Biodiversity Strategy - Gosford City Council - NSW Government

Whilst these two species appear morphologically similar, there are concerns that J acutus can
form extensive monocultures.
Effective and ongoing weed control programs are needed that target and control priority weeds,
regenerate native bushland to healthy functioning ecosystems and that address community
awareness as well as being proactive in the identification and control of emerging weed
species.
A - 7.4
Feral and Introduced Pest Animals
Key Threatening Processes recognised at State and Commonwealth level that affect
biodiversity are listed in Appendix 4. These include predation by introduced species such as the
European red fox, feral cat and by Plague or Mosquito Fish (Gambusia holbrooki). Other
recognised feral animal threats are competition and land degradation from introduced species
such as feral rabbits, goats, deer and honey bees.
Introduced species not only impact native wildlife through predation, but also through
competition (for food and habitat) and spread of diseases. For example, introduced birds and
feral bees reduce habitat areas by occupying valuable tree hollows. Several feral bird species
such as the common Indian myna, common starling, tree sparrow and house sparrow as well as
feral honey bees utilise tree hollows. The introduced black rat and feral cat can also take prey
from and nest in tree hollows These places added competition on local native species for
increasingly rare suitable habitat in the area. Introduced birds that impact local species include
the Indian mynah and mallard duck.
Tim Low (1999) in his book ‘Feral Future’ argues that it is not only non native animals and plants
that are the issue. The native noisy miner is a very aggressive bird that hassles other birds for
territory and kills native birds (Low 1999 and pers. observation). Sap-feeding insects called
psyllids can cause dieback in Eucalypt forests and it is thought that, in association with other
pressures such as weed invasion and tree stress, the native bell miner may contribute to
increased populations of psyllids and other sap sucking insects that contribute to tree dieback
(http://www.nationalparks.nsw.gov.au/npws.nsf/Content/bell_miner_dieback_strategy).
In the Gosford LGA, the introduced mammals of most concern at this stage are considered to
be foxes, wild dogs, feral deer and feral goats although further study is required to document
their distribution and abundance. Priorities will need to be reassessed as more knowledge is
gained about the extent and impact of feral pests in the region and control methods are trialled.
Some priority pest species are discussed in more detail below.
A - 7.4.1
Foxes
Foxes are a serious threat to biodiversity and are implicated in the decline of many threatened
species (NPWS 2001). For example, the draft Recovery Plan for Large Forest Owls states that
fledglings of the Powerful and Masked Owls are susceptible to predation by foxes (McNabb
1996, Kavanagh 1997, Debus 1997 quoted in NSW NPWS 2005) and that the risk of predation
by foxes on fledglings is widespread and likely to be correlated with proximity to disturbed areas
(Debus 1997 quoted in NSW NPWS 2005). Foxes are also a major threat to the endangered
Bush Stone-curlew and in at least one instance thought to have contributed directly to the death
of two curlews at Kincumber (pers comm. Catherine Price 2005). They also predate on many
waterbirds. Recent monitoring for Council’s fox baiting program in coastal reserves found that
foxes were abundant. At the same time there were very few records for native species,
suggesting that foxes may be having a significant impact on biodiversity in these reserves.
Biodiversity - Technical Report Page 156