line 5-7 

metres out from the lagoon shoreline and parallel with the shoreline. The pegs will 

indicate the limit of mowing for Council maintenance workers. If local residents persist 

in mowing behind the pegs, a more substantial mowing barrier may be required in those 

locations; this will be at the discretion of Council officers. 

3. Weed Removal 

Removal of Asparagus Fern*, Lantana*, Norfolk Island Hibiscus* (Tree 8 in Figure 4) 

and minor weeds from along the western berm is required. Most of these unwanted plants 

can be removed manually. The Norfolk Island Hibiscus* is best treated on site by frilling 

and poisoning the tree. There has already been a concerted effort to remove Norfolk 

Island Hibiscus* from the wetlands and only a few trees still remain along the lagoon 

foreshore. 

Particular care should be taken when removing ground cover plants as frogs may be 

sheltering in dense weed areas. If frogs are unearthed they should be released in a close 

by area where there is also dense ground cover (for protection from predatory day birds). 

If injured frogs are found, they should be placed in a sealed container (with a small 

amount of water) and transferred to the Australian Reptile Park for treatment (see 

Appendix II for contact details and handling procedures). 

Target Species for Weeding 

Species Common Name Methods 

Lagunaria patersonia Norfolk Island Hibiscus Frill LO 

Protasparagus aethiopicus Asparagus Fern HW R 

Ipomoea indica Morning Glory HW 

Lantana camara Lantana HW CP BD 

Chrysanthmoides 

Bitou Bush 

HW RF R 

monilifera 

Rumex sagittata Turkey Rhubarb HW RF 

Pennisetum clandestinium Kikuyu HW 

Stenotaphrum secundatum Buffalo Grass HW 

Conyzia sp. Fleabane HW RF 

Hypochoeris radicata Cats Ear HW RF 

Bidens pilosa Cobblers Peg HW RF 

Verbena bonariensis Purple Top HW 

Sonchus oleraceus Common Sowthistle HW 

Key to Weeding Techniques 

Code 

Explanation 




FRILL 

HW 

CP 

RF 

R 

LO 

BD 

Frilling 

Hand Weed 

Cut and Paint with herbicide 

Remove fruit, seed or flowers 

Remove from Site 

Leave on Site –in piles 

Break into small pieces 

Dead Plant Material 

Fallen or cut branches and logs are useful additions to the frog habitat around the 

wetland. Dead timber could be stacked in areas where it is not unsightly and still be close 

to the wetland. 

Weed flowers, seeds or tubers should be bagged and removed from the site. 

Mulching of Weeded Areas 

The weeded areas will be the sites for the replanting of native ground cover. In 

preparation for the arrival of tubestock, the weeded areas should be covered with a thick 

mulch to prevent weed regrowth. The mulch will have to be pulled back when native tube 

stock are planted. In addition, in areas where the mulch is likely to be washed out, low 

timber props partially buried in the soil may be needed to stabilise the surface mulch. 

Mulch that is imported onto the site must be pre-treated by exposure to direct sunlight for 

48 hours before it can be brought into the wetland. This pre-treatment will kill the spores 

of frog pathogens such as chytrid and is a requirement of the Department of Environment 

and Conservation (Frog Hygiene Protocol No. 6; Appendix 6 of POM). 

4. Replanting Strategy 

Ground Preparation 

Areas on either side of the foot track will be planted with clumps of Mat Rush and other 

ground cover plants. To facilitate the establishment of these plants, exotic grasses in the 

area will need to be killed or suppressed. The areas for the replanting can be tilled over to 

break up the grass roots and plastic sheeting or weed mats placed over the areas to kill the 

grass roots and stop weed seeds from germinating in the disturbed soil. This should be 

done at least four weeks prior to the date for planting. 

Planting 

Planting along the western side of the wetland will consist mainly of clumps of Mat Rush 

being established along the higher parts of the levee. Mat Rush should not be planted as 

individual or isolated plants but should be planted as a group of three or four plants that 

are spaced by 50 to 75 cm apart. As these plants grow, they will overlap and create a 




wide-based protective cluster. The Mat Rush will be planted in the more open areas (that 

have been cleared of weeds or grass). 

If tubestock Mat Rush is used, holes and tubestock should be watered prior to planting. 

Tubestock should be watered in after carefully planting. A regime of watering will be 

required for at least a month until they have become established. 

A light mulch should be applied around the base of the plants after planting to help retain 

ground moisture and retard invasion by exotic grasses or ground covers. 

The spacing of seedling native grasses should be at 20 cm intervals. 

5. Maintenance 

After planting and primary weeding has been completed- monthly monitoring to be done 

and maintenance of weeding as required. 

Some weeds have the potential to re-establish quickly, particularly those that may have 

seeded before removal e.g. Bitou Bush*, or those that can spread vegetatively e.g. 

Lantana*. Areas where these plants have been removed should be especially rechecked 

so that new growths can be removed early. If weeds have become established, remove the 

flowering heads or seed heads. The mass of the plant can then be removed at a more 

convenient time. 

The most problematic weeding issue is likely to be the continued invasion of newly 

planted areas by exotic grasses. A grass-free area will have to be maintained around the 

new plantings. Spraying of the grass around the new plantings will be required (taking 

care to shield the young plantings while spraying is underway). Round-up Bioactive 

should be used as this is the least problematic herbicide for frogs. Weed mats or plastic 

sheeting may be used to control any further spread of the grasses. Take care not to 

smother or disturb the newly planted native species. 

5.3 Suggested Time Frame of Works 

The following time frame lists the proposed works, their order of completion and a 

suggested time for the start of each activity. 

Action Date Start Date Finish 

Closure and May 2006 December 2006. 

replanting of 

Western Walking 

Track 

Demarcation of “No 

Mow: Area 

Meeting with 

residents first half of 

2006 

Placement of pegs 

or barriers by June 

June 2006 2006 




or barriers by June 

2006 

Tree Removal June 2006 December 2006. 

Weed removal Areas staggered July 2007 

North-western side 

of wetland: April – 

July 2006 

Central Western 

Section: August – 

November 2006 

South-western 

section December 

2006-February 

2007. 

Lagoon foreshore 

areas: March 2007 

Mulching 

North-western area February 2007 

July 2006 

Central western: 

November 2006. 

South-western: 

February 2007. 

Replanting North-western area February 2007 

July 2006 

Central western: 


South-western: 


Maintenance Monthly following On going 

completion of an 

area. 

Maintenance of 

Nature Strip 

As required On going 




6.0 Description of Zone 2 

Zone 2 probably represents the original boundary of Avoca Lagoon. Unfortunately, it is 

also that most disturbed zone around the wetland. Houses have been established backing 

onto Zone 2 along the northern and eastern side of the wetland. A conseque nce of the 

development of the residential area has been an encroachment of mown lawns, extended 

gardens and walking areas. Native ground covers have been almost totally removed from 

this area and been replaced by exotic lawns or exotic garden plants. The dumping of 

garden clippings, tree prunings or other garden waste has occurred in Zone 2 and has 

resulted in a further spread of garden plants in Zone 2 and the wetland. Low-lying areas 

around the wetland in Zone 2 have been filled in to create an even surface. Zone 2 

includes the nature strip that runs to the west of the wetland, between the lagoon 

shoreline and the residences facing Lake Street. 

The dominant tree cover in Zone 2 is the Broad-leaved Paperbark Melaleuca 

quinquenervia. These trees still preva il along the northern edge of Zone 2 but have been 

more disrupted along the eastern portion of Zone 2. In recent year, residents have planted 

exotic trees to replace dead or unwanted paperbark trees in Zone 2. Exotic palm trees and 

Norfolk Island Pines have been planted along the eastern area while Mulberry Trees and 

Coral Trees have become established along the northern area. 

The ground cover in Zone 2 consists mainly of mown Kikuyu* and Buffalo Grass* lawn. 

Thickets of garden weeds have become established around the base of paperbark trees or 

stumps. Some weeds have penetrated the margins of the wetland. 

An informal car turning area has been created on the eastern side. 

Unlike Zone 1, wind exposure and salt spray is not a major limiting factor in the survival 

of plant species in the area. The Casuarina cover along the southern side of the wetland 

and the houses along the eastern side of the wetland have shielded the site from most of 

the prevailing wind. 

A regularly used informal walkway exists through Zone 2. 




6.1 Vegetation Components of Zone 2 

Present Condition 

Resilience: Melaleuca cover intact along northern side, gaps in 

Canopy along eastern side. 

Original ground cover mostly lost and unlikely to 

Recover without assistance 

Disturbance: Melaleuca cover intact 

Ground cover badly disturbed or absent. Exotic 

Grasses and garden weed dominating the ground cover. 

Dumping of garden wastes. 

Regular mowing of Zone 2 

Structural Diversity: Melaleuca tree monoculture 

Weed dominated ground cover 

Habitat Value: Melaleuca canopy used by birds 

Limited ground cover shelter and foraging habitat for 

frogs 

Impacts: 

Walking track along northern and eastern side 

Dumping of garden wastes 

Mowing up to edge of wetland in places 

Zone 2 is less subject to natural disturbances of wind and sea spray but is much more 

prone to human-based impacts. The presence of the houses next to Zone 2 and the 

walking track within the zone, means that there is a continual disturbance to the 

vegetation. While the existing cover of paperbark trees is relatively intact, there is little 

scope for replacement of the paperbark trees naturally. Regular mowing of Zone 2 

prevents the establishment of young seedlings and promotes the cover of exotic grasses in 

the area. Replacement of paperbark trees in Zone 2 is not warranted at present but in the 

future seedlings will have to be planted and protected during their early growing stages. 

Several exotic trees have been planted in Zone 2 and some of these are not wanted, 

especially the Mulberry Trees. It is recommended that these trees be poisoned and 

eventually replaced with paperbark tree s. 

Residents backing onto Zone 2 also need to be made aware that Zone 2 is not an 

extension of their property. The deliberate planting of exotic trees (such as palms) should 

be discouraged, and if negotiations with the residents are productive, removed and 

replaced with native trees. Residents also need to be made aware that dumping of garden 

wastes in the wetland and in Zone 2 is destructive to the habitat and this practice should 




cease despite the fact that Bell Frogs may occasionally use wastes heaps as shelter or 

overwinter sites. 

The ground cover in Zone 2 is almost completely exotic. The exotic grasses in this area 

provide little habitat for Bell Frogs as it is regularly mowed. The only shelter habitat for 

the frogs in this area comes from garden plants that exist around the bases of trees in this 

zone. 

The priority for Zone 2 will be the demarcation of mowed areas and the restoration of 

native ground cover in the areas that are not to be mowed. It is recommended that nonoffensive 

barriers be set in place around the wetland to prevent accidental encroachment 

by the lawn mowers into frog habitat areas. Low timber barriers or obstructive marker 

poles could be set around the wetland; these types of barriers are quickly concealed by 

the taller sedges and reeds and are not readily visible to the passer-by. However, the 

presence of solid timber posts prevents mowing in these areas as well as restricting 

pedestrian access. 

Most of the exotic ground cover and grasses can be removed manually but the 

replacement ground cover will need to be planted form local provenance seed-stock. The 

main ground covers that are to be planted are: 

Sea Rush 

Coastal Fescue 

Coastal Tussock Grass 

Sea Grass 

Juncus kraussi 

Austrofestuca littoralis 

Poa poiformis 

Sporobolus virginicus 

Clumps of Mat Rush should also be planted against the bases of trees to replace garden 

plants in these locations. 

Mat Rush 


What about the following?? 

Swamp Lily Crinum pedunculatum 

Native Spinach Tetragonia tetragonoides 

Dianella - Dianella caerulea var. producta 

6.2 Management of Zone 2 

Timing of Works 

As for Zone 1, the timing of works will not be a significant limitation of Bell Frogs 

movements or activity. Bush regeneration works can take place at any time throughout 

the year. 

Order of Work: 




1. Demarcation of Mowed Areas 

A meeting with Gosford City Council should take place to determine the location of 

boundary markers and barriers. Sufficient space needs to be provided for the walking 

track and some landscaping near the residences. Areas between the walking track and the 

wetland need to be agreed upon and protected. In general, the no-mow areas need to 

create a strip of taller ground cover vegetation about 5 metres wide along the eastern edge 

of the Bareena Wetland. The meeting will also need to determine what type of barriers 

would be most suitable for the site and where they should be placed. Ideally, the marker 

pegs should be small and inoffensive, but still clearly define the no mow boundary to 

Council maintenance staff. 

Once the non-mowed areas have been decided, the task of removing the unwanted ground 

cover plants and replacing them with appropriate native ground cover species can be 

begin. 

At present, a number of residents mow sections of the nature strip behind their houses 

and the non-mowing areas need to be made obvious to these people as well as Council 

workers. 

2. Tree Removal 

Discussions with local residents should be initiated to explain why trees such as the 

Mulberry Trees and exotic Palms are unsuitable for the area and should be removed. 

Once agreement has been reached, the trees can be poisoned and replaced with seedling 

paperbark trees or other native species (e.g. Swamp Mahogany Eucalyptus robustus, 

Bangalay Eucalyptus botryoides) if necessary. Trees 1-7 (Figure 4) should be removed. 

However, it must be noted that the nature strip must not be densely replanted with trees 

and become a woodland corridor; the area north of the Bareena Wetland needs to be kept 

relatively open so that there is sufficient direct sunlight on the Bell Frog basking areas in 

the Bareena Wetland. If the planting of a tree is likely to result in shade on the wetland, 

the tree should not be planted. 

3. Weed Removal 

The removal of Asparagus Fern*, Spider Plant*, exotic grasses and garden plants from 

areas inside of the demarcated area is recommended. These unwanted plants can be 

removed manually. 

As for Zone 1, particular care should be taken when removing ground cover plants as 

frogs may be sheltering in dense weed areas. If frogs are unearthed they should be 

released in a close by area where there is also dense ground cover (for protection from 

predatory day birds). If injured frogs are found, they should be placed in a sealed 

container (with a small amount of water) and transferred to the Australian Reptile Park 

for treatment (see Section 8.0 for contact details and handling procedures). 




Target Species for Weeding 

Species Common Name Methods 

Morus nigra Mulberry Tree CP LO 

Phoenix sp and 

Exotic Palm Trees 

CP LO 

Archaeontophoenix sp. 

Protasparagus aethiopicus Asparagus Fern HW R 

Chlorophytum comosum Spider Plant HW 

Chenopoudium album Fat Hen HW BD 

Ipomoea indica Morning Glory HW R 

Rumex sagittata Turkey Rhubarb HW R 

Pennisetum clandestinium Kikuyu HW 

Stenotaphrum secundatum Buffalo Grass HW 

Conyzia sp. Fleabane HW RF 

Plantago lanceolata Lamb’s Tongue HW RF 

Bidens pilosa Cobblers Peg HW RF 

Verbena bonariensis Purple Top HW 

Sonchus oleraceus Common Sowthistle HW 

Key to Weeding Techniques 

Code 

HW 

CP 

RF 

R 

LO 

BD 

Explanation 

Hand Weed 

Cut and Paint with herbicide 

Remove fruit, seed or flowers 

Remove from Site 

Leave on Site –in piles 

Break into small pieces 

Dead Plant Material 

Fallen or cut branches and logs are useful additions to the frog habitat around the 

wetland. Dead timber could be stacked in areas where it is not unsightly and still be close 

to the wetland. 

Weed flowers, seeds or tubers should be bagged and removed from the site. 

Mulching of Weeded Areas 

The weeded areas will be the sites for the replanting of native ground cover. In 

preparation for the arrival of tubestock, the weeded areas should be covered with a light 

mulch or plastic sheeting. If plastic sheeting is used, an explanation sign should be placed 

near the work area to try to avoid the unwanted removal of the plastic by well-intentioned 

passers-by. Plastic sheeting is preferred in thickly grassed areas, as it will retard the 

spread of exotic grasses. If mulch is imported onto the site, it must be pre-exposed to 




direct sunlight for 48 hours before brought onto the site; this pre-treatment will kill the 

spores of frog pathogens such as chytrid. 

4. Replanting Strategy 

Ground Preparation 

Areas inside of the mowing barrier will be planted with clumps of Mat Rush and other 

ground cover plants. To facilitate the establishment of these plants, exotic grasses in the 

area will need to be killed or suppressed. The areas for the replanting can be tilled over to 

break up the grass roots and plastic sheeting or weed mats placed over the areas to kill the 

grass roots and stop weed seeds from germinating in the disturbed soil. This should be 

done at least four weeks prior to the date for planting. 

Planting 

Planting along the northern side of the wetland will consist mainly of clumps of Mat 

Rush and some native grasses. Mat Rush should not be planted as individual or isolated 

plants but should be planted as a group of three or four plants that are spaced by 50 to 75 

cm apart. As these plants grow, they will overlap and create a wide-based protective 

cluster. The Mat Rush will be planted in the more open areas (that have been cleared of 

weeds or grass). 

If tubestock Mat Rush is used, holes and tubestock should be watered prior to planting. 

Tubestock should be watered in after carefully planting. A regime of watering will be 

required for at least a month until they have become established. If ground cover plants 

are available from nearby they could be transplanted into the prepared sites, rather than 

importing new plants from outside. 

A light mulch should be applied around the base of the plants after planting to help retain 

ground moisture and retard invasion by exotic grasses or ground covers. 

Native grasses should be planted at 20 cm spacing. 

5. Maintenance 

After planting and primary weeding has been completed- monthly monitoring to be done 

and maintenance of weeding as required. 

Some weeds have the potential to re-establish quickly, particularly those that may have 

seeded before removal e.g. Cobbler’s Peg*, or those that can spread vegetatively e.g. 

Lantana*. Areas where these plants have been removed should be specially rechecked so 

that new growths can be removed early. 

If weeds have become established, remove the flowering heads or seed heads. The mass 

of the plant can then be removed at a more convenient time. 




As for Zone 1, the most problematic weeding issue is likely to be the continued invasion 

of newly planted areas by exotic grasses. A grass-free area will have to be maintained 

around the new plantings; this will involve spading an area around the plantings to cut off 

any sub-terranean roots or shoots. The surface soil can be lightly turned and weed mats or 

plastic sheeting used to control any further spread of the grasses. Take care not to disturb 

the newly planted native species. 

Maintenance of Nature Strip 

The grassed areas outside of the demarcated frog habitat areas will need periodic mowing 

and general maintenance. As Bell Frogs may venture into the nature strip to feed, some 

precautions are advised before mowers and whipper snippers are used. Areas of long 

grass will need to be disturbed to see if frogs are concealed within. This usually means 

walking through the grass looking for signs of frog activity in it or brushing a gloved 

hand through the tussocks to try to disturb frogs and force them to hop. If frogs are 

disturbed, they should be caught and released in the wetland, away from the area of 

mowing. If regular mowing is carried out in the nature strip, flushing of frogs from the 

grass sho uld only be necessary along the edges of the no-mowing area. 

Maintenance of the nature strip will normally consist of periodic mowing of the public 

walking areas, trimming around tall shrubs and hand removal of occasional weeds. 

The main public walking track alongside the Bareena Wetland is on the eastern side, it 

may be necessary at times to treat erosion areas along the path. At present the main area 

of erosion and surface plant loss is at the south-eastern corner of wetland where the track 

reaches the lagoon sand. This section may require protection in the form of sand 

stablising and replanting of spinifex or a tough sand-binding grass. Further along the 

track where bare areas have been created by human traffic, mulch can be spread over the 

bare sand to help prevent weed establishment. 

6.3 Suggested Time Frame of Works 

The following time frame lists the proposed works, their order of completion and a 

suggested time for the start of each activity. (see previous changes, this needs revision 

given delays in finalizing the POM, it still needs to be reported to Council for 

recommended adoption). 

Action Date Start Date Finish 

Demarcation of “No Meeting with April 2006 

Mow: Area residents early 2006 

Emplacement of 

pegs or barriers 

April 2006 

Tree Removal March 2006 December 2006. 

Weed removal Areas staggered 

Northern side of 

wetland: April – 

February 2007 




Mulching 

Replanting 

Maintenance 

Maintenance of 

Nature Strip 

wetland: April – 

July 2006 

Central Eastern 

Section: August – 

November 2006 

Southern section 

December 2006- 


Northern area July 

2006 

Central eastern: 


Southern: February 

2007. 

Northern area July 

2006 

Central eastern: 


Southern: February 

2007. 

Monthly following 

completion of an 

area. 

As required 

February 2007 

February 2007 

On going 

On going 




7.0 Green and Golden Bell Frog Safety Procedures for Volunteer 

Bush Regenerators 

During your work at Bareena Wetland you may encounter frogs. Unfortunately, several 

exotic diseases have entered Australia in the last 30 years that effect frogs. Any sick frogs 

found at Bareena Wetland could be important for the survival of the whole community. 

Finding sick or dead frogs could help prevent a much larger epidemic at the wetland. 

If you find sick or dead frogs, or inadvertently injure a frog these should be reported to 

the Coordinator. Frogs that exhibit signs of Chytrid fungus may have red marks on their 

underside, be lethargic and exhibit unusual movement. IT IS EXTREMELY 

IMPORTANT THAT SICK FROGS ARE NOT MOVED TO OTHER AREAS AND 

THAT THE FUNGAL INFECTION IS NOT SPREAD TO OTHER FROGS. REFER 

TO THE HYGIENCE PROTOCOLS AT THE END OF THIS DOCUMENT FOR 

FURTHER DETAILS ON IDENTIFICATION AND HANDLING OF SICK FROGS. 

REPORTING SICK OR DEAD FROGS 

The Coordinator should report all sick frogs to the Australian Reptile Park and act on 

advice received (contact number is 4340-1022.) 

USE OF PESTICIDES and HERBICIDES 

No pesticides or herbicides are to be used in the Bareena Wetland. Although some 

formulations e.g. Bio-Active RoundUp, have been made more “frog-friendly”, they are 

still toxic to frogs and tadpoles over time. Therefore, no herbicide or pesticide should be 

used in areas where they could be accidentally washed into the wetland (either by rain 

action or through direct spraying). 

Pesticides and herbicides can be used along the nature strip. Only BioActive RoundUp 

can be used as a spray and only during dry and relatively still conditions. If it is to be 

used as a spray, the vegetation will need to be checked beforehand to ensure that frogs 

are not hiding in the vegetation. If frogs are found, licenced handlers may relocate the 

frogs to a safer area; if no licenced person is present, the frog can be encouraged to move 

to another area (by exposing the frog to direct light or gently prodding it with a blunt 

stick). If the frog won’t move, spraying or using herbicides cannot proceed there. 

Where mixed clumps of native and exotic plants occur together, the exotic species should 

be removed manually while trying not to disturb the soil around the native species (if 

possible). In some places, there are dense tangles of Asparagus fern intermixed with 

native ground cover (e.g. Dianella and Lomandra) where hand removal of the weeds 




would result in major disruption to the native plants; in this situation selective cut and 

painting of the weed plant is acceptable providing the plant mass has already been 

checked and cleared of frogs. Tree stumps may need to be painted with other herbicides. 




Appendix 6 

Hygiene Protocol for the Control of Disease in Frogs 

(DEC 2000)

Green and Golden Bell Frogs - Gosford City Council

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