Assessing the effectiveness of ground - Department of Sustainability ...

Assessing the effectiveness of groundbased 

baiting for the control of wild dogs 

A. Robley, L. Woodford, P. Lee, V. Kingston, W. Peters, D. 

Klippell, A. Gormley 

2009 

Arthur Rylah Institute for Environmental Research 

Technical Report Series No. 193

Arthur Rylah Institute for Environmental Research Technical Series No. 193 

Assessing the effectiveness of ground-based baiting 

for the control of wild dogs 

Alan Robley, Luke Woodford, Peter Lee, Vaughn Kingston, Wayne Peters, David 

Klippell, and Andrew Gormley 


123 Brown Street, Heidelberg, Victoria 3084 

October 2009 

In partnership with: 

Department of Primary Industries, Victoria 


Department of Sustainability and Environment 

Heidelberg, Victoria

Report produced by: Arthur Rylah Institute for Environmental Research 

Department of Sustainability and Environment 

PO Box 137 

Heidelberg, Victoria 3084 

Phone (03) 9450 8600 

Website: www.dse.vic.gov.au/ari 

© State of Victoria, Department of Sustainability and Environment 2008 

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permitted under the Copyright Act 1968, no part may be reproduced, copied, transmitted in any form or by any means 

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or email customer.service@dse.vic.gov.au 

Citation: Robley, A., Woodford, L., Lee, P., Kingston, V., Peters, W., Klippell D., and Gormley, A. (2009) Assessing 

the effectiveness of ground-based baiting for the control of wild dogs. Arthur Rylah Institute for Environmental 

Research Technical Report Series No. 193. Department of Sustainability and Environment, Heidelberg, Victoria 

ISSN 1835-3827 (print) 

ISSN 1835-3835 (online) 

ISBN 978-1-74242-294-7 (print) 

ISBN 978-1-74242-295-4 (online) 

Disclaimer: This publication may be of assistance to you but the State of Victoria and its employees do not guarantee 

that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore 

disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in 

this publication. 

Front cover photo: Wild Dog (Alan Robley) 

Authorised by: Victorian Government, Melbourne 

Printed by: PRINTROOM 77 St Georges Rd, Preston 3072 

ii

Contents 

List of tables and figures...................................................................................................................2 

Acknowledgements............................................................................................................................3 

Summary............................................................................................................................................4 

1 Introduction.............................................................................................................................5 

2 Methods....................................................................................................................................6 

2.1 Study site...................................................................................................................................6 

2.2 Wild dog capture.......................................................................................................................7 

2.3 Baiting.......................................................................................................................................7 

2.4 Cameras ....................................................................................................................................8 

2.5 Wild dog area of use .................................................................................................................9 

2.6 Movement rates.........................................................................................................................9 

3 Results......................................................................................................................................9 

3.1 Wild dogs at Deptford and Merrijig..........................................................................................9 

3.2 Bait take ..................................................................................................................................10 

3.2.1 Deptford...................................................................................................................10 

3.2.2 Probability of encountering and taking a bait..........................................................11 

3.2.3 Merrijig....................................................................................................................12 

3.3 Area of use and rates of movement.........................................................................................12 

3.3.1 Deptford...................................................................................................................12 

3.3.2 Merrijig....................................................................................................................12 

3.3.3 Comparisons of area used........................................................................................14 

4 Discussion ..............................................................................................................................15 

References........................................................................................................................................17 

Appendix 1 Example images of the nine wild dogs identified by cameras at Deptford............19 

Appendix 2 Estimated costs of wild dog control at Deptford (eastern Victoria) and Merrijig 

(north-eastern Victoria)..................................................................................................................21

Assessing the effectiveness of ground-based baiting for the control of wild dogs 

List of tables and figures 

List of tables 

Table 1. Details of wild dogs captured at Deptford and Merrijig....................................................... 9 

Table 2. Number of baits taken and the number of detections of species taking baits or present at 

bait stations at Deptford.......................................................................................................... 10 

Table 3. Wild dog home range estimates from studies in Australia ................................................. 14 

List of figures 

Figure 1. Deptford study location....................................................................................................... 6 

Figure 2. Merrijig study location. ....................................................................................................... 6 

Figure 3. Wild dog fitted with GPS/satellite collar............................................................................. 7 

Figure 4. Digital heat-in-motion camera set at bait station................................................................. 8 

Figure 5. Wild dogs recovered at Deptford. ..................................................................................... 11 

Figure 6. Cumulative bait take by wild dogs at Deptford recorded from digital cameras................ 11 

Figure 7. Area of activity (95% MCP) for the four wild dogs at Deptford, August 2008–January 

2009 showing track network and location of cameras and bait stations................................. 13 

Figure 8. Area of activity (95% MCP) for the six wild dogs at Merrijig, February–May 2009 

showing track network and location of cameras and bait stations.......................................... 13 

2 Arthur Rylah Institute for Environmental Research Technical Report Series No. 193

Acknowledgements 


We thank the Department of Primary Industries (DPI) for logistical support throughout this project. 

This project was funded by the DPI, Victoria. Wildlife Unlimited assisted in the collection of field 

data. We thank the Gippsland and North East Wild Dog Management groups for their continued 

support. This work was conducted under the Department of Sustainability and Environment (DSE) 

Animal Ethics Committees permit number 09/09. Our thanks to Dave Forsyth and Lindy Lumsden 

for improving earlier drafts of this report. 

Arthur Rylah Institute for Environmental Research Technical Report Series No. 193 3

Summary 


Baits containing the poison 1080 (sodium fluoroacetate) are a common tool used to reduce wild dog 

numbers around Australia. In Victoria, the use of ground-based baiting is part of an integrated wild 

dog management strategy. 

This project aimed to quantify the effectiveness of buried baiting for the control of wild dogs in 

Victoria. We assessed the number of captured and released wild dogs that were subsequently killed 

by baiting. We also used cameras placed at bait stations that were activated by heat-in-motion to 

assess the visitation rate of wild dogs to bait stations. 

We captured and attached Global Positioning System (GPS) data-logging collars to four wild dogs 

at a site near Deptford in Gippsland during spring 2008 and six wild dogs at a site near Merrijig 

during autumn 2009 in the north-east of Victoria. The nightly capture probability at Deptford (0.73 

± 0.36 SE) was similar to Merrijig (0.95 ± 0.38 SE) indicating that underlying dog density was 

similar at the two sites. 

Digital heat-in-motion activated cameras placed at bait stations recorded the presence of a further 

five dogs at Deptford and three dogs at Merrijig. The combined method of recording collared dogs 

and individually identified dogs captured by cameras provided an estimate of the known population 

of wild dogs at each site. 

Poisoned baiting was undertaken by Department of Primary industries, Victoria (DPI) staff using 

standard operating procedures at both sites for seven weeks with predator meat baits containing 4.5 

mg of 1080. Baiting killed six wild dogs at Deptford (70% of the known population) and one wild 

dog at Merrijig (11% of the known population). 

The probability that a dog would encounter a bait station with bait in it over the course of the 

operation was on average 43%, and having encountered the bait station, the probability of a dog 

taking bait was on average 25% at Deptford. 

Lace Goannas (Varanus varius) (at Deptford) and foxes (Vulpes vulpes) (at Merrijig) were the main 

species that consumed bait. A range of other species were recorded at bait stations, including nontarget 

wombats, lyrebirds, native and introduced rodents, and wallabies. 

Wild dog controllers’ assessment of bait take by various species differed from that recorded by 

digital cameras. The difference is likely to be due to the difficulty of reliably identifying tracks 

several days after the species has taken the bait. In light of this, we recommend that bait take not be 

used as a measure of reduction in wild dog numbers following a baiting operation. 

The results from these trials indicate that buried baiting is likely to be a cost-effective tool in the 

management of wild dogs. Variation in success between the two sites could in part be accounted for 

by differences in landscape features, e.g. road density, which contributed to a difference in the 

spatial arrangement of baits in relation to the area used by wild dogs. 


1 Introduction 


Baits containing the poison 1080 (sodium fluoroacetate) are commonly used to reduce wild dog 

numbers around Australia. Despite this widespread use in other parts of Australia, baiting in 

Victoria is limited by a lack of quantitative data on its effectiveness under Victorian conditions. 

In temperate south-eastern Australia, the predation of livestock by wild dogs—wild-living members 

of the species Canis familiaris, including feral dogs (C. f. familiaris), dingoes (C. f. dingo) and their 

hybrids—affects the profitability of graziers whose holdings are adjacent to or within terrain 

inhabited by wild dogs (Fleming and Kom 1989). In accessible terrain in NSW, ground baiting is 

preferred by Wild Dog Control Association members to aerial baiting for the control of wild dogs 

(Fleming et al. 1996). Ground baiting requires fewer baits and the baiters have more control over 

the placement of baits. However, the efficacy of existing ground-baiting programs in Victoria 

remains unclear. 

The Victorian Wild Dog Management Strategy’s two main aims are to ensure best practices are 

used in the control of wild dogs and effective research is undertaken to fill gaps in our knowledge. 

The North East and Gippsland Wild Dog Management Plans both indicate that baiting should be 

incorporated into regular control programs. A key gap in our knowledge is a robust and generalised 

demonstration of the effectiveness of the buried-baiting technique under Victorian conditions. The 

targeted use of baits would greatly reduce the amount of toxin in the environment, and enable 

public land managers to establish clear guidelines for best management practices. 

A number of studies using changes in indices of abundance have investigated the effectiveness of 

baiting for the control of wild dogs in Australia. A ground-based baiting campaign with small meat 

baits containing 20 mg of 1080 in central Australia achieved a 69% reduction in dingo sign (Best et 

al. 1974). In the arid zone of South Australia, a single placement of 430 baits achieved a reduction 

of 10–13% of 300–400 dingoes that were watering at a single bore (Bird 1994). Fleming et al. 

(1996) assessed the efficacy of a baiting program that replaced taken baits on a daily basis. Wild 

dog abundance indices were calculated from visits to stations containing non-toxic baits before and 

after a replacement-baiting program. The program achieved a mean reduction of 76.1% in the index 

of wild dog abundance. Only one other study has assessed the actual kill rate of a baiting program. 

In New South Wales, using two placements of poisoned meat baits, two of nine (22%) radiocollared 

wild dogs were killed (McIlroy et al. 1986). 

We used both direct and indirect measures of changes in wild dog abundance to assess the 

effectiveness of buried baiting. We attached GPS collars to wild dogs to provide a direct measure of 

individuals killed from baiting. This also allowed for an assessment of wild dog movement in areas 

adjacent to private land. 

Heat-in-motion activated cameras have been used to survey the presence of a wide range of species 

both in Australia and elsewhere (Tobler et al. 2008; Towerton et al. 2008). Remote cameras can 

operate in all weather conditions, collect more reliable information on species’ identity, and for the 

information returned, they are cost effective. Images collected by heat-in-motion activated cameras 

can be used to assess the rate of bait take by target and non-target animals. 

This project aimed to quantify the effectiveness of buried baiting for the control of wild dogs in 

Victoria by assessing the number of captured and released wild dogs that succumbed to baiting and 

by assessing the visitation rate of wild dogs to bait stations via images recorded by heat-in-motion 

activated cameras placed at bait stations. This will provide critical information for future 

management of the control of wild dogs. 


2 Methods 


2.1 Study site 

We captured wild dogs in state forest north of Bairnsdale in eastern Victoria at a site near Deptford 

(147 o 35′E, 37 o 37′S; Fig. 1) in August 2008. A second site was north-east of the township of 

Merrijig in north-east Victoria (146 o 9′E, -37 o 2′S; Fig. 2), with trapping occurring in January 2009. 

Both sites were within 3–5 km of the public/private land interface, and had no wild dog control 

within the previous 12 months. 

Bullumwaal 

Figure 1. Deptford study location. 

Merrijig 

Figure 2. Merrijig study location. 

Deptford 

6 Arthur Rylah Institute for Environmental Research Technical Report Series No. 193 

LEGEND 

ÊÚ 

Deptford study area 

Roads 

Sealed road 

Unsealed track 

Land Tenure 

Freehold 

State Forest 

N 

0 2 4 Km 

LEGEND 

Study area 

Roads 

Sealed road 

Unsealed road 

Land Tenure 

Freehold 

State Forest 

Parks 

N 

ÊÚ 

0 2 4Km 

ÊÚ


2.2 Wild dog capture 

At Deptford, 26 padded Lanes dog traps (Coast to Coast Vermin Traps, Baldivis, WA) were set for 

21 consecutive days in August 2008 (i.e., a total of 546 trap nights). At Merrijig, 30 Lanes dog 

traps were set for 21 consecutive days in January and February 2009 (i.e., a total of 630 trap 

nights). All traps were operated by wild dog controllers from the Victorian Department of Primary 

Industries (DPI) following standard operating procedures (DCE 1991). Traps were set on dog sign 

identified by the wild dog controller (scat or scratching). All traps were set within 1 m of the side of 

tracks and roads. Traps were checked daily and captured dogs were initially subdued using a ketchall 

pole (Ketch-all Co., California, USA), and restrained on a holding board with broad straps fitted 

to their waist, shoulders and neck. Each dog had its capture location, sex, and weight recorded. 

Each dog was fitted with a collar housing a GPS data logger (Sirtrack, Haveloch North, New 

Zealand; Fig. 3) linked to the Argos satellite network (http://www.argos-system.org). The GPS unit 

estimated a location every 60 minutes. Data from GPS–Argos linked collars include a horizontal 

dilution of position (HDOP) as well as the number of satellites used to calculate the location. A low 

HDOP value represents better GPS positional accuracy due to the wider angular separation between 

the satellites used to calculate a GPS unit’s position. The maximum allowable error (MAE) in 

location accuracy was determined using the formula: A * HDOP, where A is the GPS device 

accuracy (MAE; http://www.developerfusion.co.uk/show/4652/3/). The GPS receiver was a 

Navman Callisto module and had an estimated accuracy of 2.5 m (Navman Wireless OEM 

Solutions 2006). Thus, the MAE for a HDOP of six is 15 m; we excluded all locations with a 

HDOP of > 6 in all analyses. 

Collars were also fitted with a Very High Frequency (VHF) transmitter and a timed-release 

mechanism programed to release 75 days after wild dogs were captured. Collars were retrieved 

after the release date by tracking the VHF transmitter on foot. 

Figure 3. Wild dog fitted with GPS/satellite collar. 

2.3 Baiting 

The DPI wild dog controllers conducted the baiting operation. Predator meat baits (150–200 g 

boneless red meat) containing 4.5 g of 1080 (sodium fluoroacetate) were prepared by Gippsland 

Environmental Services Pty, Bairnsdale, Victoria. Baits were placed in pre-prepared bait stations, 

to a depth of 5–10 cm. When changing baits, wild dog controllers from DPI attempted to identify 

species that either took bait or visited bait stations from sign. 

At Deptford, baits were checked and replaced every two weeks initially and then on a weekly basis 

for the final three weeks. The change in replacement rate was initiated to reduce bait decay after 

daily temperatures exceeded 30 o C. At Merrijig, baits were checked and replaced on a weekly basis. 

A sample of liver was retrieved from dead dogs and sent to the Alan Fletcher Research Station, 



Queensland Primary Industries and Fisheries Department for assays to determine the presence of 

residual 1080. 

We determined the nature of the distribution of bait stations at each site using the nearest neighbour 

method in Arcview 3.3 (ESRI California), which determines if a distribution is clumped, uniform or 

random. The distance of each individual bait station to its nearest neighbouring bait station was 

recorded. For two individual stations that are each other’s nearest neighbour, the distance is 

recorded twice, once for each station. The average distance between nearest neighbours is 

compared to the expected distance in the case of random distribution to give the ratio R: 

R= 1 

mean distance 

density 


2 

If R is equal to 1 then the population is randomly dispersed. If R is significantly greater than 1 the 

population is evenly dispersed. Lastly, if R is significantly less than 1 the population is clumped. 

2.4 Cameras 

Heat-in-motion triggered digital cameras were set at 26 bait stations from 17 September 2008 to 15 

November 2008 (1539 camera days) at Deptford. At Merrijig, cameras were set at 23 bait stations 

from 2 February 2009 to 8 April 2009 (1495 camera days). Images of animals at bait stations or 

passing on the road were recorded using Reconyx RapidFire TM ProPC90 heat-in-motion activated 

digital cameras (Reconyx, LLP Wisconsin, USA; Fig. 4). These cameras record 3.1 mega-pixel 

colour images during daylight and 3.1 mega-pixel infra-red images at night. These cameras were 

set to record three images as fast as possible once motion was detected (on average two images 

every three seconds) and to keep recording images as long as motion was detected. 

Individual dogs were identified by first grouping images by broad coat colour, (e.g. yellow, sable, 

black, and brindle). Within these groups, individual dogs were identified by assessing multiple 

images and comparing markings (e.g. presence, location and size of socks, colouration around 

muzzles, and chest markings), signs of age (e.g. grey muzzle and greying of coats), sex (males v 

females where visible) and physical condition. Dogs that could not be assigned to an individual 

were not counted. 

Digital camera 

Figure 4. Digital heat-in-motion camera set at bait station. 

Bait station


2.5 Wild dog area of use 

Area of use of each individual fitted with a GPS collar was calculated by the 95% minimum convex 

polygon (MCP) (Jenrich and Turner 1969) using the Home Range Analysis extension (Jenness 

Enterprises, Arizona, USA) in ArcView 3.2. We also compared the areas of use with estimates 

from previous Australian studies. 

2.6 Movement rates 

Movement rate was calculated by first determining the distance (m) moved between each 

successive location and the time interval (h) between the two locations and then dividing distance 

moved by the time to derive mean hourly velocity (m h -1 ). 

3 Results 

3.1 Wild dogs at Deptford and Merrijig 

Four wild dogs were captured (0.73 captures per 100 trap nights ± 0.36 SE) and collared at 

Deptford (two males and two females; Table 1). One female had swollen nipples indicating recent 

weaning. 

Six wild dogs were captured and collared (0.95 captures per 100 trap nights ± 0.38 SE) at Merrijig 

(three females and three males; Table 1). 

Table 1. Details of wild dogs captured at Deptford and Merrijig. 

Location Capture date ID Sex Weight 

(kg) 

Dog colour Date found 

dead 

Deptford 26/08/2008 D904 F 17 Brindle 13/11/2008 

Deptford 3/09/2008 D905 F 19 Yellow / Brindle – 

Deptford 29/08/2008 D907 M 25 Yellow – 

Deptford 3/09/2008 D909 M 20 Yellow 15/11/2008 

Merrijig 16/01/2009 D906 F 14 Black, white chest, white 

feet 

Merrijig 15/01/2009 D911 F 13 Black, white legs, grey 

muzzle 

Merrijig 18/01/2009 D914 F 14 Yellow/ginger, faint white 

feet 

Merrijig 28/01/2009 D910 M 19 Black, white chest and 

socks, white tip tail 

Merrijig 18/01/2009 D912 M 16 Ginger – 

Merrijig 17/01/2009 D915 M 17 Sable, yellow, white legs – 

Arthur Rylah Institute for Environmental Research Technical Report Series No. 193 9 

– 

– 

– 

–

3.2 Bait take 


3.2.1 Deptford 

Thirty bait stations were established at Deptford (26 with cameras). This represented one bait 

station for every eight kilometres of road in the area used by collared dogs or 0.10 baits/ km 2 . The 

average distance between bait stations was 1493 m. The nearest neighbour analysis indicated that 

bait stations were randomly distributed (z = 1.171 and R = 0.880). 

A total of 192 poison baits were laid over the 51 days of baiting. DPI wild dog controllers recorded 

bait take by wild dogs (7), wild dog/fox (13), and fox (9; Table 2). No other species were identified 

by sign at bait stations by wild dog controllers. 

Nine individual wild dogs were identified from images captured by the digital cameras, including 

three collared dogs (Appendix 1). Wild dogs were detected by cameras at 54% of bait stations. This 

included wild dogs walking past, investigating, and taking bait. 

Table 2. Number of baits taken and the number of detections of species taking baits or present at 

bait stations at Deptford 

Species 

Bait taken 

(including bait 

stations with 

no cameras) 

DPI records Camera Records 

Bait taken 

(only at bait 

stations with 

cameras) Bait taken 


Present at 

bait 

station* 

Wild dog 11 7 6 7 

Wild dog/fox 18 13 – – 

Fox 18 9 1 5 

Unknown 8 3 – – 

Rodent spp 0 0 1 0 

Goanna 0 0 10 19 

Wombat 0 0 0 21 

Total 55 32 18 52 

* Present—walking on, sniffing and /or scratching around bait station. 

Digital cameras detected six wild dogs taking baits (70% of the identifiable dogs in the area; Table 

2). Two of the four collared wild dogs were recorded taking baits and both dogs were subsequently 

recovered dead (Fig. 5). One of these was recovered two days after being photographed taking a 

bait. Analysis of a small portion of liver was unable to detect residual traces of 1080. The second 

dog was recovered in a decayed and mummified state and no tissue sample was available for 

analysis. Cameras also detected wild dogs at bait stations on seven other occasions during the 

baiting program.


Figure 5. Wild dogs recovered at Deptford. 

Bait take by wild dogs tended to occur more towards the later stages of the 51 days of the program 

(Fig. 6). 

Cumulative bait take 

7 

6 

5 

4 

3 

2 

1 

0 

1 5 9 13 17 21 25 29 33 37 41 45 49 

Figure 6. Cumulative bait take by wild dogs at Deptford recorded from digital cameras. 

Digital cameras recorded foxes at eight of the 26 bait stations on 17 separate occasions. Over the 

course of the entire baiting program (51 days) foxes walked past bait stations on 11 occasions 

(22%), investigated bait stations five times (10%) and were detected taking bait on one occasion 

(2%). 

Feral cats were detected at 19 of the 26 bait stations, but were never recorded investigating or 

taking bait. Over the course of the baiting program, goannas were recorded at 17 bait stations on 23 

occasions (45%). Goannas were detected taking bait on 10 occasions and scratching at bait stations 

on 10 occasions. Wombats were detected scratching and walking over 13 bait stations but never 

taking bait. 

3.2.2 Probability of encountering and taking a bait 

The probability that a dog encountered a bait station on a single day at Deptford was 0.015 ± 

0.0033 SE. However, there were times when bait stations did not contain bait due to another wild 

dog, a fox or goanna having already taken the bait. The corrected probability that a wild dog 

encountered a bait station with bait present on a single day was 0.0115 ± 0.0031 SE. 

Day 



At Deptford, wild dogs were recorded at bait stations with baits present on 13 occasions, with six of 

these resulting in bait take; hence the corresponding probability of bait take given an encounter 

with a baited bait station was 0.429 ± 0.132 SE. 

The probability that a wild dog encountered a bait station with bait present and took the bait on any 

given day is 0.0115*0.429 = 0.00494 ± 0.0020. During the course of the Deptford trial (51 days), 

the overall probability that a bait was taken was 0.25 ± 0.10 or 25%. 

3.2.3 Merrijig 

Twenty-three bait stations were established at Merrijig. This represented one bait station for every 

four kilometres of road within the area used by all the collared dogs (0.19 baits / km 2 ). The average 

distance between bait stations was 2960 m. The nearest neighbour analysis indicated that bait 

stations had a tendency towards clumping (z = 3.304 and R = 0.640). 

A total of 184 poison baits were laid over the 62 days of baiting. DPI wild dog controllers recorded 

bait take by wild dog (1), fox (3) and unknown (34). No other species were identified from sign at a 

bait station by wild dog controllers. 

Cameras operated for an average of 63 days (range 45–65 days). Six individual wild dogs were 

identified from images captured by the digital cameras, including three collared dogs. Wild dogs 

were detected by cameras at 35% of bait stations. This included wild dogs walking past, 

investigating, and taking bait. Digital cameras detected wild dogs at eight of the 23 bait stations on 

nine separate occasions, and one wild dog taking bait (11% of the identifiable dogs in the area) on 

the 9 February, 6 days into the baiting program. No collared wild dogs were recorded taking baits. 

Digital cameras recorded foxes at 16 of the 23 bait stations on 42 separate occasions and were 

detected taking bait on 15 occasions (65%). Feral cats were detected at 22 of the 23 bait stations on 

23 separate occasions, but were never recorded investigating or taking bait. No goannas were 

recorded at bait stations. Wombats were detected at 17 bait stations on 46 separate occasions. 

Wombats were detected 21 times scratching and walking over bait stations but never taking bait. 

The low level of bait take at this site prevented us from determining the probability of bait being 

taken. 

3.3 Area of use and rates of movement 

3.3.1 Deptford 

GPS data at Deptford were collected between August 2008 and January 2009. Wild dogs had areas 

of use ranging between 48 km 2 and 94 km 2 for the six month period of the study. All wild dogs had 

access to bait throughout the study (Fig. 7). 

Mean hourly distance moved by males was 241 m h -1 (range 1–19,559 m h -1 ; median 49 m h -1 ) and 

for females 230 m h -1 (range 1–9844 m h -1 ; median 37 m h -1 ). 

3.3.2 Merrijig 

GPS data at Merrijig were collected between February 2009 and May 2009. Wild dogs had areas of 

activity ranging between 17 km 2 and 30 km 2 for the 2.5 month period of the study. All wild dogs 

had access to some baits throughout the study (Fig. 8). 

Mean hourly distance moved by males was 243 m h -1 (range 1–3499 m h -1 ; median 92 m h -1 ) and 

for females 261 m h -1 (range 1–3219 m h -1 ; median 91 m h -1 ). 


# 

Bullumwaal 

# 

Bullumwaal 

# 

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# 


# 

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Deptford 

# 

Deptford 

LEGEND 

N 

0 2 4 Km 

Arthur Rylah Institute for Environmental Research Technical Report Series No. 193 13 

ÊÚ 

# Camera locations 

# Bait stations 

Home Range 

F-905 (94 km2) 

F-904 (54 km2) 

M-909 (48 km2) 

M-907 (73 km2) 

Roads 

Sealed road 

Unsealed track 

Land Tenure 

Freehold 

State Forest 

Figure 7. Area of activity (95% MCP) for the four wild dogs at Deptford, August 2008–January 

2009 showing track network and location of cameras and bait stations. 

# 

# 

# 

# 

# 

# # # 

# 

# 

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# # # 

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# 

# 

Roads 

Sealed road 

Unsealed road 

Land Tenure 

Freehold 

Merrijig 0 2 N 4Km 

ÊÚ 

LEGEND 

# Bait & camera locations 

Home Range 

F-906 (17 km2) 

M-910 (23 km2) 

F-911 (22 km2) 

M-912 (30 km2) 

F-914 (25 km2) 

M-915 (23 km2) 

State Forest 

Parks and Reserves 

Figure 8. Area of activity (95% MCP) for the six wild dogs at Merrijig, February–May 2009 

showing track network and location of cameras and bait stations. 

ÊÚ


3.3.3 Comparisons of area used 

Differences in data collection and analysis methodologies, time of year, length of study and sample 

size and composition (age and sex) make direct comparisons of areas of use between studies 

difficult. Bearing these differences in mind, the area of use at Merrijig was smaller than reported in 

other studies, while Deptford was comparable to studies from Western and Central Australia. 

Female home ranges have generally been reported as smaller than males, but at Deptford this was 

not the case. This may in part be explained by the fact that at Deptford only two females were 

tracked. 

Table 3. Wild dog home range estimates from studies in Australia 

Author(s) Method of estimation Location Mean home range size 

(km 2 ) 


All Males Females 

Harden (1985) 100% MCP South-east Australia – 27 – 

McIlroy et al. (1986) 100% MCP South-east Australia 22 25 20 

Catling (pers. comm. in 

McIlroy et al. 1986) 

Catling (pers. comm. in 

McIlroy et al. 1986) 

Not reported East Australia 10 10 11 

Not reported East Australia 18 20 12 

Corbett (1995) Not reported Central Australia 67 98 47 

Thomson (1992) 95% MCP Western Australia – 85 56 

Eldridge et al. (2002) 95% MCP Northern Territory – 157 272 

Claridge et al. (2009) MCP South-east Australia 90 100 79 

Robley et al. (in press) 100% MCP 

95% MCP 

South-east Australia 100 

Deptford (this study) 95% MCP South-east Australia 67 60 74 

Merrijig (this study) 95% MCP South-east Australia 23 25 21 

78 

156 

124 

55 

45

4 Discussion 


The aims of this study were to assess the effectiveness of ground-based baiting as a technique for 

reducing wild dog numbers, and to determine the probability of a wild dog encountering a bait 

station, and once encountered, the probability of bait being taken. 

We assessed the fate of 10 wild dogs fitted with GPS–Argos satellite linked collars at two locations 

during a poison baiting operation. We also used digital cameras placed at bait stations to determine 

the number of dogs without collars visiting bait stations. Using information from the cameras, we 

were able to determine the probability that a wild dog would encounter a bait station, and 

subsequently take bait. 

The baiting operation at Deptford removed 70% of the identifiable wild dog population, including 

two of the four collared wild dogs, with bait take at this site tending to increase later in the baiting 

period. Non-target species (foxes and goannas) were also recorded taking baits, reducing the 

availability of baits to wild dogs. Non-target bait take contributed to a moderate probability of a 

bait being taken once found by a dog (25%). At Merrijig, 11% of the wild dog population, or one 

wild dog, was recorded taking bait. Foxes were a key non-target species recorded taking baits; no 

goannas were recorded at this site. The low level of bait take at this site prevented us from 

determining the probability of bait being taken. 

Results indicate that buried baiting is likely to be a useful and effective tool for killing wild dogs. 

However, the varied results indicate that its effectiveness may not be uniformly successful at all 

locations and at all times, and the moderate probability of bait take when a bait was encountered 

needs to be interpreted with care as it is based on data from only one site. 

There are a range of possible factors that may influence the success of a baiting program (e.g. 

degradation of 1080 in the baits over time, the removal of baits by non-target species, and/or the 

availability of natural prey; McIlroy et al. 1986). Other factors may include the underlying density 

of wild dogs in relation to the density of baits, and the density of baits in the landscape in relation to 

the movement patterns and area of use of wild dogs. 

A greater percentage of the population was killed by the baiting program at Deptford than at 

Merrijig. In part, this can be explained by the distribution of baits in the landscape. Baits at 

Deptford were randomly distributed across the area used by wild dogs compared to the clumped 

distribution at Merrijig. This difference was a result of the spatial arrangement of the roads at each 

site. Road density (length of road / total km 2 ) was higher at Deptford compared to Merrijig 

(0.85/km 2 v 0.75/km 2 ). The higher road density provided the opportunity to spread baits more 

widely across the landscape than at Merrijig, allowing a greater opportunity for wild dogs to 

encounter a bait station. 

The timing of the baiting program differed at each site. Baiting at Deptford was undertaken in late 

spring to early summer, and at Merrijig it was undertaken in late summer to early autumn. Baiting 

campaigns are traditionally undertaken from spring to autumn, although generally later in autumn 

and earlier in spring than was the case in our study (Fleming et al. 2001). Baiting at this time of 

year is related to either wild dog ecology (e.g. breeding season—autumn—or possible dispersal and 

movement of pups—spring) or livestock protection (e.g. lambing in spring). Differences in season 

per se are unlikely to explain the differences in the results in this study. 

At Deptford, cameras identified nine individual wild dogs, with 70% of these killed by the 51 day 

buried baiting program compared to the 21 days of trapping that potentially removed 40%, thus 

trapping removed more dogs per week (0.19) than baiting (0.12) in that area at that time. However, 

the requirement under the Prevention of Cruelty to Animals Act 1986 is to check traps on a 24 hour 

basis, whereas current Government policy is that baits can remain unchecked for 14 days. In the 

program at Deptford, this means that trapping would be approximately five times more expensive 

than baiting (Appendix 2). At Merrijig, traps caught six wild dogs and baiting removed one, hence 



trapping potentially removed more dogs per day than baiting (0.29 and 0.02 respectively) and cost 

40% less (Appendix 2). 

At both sites, bait take by non-target species was an issue. At Deptford, goannas removed 5% of 

baits, potentially reducing the effectiveness of that program, while at Merrijig, foxes removed 8%. 

McIlroy et al. (1985) assessed the sensitivity of V. varinus to 1080 poisoning, and from limited data 

suggested a LD50 of 119 g / kg -1 . They concluded that it is unlikely that reptiles face any direct 

poisoning risk from pest-poisoning campaigns involving 1080, given their high tolerance and the 

enormous amounts of poisoned bait that would have to be eaten. Thus it is extremely unlikely that 

goannas at Deptford would have suffered any mortality from consuming the predator meat baits 

which contain 4.5 mg/bait. Foxes are a known predator of stock and native wildlife and are targeted 

in control operations around Australia. Integrated pest management is a strategic aim of many 

control programs, thus the reduction of foxes, while impacting on programs specifically aimed at 

protection of stock from wild dog attacks, provides a benefit to both livestock and wildlife. 

The reason for the discrepancy between the number of bait takes and the species taking baits 

recorded by DPI and the digital cameras is not clear. It is likely to be a combination of the digital 

cameras failing to record bait takes on some occasions and wild dog controllers incorrectly 

assessing bait as being taken, when in fact it was still present in a bait station. Predator meat baits 

are 250 g of moist horse or kangaroo meat. Dirt from bait station adheres to the bait making it 

difficult to distinguish from sods of dirt. Placing the bait into a small hole and sieving dirt back on 

top of the bait may reduce the incidence of this happening. Differences in the identity of the species 

taking bait could be attributed to the difficulty in assessing species from sign several days after bait 

has been taken. In light of this we would recommend that bait take be discontinued as a measure of 

control program success. 

This work provides initial information on the efficacy of baiting as a control tool for wild dogs and 

non-target species encounters with bait stations. To assess the optimal strategies for the control of 

wild dogs adequately, we need meaningful a priori expectations of the level of population coverage 

achievable by differing densities of control devices (baits and/or traps). Spatially explicit models 

can simulate encounter rates between wild dogs and control devices at different road and control 

device densities. By applying a modelling approach, we can objectively control for confounding 

effects of differing bait and trap density, length of toxic bait availability, spatial constraints in 

placement of baits and traps, and different population densities. Population density is an issue 

because home-range size, and hence the probability that a wild dog will interact with devices 

located at different points within its home range, is likely to vary with density. The result will be 

that for a given underlying dog and road density we will be able to estimate the required control 

device density for a given reduction in wild dogs. This approach has been applied to optimising bait 

station density for the control of possums in New Zealand (Tompkins and Ramsey 2007). We 

recommend that the next phase of work be undertaken using the approach outlined above. 


References 


Best, L. W., Corbett, L. K., Stephens, D. R., and Newsome, A. E. (1974). Baiting trials for dingoes 

in Central Australia, with poison 1080’, encapsulated strychnine, and strychnine suspended 

in methyl cellulose. CSIRO Division of Wildlife Research, Technical Paper No. 30. 

Bird, P. (1994). Improved electric fences and baiting techniques — a behavioural approach to 

integrated dingo control. Unpublished Final Report on Project DAS 39 to the Wool 

Research and Development Corporation. 

Corbert, L. (1995). The Dingo in Australia and Asia. University of New South Wales Press Ltd, 

Sydney. 

Claridge, A., Mills, D., Hunt, R., Jenkins, D., and Bean, J. (2009). Satellite tracking of wild dogs in 

south-eastern mainland Australian forests: Implications for management of a problematic 

top-order carnivore. Forest Ecology and Management 258, 814–22. 

Department of Conservation and Environment (1991). VerminPac. Policies for vermin control. 

Department of Conservation and Environment, East Melbourne. 

Eldridge, S. R, Shakeshaft, B. J., and Nano, T. J. (2002). The impact of wild dog control on cattle, 

native and introduced herbivores and introduced predators in central Australia. Final Report 

to Bureau of Rural Sciences. Northern Territory Parks and Wildlife Commission, Alice 

Springs, Northern Territory, Australia. 

Fleming, P. (1996). Ground-placed baits for the control of wild dogs: evaluation of a replacementbaiting 

strategy in north-eastern New South Wales. Wildlife Research 23, 729–40. 

Fleming, P. and Kom, T. J. (1989). Predation of livestock by wild dogs in eastern New South 

Wales. Australian Rangelands Journal 11, 61–6. 

Fleming, P., Thompson, J. A., and Nicol, H. I. (1996). Indices for measuring the efficacy of aerial 

baiting for wild dog control in northeastern New South Wales. Wildlife Research 23, 665– 

74. 

Fleming, P., Corbert, L., Harden, R., and Thomson, P. (2001). Managing the impact of dingoes and 

other wild dogs. Bureau of Rural Science, Canberra. 

Harden, R. (1985). The ecology of the dingo in north-eastern New South Wales. I. Movements and 

home range. Australian Wildlife Research 12, 25–38. 

Jenrich, R. I. and Turner, F. B. (1969). Measurement of non-circular home range. Journal of 

Theoretical Biology 22, 227–37. 

McIlroy, J. C., King, D. R., and Oliver, A. J. (1985). The Sensitivity of Australian Animals to 1080 

Poison VIII. Amphibians and Reptiles. Australian Wildlife Research 12, 113-18. 

McIlroy, J. C., Cooper, R. J., Gifford, E. J., Green, B. F., and Newgrain, K. W. (1986). The effect 

on Wild Dogs, Canis f. familiaris, of 1080-poisoning campaigns in Kosciusko National 

Park, NSW. Australian Wildlife Research 13, 535–44. 

Navman Wireless OEM Solutions (2006). Jupiter 31 GPS receiver module data sheet. 

(http://www.navmanwirelessoem.com/uploads/TM/30/TM30qEQoinYQRhT58SZXMA/L 

A010811B_J31_DataSheet.pdf) Accessed November 2008. 

Person, J. (2005). Writing Your Own GPS Applications: Part 2. 

http://www.developerfusion.co.uk/show/4652/3/. Accessed November 2008. 

R Development Core Team (2008). R: A language and environment for statistical computing. R 

Foundation for Statistical Computing. Vienna, Austria. 



Robley, A., Gormley, A., Forsyth, D. M., Wilton, A., and Stephens, D. (in press). Movement and 

habitat use by wild dogs in eastern Victoria. Australian Mammalogy in press. 

Thomson, P. C. (1992). The behavioural ecology of dingoes in north-western Australia. IV. Social 

and spatial organisation and movements. Wildlife Research 19, 543–63. 

Thomson, P. C., Rose, K., and Kok, N. (1992). The behavioural ecology of dingoes in northwestern 

Australia. VI. Temporary extraterritorial movements and dispersal. Wildlife 

Research 19, 585–95. 

Tobler, M. W., Carrillo-Percastegui, S. E., Pitman, L. R., Mares, R., and Powell, G. (2008). Further 

notes on the analysis of mammal inventory data collected with camera traps. Animal 

Conservation 11, 187–9. 

Tompkins, D. M., and Ramsey, D. (2007). Optimising bait-station delivery of fertility control 

agents to brushtail possum populations. Wildlife Research 34, 67–76. 

Towerton, L. A., Penman, D. T., Blake, E. M., Deane, T. A., Kavanagh, P. R., and Dickman, R. C. 

(2008). The potential for remote cameras to monitor visitation by birds and predators at 

Malleefowl mounds. Ecological Management & Restoration 9, 64–7. 



Appendix 1 Example images of the nine wild dogs identified 

by cameras at Deptford. 

Identification of individuals was based on multiple images of animals from a variety of angles and 

times of day. These images are presented as examples only. 





Appendix 2 Estimated costs of wild dog control at Deptford 

(eastern Victoria) and Merrijig (north-eastern Victoria) 

Activity Task Person 

days 

Deptford 

Baiting Prepare bait stations and 

check and replace baits 

Number of 

operational 

days 

No. 

dogs 

killed 

Dogs 

killed 

per day 

Cost per dog 

killed * ($) 

7 52 6 0.12 583 

Trapping Set and check traps 25 21 4 0.19 3125 

Merrijig 

Baiting Prepare bait stations and 

check and replace baits 

7 52 1 0.02 3500 

Trapping Set and check traps 25 21 6 0.29 2083 

* Assumes $500/day labour and material costs 


ISSN 1835-3827 (print) 


ISSN 1835-3835 (online) 

ISBN 978-1-74242-294-7 2 Arthur (print) Rylah Institute for Environmental Research Technical Report Series No. 193 

ISBN 978-1-74242-295-4 (online)

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