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Feral Animal Monitoring and Control Programme
Final Report
WRFC5: May 2016
PREPARED FOR
CITY OF NEDLANDS (ON BEHALF OF)
WESTERN SUBURBS REGIONAL ORGANISATION OF COUNCILS
CLIENT
www.greeningaustralia.org.au
LCEM5
Feral Animal and Control Monitoring Programme
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This document has been prepared for the benefit of the Western Suburbs Regional Organisation of
Councils. No liability is accepted by this company or any employee or sub-consultant of this company
with respect to its use by any other person.
This disclaimer shall apply notwithstanding that the report may be made available to other persons for
an application for permission or approval to fulfil a legal requirement.
QUALITY STATEMENT
PROJECT MANAGERS PROJECT TECHNICAL LEAD
Liam Mulcahy Liam Mulcahy
PREPARED BY
Liam Mulcahy
CHECKED BY
Blair Parsons
REVIEWED BY
Vincent Cusack
APPROVED FOR ISSUE BY
Blair Parsons
GREENING AUSTRALIA (WA)
1 Underwood Avenue, Shenton Park, WA 6008
TEL +61 (08) 9287 8300
REVISION SCHEDULE
Rev No
Date Description Signature or Typed Name (documentation on file)
Prepared by Checked by Reviewed by Approved by
1.0 30/06/16 Preparation Liam Mulcahy
Blair Parsons
Vincent Cusack
Blair Parsons
Cover photo: Red Fox Vulpes vulpes
Feral Animal and Control Monitoring Programme
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Executive Summary
In August 2015, Greening Australia WA (GA) was commissioned by the City of Nedlands on behalf of
the Western Suburbs Regional Organisation of Councils (WESROC), to undertake a feral animal
monitoring and control program within their respective governance zones. This document reports on
activities undertaken by GA for the period August 2015 to May 2016, comprising:
1. a targeted baseline survey to provide quantitative data on the distribution and relative
abundance of foxes and rabbits in the WESROC area; and
2. a fauna control program targeting fox and rabbits in priority areas informed by, and subsequent
to, initial monitoring.
The baseline survey was undertaken over a 30 night period in which 38 motion sensor cameras were
installed across 26 parks and reserves across the WESROC area. Over the study period, motion
cameras captured brown rats on 188 occasions, cats on 73, rabbits on 37 and foxes on only 5. A number
of other introduced and native animals were also captured.
The subsequent targeted control of foxes and rabbits by the licensed feral animal contractor supported
evidence of low fox occurrence as no foxes were trapped during the trapping period. Rabbits were most
prevalent along the foreshore regions, and at sites within Bold Park, but due to public risk baiting was
only authorised at one site within the University of Western Australia (UWA) Field Station. Warren
fumigation was authorised by participating councils and was carried out at Peasholm Dog Beach.
In combination, both activities have provided valuable baseline data to inform future monitoring or
control efforts and identified key considerations to improve future implementation. When engaging in a
control program stakeholders must ensure:
ample time to promote public awareness and engagement;
consolidation and provision of local historical data relating to previous pest control efforts prior
to project commencement;
engagement of private organisations or landholders to gain full access to bush localities within
a study area; and
local Ranger patrols having the awareness and authorisation to promote the restriction of
domestic animals to approved exercise areas for the duration of proposed control activities.
Future control strategies should consider the inclusion of cats as target species as their abundance in
the landscape proved greater than the target species and they pose a significant threat to native wildlife.
It is essential that WESROC discuss what if anything should be done to control cats in the urban setting.
Feral Animal and Control Monitoring Programme
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Directions for discussion should reinforce requirements under the Cat Act 2011 and proposed actions
may include:
public education reinforcing the impacts of domestic cats on native wildlife;
enforcement of existing laws;
studies of domestic cats on urban bushland;
subsidised sterilization of cats; and
promotion of alternative pets.
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Contents Executive Summary .............................................................................................................................. 3
1 Introduction .................................................................................................................................... 6
2 Objectives ....................................................................................................................................... 6
3 Study Area ...................................................................................................................................... 6
1 Baseline Survey ............................................................................................................................. 8
1.2.1 Initial Consultation ............................................................................................................... 8
1.2.2 Motion Sensor Cameras ..................................................................................................... 8
1.2.3 Targeted Search................................................................................................................ 10
1.2.4 Habitat Assessments and Mapping................................................................................... 10
1.2.5 Citizen Science and Community Evidence Log ................................................................ 10
1.3.1 Habitat Assessment and Mapping .................................................................................... 10
1.3.2 Rabbits .............................................................................................................................. 10
1.3.3 Fox .................................................................................................................................... 12
1.3.4 Species Summary ............................................................................................................. 13
2 Animal Control Programme ........................................................................................................ 15
2.2.1 Initial Consultation ............................................................................................................. 15
2.2.2 Risk Assessment ............................................................................................................... 15
2.2.3 Trap installation ................................................................................................................. 16
2.2.4 Fox den fumigation ............................................................................................................ 16
2.2.5 Pindone Baiting ................................................................................................................. 16
2.2.6 Rabbit Warren Management ............................................................................................. 17
2.3.1 Rabbits .............................................................................................................................. 17
2.3.2 Fox Trapping ..................................................................................................................... 17
2.3.3 Den Fumigation ................................................................................................................. 17
3 Discussion .................................................................................................................................... 18
4 Appendices ................................................................................................................................... 22
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1 Introduction In August 2015, GA was commissioned to undertake a baseline survey to investigate distribution and
relative abundance of feral animals (namely foxes and rabbits) throughout key sites within the WESROC
area, and implement an initial control programme informed by the outcomes of this baseline survey. It
is intended that the results of the survey will provide baseline data and support for future monitoring
and control efforts.
2 Objectives The specific objectives of this programme were to:
undertake a targeted baseline survey to provide quantitative data on the distribution and relative
abundance of foxes and rabbits within the WESROC study area (including Bold Park);
provide quantitative data on the distribution and relative abundance of native fauna within the
WESROC study area;
conduct follow up control of rabbits and foxes in priority areas as informed by, and subsequent
to, initial monitoring and the requirements/constraints of individual councils;
provide recommendations for the future monitoring and management of foxes and rabbits and
native fauna in the study area.
The objectives and survey methods adopted for the duration of the programme aligned with relevant
guidelines and standard operating procedures. These included, but were not limited to:
Environmental Protection Authority (EPA) Position Statement 3 (2002) Terrestrial Biological
Surveys as an Element of Biodiversity Protection;
EPA and Department of Environment and Conservation (DEC) Technical Guide (2010)
Terrestrial Vertebrate Fauna Surveys for Environmental Impact Assessment;
DEC: Department of Environment and Conservation. (2011) Remote operation of cameras,
Standard Operating Procedure 5.2, April 2011;
DEC. (2009) Observing animals from secondary sign, Standard Operating Procedure 7.2, May
2009.
3 Study Area The WESROC study area (Figure 1) is approximately 6,330 ha in size and is located between Perth
and Fremantle, spaning from the coast to the Swan River. It contains a range of parks, bushland and
open space, ranging from wetlands, coastal dunes, river foreshore and small reserves to substantial
urban remnants such as Bold Park.
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Figure 1: WESROC Study Area
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1 Baseline Survey
Objective
MWH Global were contracted to undertake a baseline survey for a month long period across the
WESROC study area recording the presence of feral animal species and providing data to inform later
control efforts. Baseline data was derived from the three methodologies listed:
Motion Sensor Camera Installation;
Targeted Searches; and
Habitat Assessment
Methods
1.2.1 Initial Consultation
Prior to installation, representatives from WESROC were informed of GA’s intention for the roll out of
the program and an opportunity for discussion was facilitated at the WA Ecology Centre in Bold Park of
19 October 2016. Parties representing GA, MWH Australia, WESROC and Botanic Gardens and Parks
Authority (BGPA) were in attendance. Project procedure, OHS concerns and access issues were
discussed on the day and participation in the baseline survey was granted by all. The BGPA expressed
that they would not take part in the proceeding control program as authorisation was uncertain and the
procedure may hinder the proposed schedule of works.
1.2.2 Motion Sensor Cameras
Motion sensor cameras were deployed and locations recorded using a GPS at 38 sites within 26 parks
and reserves across the WESROC study area (Figure 1; Table 1). Reconyx HC600 cameras were
mounted to tree trunks/shrubs at an approximate height of 1 - 2 m above the ground and were discretely
located to hide them from human interference. The camera lens was directed towards open areas
capable of providing unobscured imagery of wildlife and secured using ‘Python Loops’ to further prevent
tampering or theft. Cameras were set to high sensitivity, taking bursts of three photos with a 15 second
(photo-free) interval. The timeframe of camera deployment was over a 30 night period between 2nd of
November and 4th of December 2015 and upon collection all batteries were still operational and SD
cards were never completely full, confirming survey effort.
Scented lure stations were simultaneously installed in open areas approximately 2 – 3 meters line of
site distance from the motion sensor camera. A universal attractant (peanut butter, oats and sardines)
and a sponge soaked in fish oil was inserted into a perforated 200 mm x 40 mm PVC pipe. This
combination provides a pungent attractant that was inaccessible to animals for the duration of the
monitoring period. Scented Lures were secured to trees, shrubs or fallen debris using cable ties. Motion
sensor cameras in combination with baiting was a strategy employed to improve the likelihood of
capturing foxes as a long-term attractant for rabbits is difficult to provide. Camera positioning towards
open areas was the strategy employed to increase the likelihood of also capturing grazing Rabbits.
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Table 1: Site location and habitat information
Site Habitat Type Location Coordinates
Latitude Longitude
WESROC-01 Coastal Heath Peasholm Dog Beach -31.9113 115.7572
WESROC-02 Coastal Heath - -31.9278 115.7593
WESROC-03 Eucalypt Woodland Bold Park -31.9314 115.7774
WESROC-04 Eucalypt Woodland Wembley Gold Course -31.9273 115.7863
WESROC-05 Wetland Lake Monger Reserve -31.9243 115.8273
WESROC-06 Wetland Lake Monger -31.9292 115.8322
WESROC-07 Banksia Woodland Bold Park -31.9447 115.7632
WESROC-08 Banksia Woodland Bold Park -31.9432 115.7705
WESROC-09 Banksia Woodland Bold Park -31.9471 115.7708
WESROC-10 Eucalypt Woodland Bold Park -31.9517 115.7639
WESROC-11 Pine Plantation Bold Park -31.9514 115.7736
WESROC-12 Eucalypt Woodland UWA Bushland -31.9499 115.8007
WESROC-15 Coastal Heath Bold Park -31.9622 115.7674
WESROC-17 Eucalypt Woodland Shenton Bushland -31.9605 115.7996
WESROC-18 Eucalypt Woodland - -31.9684 115.7801
WESROC-19 Coastal Heath North Swanbourne Reserve -31.9766 115.7567
WESROC-20 Eucalypt Woodland Allan Park -31.9785 115.7601
WESROC-21 Wetland Lake Claremont -31.9709 115.7785
WESROC-22 Eucalypt Woodland Hollywood Reserve -31.9694 115.8049
WESROC-23 Eucalypt Woodland Hollywood Reserve -31.9721 115.8031
WESROC-24 Coastal Heath Coastal Reserve -31.9879 115.7538
WESROC-25 Coastal Heath John Black Dune Park -31.9918 115.7538
WESROC-27 Eucalypt Woodland Foreshore Reserve -31.9939 115.7725
WESROC-29 Coastal Shrubland Matilda Bay Reserve -31.9864 115.8243
WESROC-30 Eucalypt Woodland Point Resolution Reserve -32.0021 115.7917
WESROC-31 Eucalypt Woodland Beaton Park -32.0008 115.8069
WESROC-32 Eucalypt Woodland Bay View Park -32.0094 115.7708
WESROC-33 Coastal Shrubland - -32.0162 115.7547
WESROC-34 Coastal Shrubland Buckland Hill Park -32.0182 115.7556
WESROC-35 Coastal Shrubland Monument Hill Park -32.016 115.7609
WESROC-36 Coastal Shrubland Chidley Point Reserve -32.0173 115.7799
WESROC-37 Coastal Shrubland Minim Cove Reserve -32.023 115.7681
WESROC-38 Eucalypt Woodland UWA Bushland -31.95 115.803
WESROC-39 Banksia Woodland UWA Bushland -31.9569 115.8017
WESROC-40 Eucalypt Woodland Shenton Park Bushland -31.9583 115.8005
WESROC-41 Eucalypt Woodland Shenton Park Bushland -31.963 115.8003
WESROC-43 Coastal Heath Swanbourne Beach -31.9814 115.7539
WESROC-44 Eucalypt Woodland Lake Claremont -31.9734 115.774
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1.2.3 Targeted Search
At each of the 38 sites, targeted searches were conducted for 30 minutes during the installation and
retrieval phases of camera monitoring, totalling a one hour search duration at each site. Searches
catalogued specific evidence of fox and rabbit habitation observable as tracks, scats, latrine sites, bones
and burrows. A further targeted search was conducted during the control phase of the project.
1.2.4 Habitat Assessments and Mapping
At each site, representative areas of habitat were assessed and described for their complexity and
quality. Habitats important for hosting fauna of conservation significance were noted, and the extent of
their suitability for these species was documented. Habitat characteristics documented included habitat
extent, type, description and quality, ecological processes important to that habitat, soil type and colour,
landscape position, geology, landform, presence of significant features such as water bodies and
nests/roosts, extent of litter or other ground cover, fire age and disturbance levels.
1.2.5 Citizen Science and Community Evidence Log
Prior to the project commencement an article was printed in the Western Suburbs Weekly informing
local residents of proposed project aims and associated works. In conjunction, an online link was
established to allow the public to report information regarding fox sightings. Local friends groups were
notified by representatives of participating councils and encouraged to provide opportunistic
information.
Results
1.3.1 Habitat Assessment and Mapping
Six habitat types were recorded across the 38 survey sites. These habitats included Banksia Woodland,
Coastal Heath, Coastal Shrubland, Eucalypt Woodland, Pine Plantation and Wetland. The full habitat
assessment descriptions for each site can be referred to in Appendix 1.
1.3.2 Rabbits
The initial base line survey recorded evidence of rabbits at 16 sites and no evidence was identified at
the remaining 22 sites across the total WESROC survey area. Rabbit presence was confirmed via
motion sensor cameras at 10 of the 16 sites making them the fifth most commonly distributed species
out of 22 species observed (Plate 1). Rabbits were captured 37 times via motion sensor cameras and
were the sixth most observed species in the survey.
Motion sensor captures were highest at WESROC-19 followed by WESROC-29 sites both within the
coastal foreshore region. Evidence of Rabbits was found at six of the seven sites within Bold Park and
motion sensor evidence was captured at three Bold Park sites. Rabbit presence was most evident in
areas associated with the coastal foreshore and at sites within Bold Park (Table 2).
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Plate 1: Rabbit captured at WESROC 29 – Matilda Bay Reserve
Table 2: Location and details of Rabbit records
Site MC Targeted Search
Notes O S D T W
WESROC-01 x scats old and scarce
WESROC-07 1 x x 1 high amount of scat (fresh); warren active (T4)
WESROC-08 x x 1 high amount of scat (fresh and old); warren old (T4)
WESROC-09 x x high amount of scat (relatively fresh)
WESROC-10 2 x medium amount of scats (relatively fresh)
WESROC-11 x low amount of scat (few fresh)
WESROC-15 4 x x high amount of scat (fresh and old); tracks recent
WESROC-19 8 x x x 1 high amount of scat (mostly old); warren old (T4)
WESROC-24 3 x high amount of scat (fresh and old)
WESROC-29 7 2 two individuals observed; high amount of scats (fresh)
WESROC-30 5 x medium amount of scats (relatively fresh)
WESROC-33 2 x Diggings recent; no scats recorded
WESROC-34 x scats old and scarce
WESROC-37 x fresh scats recorded on nearby grassed area
WESROC-41 2
WESROC-43 3
MC = Motion-sensor Camera records; O = Observed; S = Scats; D = Diggings; T = Tracks; W = Warren
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1.3.3 Fox
Foxes were confirmed at ten sites across the Study Area and were recorded via motion-camera on five
occasions (Table 3, Plate 2). No sites recorded a Fox more than once.
Plate 2: Red Fox identified at WESROC-19 – North Swanbourne Reserve
Table 3: Location and details of Red Fox records
Site MC Targeted Search
Notes S T Di De
WESROC-01 1 1 one scat very old
WESROC-02 1 2 x one scat fresh; one scat very old; track fresh
WESROC-04 anecdotal evidence of regular sightings
WESROC-07 1 1 one scat fresh; at active Rabbit warren; old den (T4)
WESROC-08 4 four scats; individual recorded ~6 months prior
WESROC-09 1 one scat, relatively old
WESROC-10 x apparent (occupied) den close by but not found
WESROC-15 2 x very recent tracks, two relatively old scats
WESROC-19 1 2 one scat fresh; one scat very old
WESROC-21 1
WESROC-27 1? scat unconfirmed (possibly Dog)
WESROC-34 1 one scat fresh
WESROC-38 1? track old (possibly dog)
WESROC-43 x 1 old den; no evidence of recent use (T4)
WESROC-44 x diggings at base of fence, potentially dog (or other)
MC = Motion-sensor Camera records; S = Scats; T = Tracks; Di = Diggings; De = Den
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Scats were also collected from two additional sites which are likely to be from a fox. However, this
could not be positively confirmed due to the age of the scat. Four of the five sites where foxes were
recorded on motion sensor camera represent Coastal Heaths or Coastal Shrublands, the other being a
Wetland. An old den was also recorded from the Coastal Heath habitat (WESROC-43) although was
not in use at the time of survey.
The community provided evidence of two fox occurrences, one of which was just outside the study area.
Employees of the Wembley Golf Course noted that foxes were regularly recorded within the Golf
Course, particularly within the north-eastern section and around the lakes, where they presumably hunt
waterbirds. It was communicated that a fox had recently been found dead within the proximity of the
lake at the Golf Course. Beyond the Study Area, a fox was reported in Kings Park, crossing May Drive
entering bushland, emerging on Lovekin Drive and heading towards Forrest Drive.
1.3.4 Species Summary
Across all sites a total of 22 species were captured via motion sensor cameras, 13 of these species
were native and nine species were introduced (Table 4). The most common species captured by motion
camera was the Brown Rat (Rattus norvegicus) followed by the Cat (Felis catus, Plate 3) and then the
Bobtail Lizard (Tiliqua rugosa). These species were also those recorded at the greatest number of sites
(ie. Cat – 23 sites, Rat – 22 sites, Bobtail Lizard – 19 sites, Table 5). Introduced species comprised
four of the top six species listed for both Camera Captures and number of sites observed (Table 4, 5).
These species include the Rat, Cat, Dog and Rabbit.
Plate 3: Cat Identified at WESROC Site 12 – UWA Bushland
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Table 4: Total number of camera captures per species
Species Camera Captures
Brown Rat* 188
Cat* 73
Bobtail Lizard 60
Dog* 41
Australian Raven 38
Rabbit* 37
Spotted Turtle-Dove* 31
Laughing Turtle-Dove* 28
Australian Magpie 19
Dusky Moorhen 12
Common Brushtail Possum 12
Red Fox* 5
Buff-banded Rail 5
Laughing Kookaburra 4
King's Skink 4
Willie Wagtail 2
Purple Swamphen 2
West-coast Laterite Ctenotus 1
Sand Monitor 1
Red Wattlebird 1
Dugite 1
Australian White Ibis 1
* Introduced species
Table 5: Frequency of occurrence of individual species
Species Number of Sites Observed
Cat* 23
Brown Rat* 22
Bobtail Lizard 19
Rabbit* 10
Dog* 9
Laughing Turtle-Dove* 9
Australian Raven 8
Australian Magpie 6
Red Fox* 5
Spotted Turtle-Dove* 4
Common Brushtail Possum 4
Laughing Kookaburra 4
King's Skink 4
Purple Swamphen 2
Dusky Moorhen 1
Buff-banded Rail 1
Willie Wagtail 1
Feral Animal and Control Monitoring Programme
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Species Number of Sites Observed
West-coast Laterite Ctenotus 1
Sand Monitor 1
Red Wattlebird 1
Dugite 1
Australian White Ibis 1
* Introduced species
2 Animal Control Programme
Approach
Fox and Rabbit location data obtained during the baseline survey were used to inform the locations of
trapping sites for the Animal Control Program. WildThings Animal Control Solutions (WTACS) were
commissioned to implement the animal control program using humane methods, in accordance with
welfare requirements and the conditions of the supporting local councils.
Methods
2.2.1 Initial Consultation
On 12 January 2016, a meeting was held at the GA offices, providing an opportunity for WESROC
participants to liaise on the status of the project. Representatives from the City of Nedlands, Town of
Claremont, GA and WTACS attended. A key focus of the discussion was to clarify the preferred
methods to be undertaken during the control phase of the project. Variations in proposed control
methods included the exclusion of shooting and limitations on the distribution of poison baits. The
agreed set of control strategies to be implemented comprised:
trapping;
baiting;
fumigation; and
manual destruction of dens/warrens.
2.2.2 Risk Assessment
WildThings Animal Control Solutions undertook a control programme for a four week period from 11th
January to 10th February 2016. The primary task involved an assessment of sites identified in the
baseline survey to determine their requirement and suitability for control, targeting further evidence of
habitation through the identification of scats, tracks, dens or warrens. A comprehensive risk
assessment was carried out within 24 parks and reserves within the WESROC study area. Trapping
sites were selected based on the presence of fox activity, the probability of interaction between people
and trapped animals and the likelihood of capturing domestic animals.
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2.2.3 Trap installation
Trapping authorisation was granted through the Department of Agriculture and Food and 14 modified
foot hold traps were installed across nine WESROC sites targeting foxes (Table 6). Prior to installation
signage was installed at the entry points of reserves featuring traps and warning tape and further
signage was placed in close proximity to the trap site. Location of traps was recorded and traps were
systematically checked between 4:30 and 7:30 in the morning and reset in the afternoon. Traps were
left in situ for the duration of the trapping period and only removed if signs suggested familiarity, external
disturbance or interaction from domestic animals. All signage was removed at the conclusion of
trapping at the site.
Table 6: Trap Installation Sites
Site Name Latitude Longitude
Allan Park 31° 58’ 37. 05” S 115° 45’ 20.57” E
31° 58’ 36.54” S 115° 45’ 19.77” E
Bay View 32° 0’ 35.03” S 115° 46’ 15.58” E
Buckland Hill 32° 1’ 10.97” S 115° 45’ 15.85” E
32° 1’ 10.00” S 115° 45’ 16.54” E
Lake Claremont 31° 58’ 22.35” S 115° 46’ 38.99” E
31° 58’ 10.76” S 115° 46’ 46.38” E
Matilda Bay 31° 59’ 11.68” S 115° 49’ 27.24” E
North Swanbourne 31° 58’ 36.07” S 115° 45’ 20.16” E
Point Resolution 32° 0’ 14.48” S 115° 47’ 36.38” E
Shenton Park 31° 57’ 41.20” S 115° 47’ 58.27” E
UWA
31° 57’ 1.82” S 115° 48’ 11.83” E
31° 56’ 59.24” S 115° 47’ 49.65” E
31° 56’ 59.26” S 115° 47’ 49.84” E
2.2.4 Fox den fumigation
At Point Resolution 1 den was identified and fumigated. A smoke machine was used to inject smoke
into warrens so all surface openings could be identified. Secondary openings were manually sealed so
only one entry and exit point remained at a den site. A carbon monoxide cartridge was ignited and
placed inside the entrance to dens and then covered over. DEN-CO-FUME was the preferred product
used by the contractor for this project.
2.2.5 Pindone Baiting
Baited oats laced with Pindone were broadcast by hand at the UWA Field Station to localised areas
exhibiting evidence of rabbit habitation. Pindone is an accumulative poison and required three
applications over 10-14 days to be effective. WildThings Animal Control Services used non-germinating
sterilised oats for this baiting.
Feral Animal and Control Monitoring Programme
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2.2.6 Rabbit Warren Management
Fumigation was a chosen control methodology in areas of rabbit presence where the use of Pindone
and 1080 was not appropriate. An active warren site was identified at Peashold Dog Beach and the
following fumigation methodology was conducted. A smoke machine was used to inject smoke into the
warren to identify surface openings. Once all openings were identified, they were backfilled leaving
only one for the application of the fumigant. A long pipe was inserted into the remaining opening and
backfilled leaving the pipe exposed. Phosphine in the form of QuickPhos tablets were dropped into the
pipe followed by water to activate the tablet. The pipe was removed leaving activated tablets in the
warren. The remaining hole was backfilled.
Results
2.3.1 Rabbits
Pindone baiting was identified by the contractor as the most suitable chemical for baiting in the domestic
area. Permission to use Pindone baiting as a control method was granted by the Town of Cambridge
only; however, no rabbit baiting was required in this area. The UWA Field Station was the only site
where rabbit baiting was undertaken. No rabbit signs were recorded in the bushland areas at this site
during the baseline survey but evidence of occupation was found within crop trial areas adjacent to
bushland upon secondary inspection. Three applications of bait were applied over 10 days. Assessing
the effectiveness of this baiting is beyond the scope of this project.
A secondary survey (i.e. subsequent to the baseline survey) across all sites identified only one active
warren site located at Peasholm Dog Beach. This site was not identified in the original baseline survey.
This site was fumigated.
The program timing was deemed inappropriate for release of Rabbit Haemorrhage Disease (RHD) by
the contractor who has instead suggested a potential release date outside of the current schedule of
works. This release has been proposed for spring when vectors for transmission are greatest and the
contractor has agreed to do this outside of the works period but as part of the original contract.
2.3.2 Fox Trapping
Of the 26 parks and reserves included in the baseline survey, nine of these sites proved unsuitable for
trap installation as the risk of external interference and off target capture was deemed too high. Access
to an additional eight sites was also denied by both Bold Park and Wembley Golf Course. In total, 15
traps were installed across the remaining eight park and reserve sites.
Signs of fox habitation were observed at five sites (Point Resolution, Bayview, Buckland Hill, Lake
Claremont and Swanbourne) with only the latter two having multiple occurrences. These findings were
consistent with the baseline survey data. No foxes were caught during the control program.
2.3.3 Den Fumigation
The primary inspections and risk assessment component of the animal control program identified the
location of an active fox den at Point Resolution Reserve which was fumigated.
Feral Animal and Control Monitoring Programme
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3 Discussion
Rabbits
The baseline survey determined that rabbits were commonly distributed across the WESROC sites.
Rabbit populations were evident at coastal sites within the jurisdiction of Nedlands, Cottesloe, Subiaco
and Mosman Park. The actions implemented during the control phase of the program included Pindone
baiting and warren fumigation. The release of RHD was also planned for implementation; however, its
autumn release was not favoured by the contractor. Although outside of the project timeframe, a
springtime release has been scheduled by WTACS coinciding with the period of maximum vectors.
Within the WESROC public reserves, control options were limited to fumigation and manual warren
destruction as councils could not permit the use of baiting across their respective governance zones
due to perceived risk to domestic and native animals. The Town of Cottesloe abstained from Pindone
baiting in the foreshore area as it had already completed a baiting program during the summer months.
Despite restrictions on public reserves, permission to use bait was granted on private land within the
UWA site. The baseline survey failed to detect evidence of rabbits within the bushland at this site
however evidence was found during the control program around the field station and trial sites.
In the absence of historical warren data, a secondary survey was conducted across the WESROC study
area to locate warren sites. During this survey, a number of inactive warrens were located and only a
single active warren was fumigated at Peasholm Dog Beach. Fumigation and warren destruction was
not permitted by the City of Nedlands as they expressed concern for wildlife inhabiting vacant rabbit
warrens.
Fox
The baseline survey confirmed the presence of foxes within the WESROC Study Area at five sites using
motion sensor camera and at six additional sites via targeted searches (i.e. scats, tracks or dens). To
complement the baseline survey findings, all sites were reassessed during the risk assessment phase
by the WTACS contractor. During this secondary survey, fox evidence was located at Point Resolution,
Bayview, Buckland Hill, Swanbourne and Lake Claremont and these sites were identified as suitable
for trap installation. This proves consistent with data captured during the baseline survey with the
exception of Peasholm Dog Beach where risk was deemed too high for trap deployment. Trapping
locations were identified within four additional reserve sites and 14 traps were installed in total; however,
no foxes were caught during the control phase.
The data provided by the baseline survey suggests that foxes are present in low numbers within the
WESROC Study Area. Despite this, evidence noted during trap inspection suggested foxes were
coming into the immediate proximity of trapping sites. The capture of these individuals was impeded
by specific complexities such as access and trapping site disturbance.
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A key factor limiting the distribution of traps across all the sites surveyed during the baseline survey
was the risk associated with uncontrolled domestic dogs. It was requested that participating councils
inform their patrolling rangers to be vigilant with regard to owners exercising dogs off leash. Throughout
the duration of the control period, dogs were noted running off lead in areas of local council prohibition.
Monument Hill, Mosman Park is one noted example where this problem was particularly prevalent.
Human interaction and disturbance also proved to be a hindrance across numerous sites. At Bayview
Park, danger tape and signage was removed from the immediate trapping area and evidence of
domestic dog presence was identified within close proximity of a set trap (Plate 4). Upon discovery, all
traps at this site were removed.
Plate 4: Image of dog off leash captured during baseline survey – Bayview Park
The occurrence of concurrent environmental projects also resulted in unwanted encroachment at
trapping sites. For example, at Point Resolution a team of Conservation Volunteers collecting seeds
for the City of Nedlands were found wandering through the bushland site oblivious to the presence of
modified jaw traps. Traps were disabled from the site until work completion was confirmed. Similarly,
at the UWA site insect traps were installed within meters of the fox traps. It is well accepted that foxes
can be xenophobic and the trap site should remain as undisturbed as possible.
Notably, a concurrent fox trapping exercise was also operating simultaneously within the WESROC
area. It was noted by the contractor that foxes at both Swanbourne and Lake Claremont took evasive
action to avoid trap sites. The contractor noted that this experience was consistent with previous
observed experiences where foxes had become ‘trap shy’.
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A final limitation relates to the exclusion of access to some sites and of particular concern is the
exclusion from sites of known populations. Bold Park management permitted access for the initial
baseline survey but did not wish to participate in the control phase due to the lengthy permission process
and complexities of risk assessment. Future programs should aim to take the time to navigate this
procedure so access to the largest continual tract of remnant bushland in the WESROC area can be
granted.
Access to Wembley Golf Course was not granted despite the grounds staff acknowledging that foxes
were present and killing native wildlife. The WTACS contractor was informed by staff that foxes are
regarded to be beneficial as they minimise the damage to the golf course caused by birdlife inhabiting
the lakes. Coincidently, during the baseline survey it was reported to GA that two foxes had been found
dead at the golf course. Staff at the site were assured that the causation was not related to GA’s
activities at the time. It is important to note that contrary views exist on fox management within the
WESROC area and could jeopardise the integrity of future control efforts.
Conclusion
Due to the low number of foxes and the high level of interference by public and domestic dogs, it may
be difficult to justify a future large scale fox trapping program; however, it should be noted that individual
foxes can still have an adverse impact on native species and while fox numbers are low local councils
should make an effort to keep numbers down.
A systematic and ongoing monitoring programme would be a suitable method of determining when
foxes have settled into an area could guide when control should be undertaken. Local ‘friends groups’
and the maintenance of an online public sighting register may be useful for ongoing monitoring at a
reasonable cost.
In order to maximise the value for money and ensure the greatest chance of success the councils could
offer further support to future programs by:
undertaking regular ranger patrols before and during trapping events to ensure dogs are kept
under control;
collecting and providing historical spatial data of fox dens etc. prior to commencement of
trapping;
providing access to all reserves in advance of any control efforts; and
providing greater public awareness.
Future Direction
The data obtained from the baseline survey reflects the dominance of introduced and generalist species
in the domestic landscape. The Brown Rat proved to be the species captured most on camera and is
also widely distributed across the WESROC landscape and should be considered when planning future
control efforts.
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Cats pose a significant threat to native wildlife and the data obtained within this survey supports this.
Future control strategies should consider the inclusion of cats as a target species as their abundance
in the landscape appears greater than other predators such as the fox. Cat management would ideally
incorporate both feral and domestic components. Feral cats can be trapped with cage traps and
checked for signs of ownership then taken to a Cat Haven to be rehomed, or euthanized. Domestic
cats may be best managed with several techniques such as:
public education of the threat domestic cats pose to native populations;
enforcing existing laws;
studies of domestic cat use of public bushland;
subsidized sterilisation of cats;
promotion of alternative pets; and
offering subsidies for cat containment.
It should be noted that that studies have shown that removing one predator species from an area can
cause an increase in another as the competition for resources is reduced (ie. meso-predator release).
To ensure a net positive value of predator control, it is recommended that an integrated control
programme be undertaken, including control of both cats and foxes and regular population monitoring.
Rabbit control across multiple jurisdictions requires a timely coordinated approach with agreed access
and control methods. Historical data referring to rabbit habitation was not readily available from
councils, however, this document will provide a baseline for future contractors. A mutual understanding
of the project aims across all stakeholders is essential for maximising control measures through a
uniform approach. For future control works, it would be of significant benefit if permits and access were
granted by all councils and control measures such as baiting could occur across a broader scale.
A more timely and informed planning phase may also allow managers of restricted land to participate
in a project. For example, the baseline survey identified evidence of rabbits at six sites within Bold
Park. Unfortunately, access to these sites was not permitted by the Botanic Gardens and Parks
Authority so no control occurred at this site. These untreated sites jeopardise the long-term outcome
of control efforts as they provide a refuge for target species.
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