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Strategic Red Fox control on bushfire
affected public land in Victoria
Black Saturday Victoria 2009 – Natural values fire recovery program
Alan Robley, Graeme Newell, Matt White, Anna MacDonald, Stephen Sarre,
Barbara Triggs, Janette Currie, Stephen Smith
Strategic Red Fox control on bushfire affected public land in Victoria
Alan Robley, Graeme Newell, Matt White
Arthur Rylah Institute for Environmental Research
Department of Environment and Primary Industries
PO Box 137, Heidelberg, VIC 3084.
Anna MacDonald, Stephen Sarre
Institute for Applied Ecology,
University of Canberra, Canberra,
ACT 2601.
Barbara Triggs
Genoa VIC 3757.
Janette Currie
Parks Victoria
Binns-McCraes Rd,
Alexandra, 3714.
Stephen Smith
Department of Environment and Primary Industries
Binns-McCraes Rd,
Alexandra, 3714.
This project is No. 21 of the program ‘Rebuilding Together’ funded by the
Victorian and Commonwealth governments’ Statewide Bushfire Recovery
Plan, launched October 2009.
Published by the Victorian Government, Department of Environment and Primary
Industries, July 2013.
© The State of Victoria, Department of Environment and Primary Industries 2013.
This publication is copyright. No part may be reproduced by any person except in
accordance with the provision of the Copyright Act 1968.
Authorised by the Victorian Government,
8 Nicholson St, East Melbourne.
Print managed by Finsbury Green.
Printed on recycled paper.
ISBN 978-1-74287-729-7 (print)
ISBN 978-1-74287-730-3 (online)
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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
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Citation: Robley, A., Newell, G., White, M., MacDonald, A., Sarre, S., Triggs, B.
Currie, J. and Smith, S. (2012) Strategic Red Fox control on bushfire affected public
land in Victoria – Black Saturday Victoria 2009 – Natural values fire recovery program.
Department of Environment and Primary Industries, East Melbourne, Victoria.
Front cover photographs: Digital camera monitoring set-up (Jenny Nelson),
Red Fox (Alan Robley), Smoky Mouse (Peter Menkhorst).
i
Contents
Acknowledgements v
Summary vi
1 Introduction 1
1.1 The Black Saturday bushfires 1
1.2 Predator issues following bushfires 1
1.3 The project 2
1.3.1 Project objectives 2
1.3.2 Project components 3
1.3.3 Complementary projects and programs 3
2 Identifying strategic areas for fox control 4
2.1 Introduction 4
2.2 Strategic prioritisation method 4
2.3 Priority locations for Red Fox control and monitoring 7
2.4 Strategic planning discussion 13
3 Field implementation of Red Fox control 14
3.1 Introduction 14
3.2 Field implementation methods 14
3.3 Field implementation results 20
3.4 Field implementation discussion 22
4 Monitoring the effectiveness of the program 24
4.1 Introduction 24
4.2 Monitoring methods 24
4.2.2 Measuring changes in Red Fox populations 24
4.2.3 Capture rates for Red Foxes pre and post predator control 25
4.2.4 Measuring Red Fox diet pre and post baiting 26
4.3 Measuring changes in native species populations 26
4.3.1 Camera capture rate 26
4.3.2 Changes in site occupancy of native species 26
ii
4.4 Monitoring results 27
4.4.1 Changes in Red Fox abundance 27
4.4.2 Food items in Red Fox scats 30
4.4.3 Native species response 31
4.5 Monitoring discussion 34
5 Recommendations 37
6 Beyond this project – a postscript 39
References 40
Appendix 1 Relative ranking of fauna species considered to be at risk from Red Fox predation 42
Appendix 2 Percentage of food items in 80 scats collected from study area 45
Appendix 3 Guidelines for establishing and maintaining Red Fox control bait stations 47
Appendix 4 Sample media release 48
iii
List of tables and figures
Tables
Table 1. Degree of alteration applied to species distribution models in accordance with DSE’s 2009
Fire Severity Class mapping. 4
Table 2. Description of target areas selected for post-fire Red Fox predator control. 14
Table 3. Strategic Red Fox predator control program, summary of operational statistics for areas treated. 15
Table 4. Fox baiting program on-ground results October 2010 to December 2011. 20
Table 5. Four burn categories of fire intensity used to assess distribution of native species across the study area. 24
Table 6. Captures per 100 camera trap nights in four burn categories from the pre-Red Fox control ScoutGuard
and Pixcontroller camera survey. 32
Table 7. Occupancy estimates for species detected during pre- and post-Red Fox control survey. 33
Table 8. Probability of a significant difference between pre- and post-control occupancy estimates. 34
Figures
Figure 1. The 2009 fire-affected areas considered for Red Fox control. 1
Figure 2. Analytical logic used in this investigation. 6
Figure 3a. Outputs of Zonation analysis: rank of all 126 species prior to being altered by the 2009 fires. 7
Figure 3b. Outputs of Zonation analysis: rank of all 126 species not impacted by fire. 8
Figure 4. Comparison of Zonation analysis using ranked and equal rank approaches. 8
Figure 5. Kilmore East-Murrindindi Fire Complex comparisons of pre-fire and post-fire ranked surfaces. 9
Figure 6. Difference between pre-fire and post-fire models shown in Figure 5. 9
Figure 7. Baiting utility study area across fire-affected areas and the hexagon sampling units (10 km2)
aligned with the fire-affected area in the Kilmore East–Murrindindi Fire Complex. 10
Figure 8. Baiting Utility Index displayed across all land tenures. 11
Figure 9. Baiting Utility Index confined to public land. 11
Figure 10. Priority areas for monitoring and evaluating Red Fox control in the Kilmore East-Murrindindi Fire Complex. 12
Figure 11. Area of public land in which Red Fox baits were laid in the Beechworth-Library Road fire area. 15
Figure 12. Area of public land in which Red Fox baits were laid in the East Tyers-Thomson fire area. 16
iv
Figure 13. Area of public land in which Red Fox baits were laid in the Kilmore East-Murrindindi Complex fire area. 17
Figure 14. Area of public land in which Red Fox baits were laid in the Bunyip Ridge Fire area. 18
Figure 15. An example of a mandatory sign to notify that 1080 baiting is in progress – Beechworth fire area. 19
Figure 16. Contractor preparing to bury DeFox bait at a bait station in the Beechworth fire area. 19
Figure 17. Results for bait take per station per week vs time across treated areas. 21
Figure 18. Tasmanian Red Fox scat collecting team. 25
Figure 19. Example of a small and intermediate-sized mammal captured by remote camera. 26
Figure 20. Location of scat collection transects during the pre- and post-Red Fox control surveys in
September and November/December 2010. 27
Figure 21. Predator scats collected showing vary degrees of decomposition 28
Figure 22. Location of Red Fox positive scats pre and post control. 29
Figure 23. Percentage of food items in Red Fox scats pre- and post-control. 30
Figure 24. Percentage of food items in Red Fox scats across fire categories. 30
Figure 25. Location of ScoutGuard digital cameras used in the pre and post-baiting survey. 31
Figure 26. Species captures per 100 camera trap nights in four burn categories from
the pre Red Fox control ScoutGuard and Pixcontroller combined camera survey. 33
Figure 27. Effect size of Red Fox control on occupancy estimates pre and post Red Fox control. 34
v
Acknowledgements
We thank Jenny Nelson, Michael Scroggie and Andrew
Gormley for assistance with the camera survey design and
subsequent analysis and all the members of the Statewide
Natural Values Fire Recovery Implementation Team and
Predator Control Project Control Board; in particular, Craig
Mackenzie (Parks Victoria), Phil Pegler (Parks Victoria) and
Stephen Smith (Department of Environment and Primary
Industries). Dr Atte Moilanen (University of Helsinki) kindly
supplied a 64-bit beta version of the Zonation software to
run the species distribution model analysis.
Our thanks to Janette Currie (Parks Victoria), Felicity Smith
and James Cowell (Department of Environment and Primary
Industries) for support and assistance in the development of
the field monitoring component.
We thank the Tasmania Red Fox scat detector dog team
from the Tasmanian Department of Primary Industries,
Parks, Water and Environment; handler Olivia Barnard
with Tommy and Buddy, and handler David Cunningham
with Bluey and Orange, without whom we would have
found only half the scats we did.
For the on-field implementation component of the project
we thank Craig Mackenzie (Parks Victoria) for Statewide
Project Coordination. Our thanks to the following staff from
Parks Victoria and DEPI for project delivery:
• KilmoreEast-MurrindindiComplexrearea–Janette
Currie, Andy Miller and Mark Mickelburough
• BunyipStateParkBunyipRidgeTrackrearea–Greg
Young, Daniel Bowen and Steven Robertson
• EastTyers-Thomsonrearea–WayneFoon
• Beechworthrearea–JackHarrington(DEPI)andNeil
Wilson (DEPI).
Thanks to Josephine MacHunter and Lindy Lumsden of
the Arthur Rylah Institute and Stephen Platt of DEPI for
comments on earlier drafts of this report. Penny Richards
assisted with collation of field implementation information.
In 2013, the former Department of Sustainability and
Environment (DSE) and Department of Primary Industries
(DPI) became the Department of Environment and Primary
Industries (DEPI). To avoid confusion, this report retains
the names of the former departments where it refers to
arrangements at the time the project was conducted.
vi
Summary
This project aimed to protect and assist recovery of native fauna by reducing the impact of introduced
Red Foxes in fire-affected areas following the 2009 Black Saturday bushfires.
A new evidence-based method for identifying strategic areas for post bushfire, fox control was
developed based on the use of Species Distribution Models and the program Zonation. This process
identified the eastern section of the Kilmore East–Murrindindi Fire Complex as the prime location for
Red Fox control and associated monitoring and evaluation.
Fox control was implemented at four fire areas – Beechworth-Library Road, Kilmore East-Murrindindi,
Bunyip Ridge, East Tyers-Thomson – covering 295,985ha. Some 15,092 baits were deployed at
4,074 bait stations of which 3,094 were taken. Contractors, under supervision, undertook the work
19 months after the fire event.
DNA genotyping was unable to determine the effectiveness of the eight-week fox control program
due to the low sample size (n=55). The overall camera capture rate for Red Foxes increased from 2.2
during the pre-control survey to 8.6 in the post-control survey. The reasons for this are not completely
apparent, however, juvenile animals were observed only during the post-control survey, suggesting that
young dispersing animals may have been exploring the habitat during this phase.
The most common fox prey item was mammalian, comprising Brushtail Possum (Trichosurus sp.42%)
most likely T. cunninghami, followed by Swamp Wallaby (Wallabia bicolor; 14%) and European Rabbit
(Oryctolagus cuniculus; 11%). Birds, insects and plants were also consumed.
The proportional composition of dietary items may not be an indicator of the impact Red Foxes are
having on native species. Species that were rare in Red Fox scats were Feathertail Glider (Acrobates
pygmaeus), Sugar Glider (Petaurus breviceps), Greater Glider (Petauroides volans), Common Ringtail
Possum (Pseudocheirus peregrinus) and Eastern Pygmy-possum (Cercartetus nanus; near threatened).
Post-fire predation in fire impacted habitats may have an important role in the resilience of ecosystems
subjected to fire.
The occurrence and distribution of native species provided baseline data for species considered at risk
from Red Fox predation in the fire-affected areas. We recorded 36 camera detections of 12 species
across four fire severity categories. In proportion to the camera trap nights in each burn category the
majority of captures were within the Severe Scorch category (15.6). In the 100% Burnt and Light Scorch
category camera capture rates were 8.3 and 8.1 respectively and in the Moderate Scorch category
they were 5.2 per 100 camera nights. Only Antechinus spp. and Swamp Wallaby were recorded in the
100% Burnt areas and House Mouse (Mus musculus) was only detected in the Light Scorch areas.
The most commonly captured species on cameras were Swamp Wallaby and Mountain Brushtail
Possum. Wallabies were most often captured by cameras in both the Burnt and Severe Scorch
categories as were Antechinus spp. (both 4.2 and 3.1 captures/100 camera trap nights), while
Mountain Brushtail Possum were most often captured in both the Severe Scorch and Light Scorch
areas equally (2.1 and 2.2 respectively). Bush Rats (Rattus fuscipes) were captured twice as often in
Severe Scorch areas (2.1) in relation to the other categories. The threatened Smoky Mouse (Pseudomys
fumeus) was recorded from only one site, and this was in a Severe Scorch area.
Occupancy estimates were determined for seven species detected by cameras, with the exception of
Echidnas (Tachyglossus aculeatus) for which there were too few encounters. There was a significant
positive effect of Red Fox control on Superb Lyrebirds (Menura novaehollandiae), and a significantly
vii
negative effect on small mammals. There was a substantial, but not statistically significant, decrease in
Feral Cats (Felis catus) post-control.
The ability of the monitoring program to provide robust evidence of a native species’ response
to post-fire Red Fox control was constrained by the reporting timeframe and time-since-fire. The
success of the long-term monitoring program will be determined by the availability of resources
and the ability to obtain additional monitoring from other sources, such as postgraduate studies
at universities. The monitoring program will provide valuable information on the presence and
distribution of a range of native species, and this information enhances our understanding of the
statewide distribution of these species.
Preparedness recommendations
This project has contributed to the knowledge and processes that underpin an enhanced response
to future fire events.
Strategic planning could be enhanced by developing the data sets and information tools necessary to
prepare for future emergency events in which predation may be a significant risk. Forward preparation
of mapped locations for priority control of pest animals, with or without a major disturbance, would
benefit rapid response to emergencies. It would also enable priority areas for predator control to be
targeted prior to the potential negative effects of fire.
Pre fire data on predators and prey populations, and a capacity to rapidly acquire data on predator and
prey populations immediately following fire would be beneficial, including the option of using trained
dogs for scat collection.
As predation is likely to have its most significant effect immediately following a fire event, early access
to funding, even in relatively small amounts, would enhance the capacity for rapid response and more
effective outcomes.
Preparation of standard monitoring and recording systems (e.g. for bait take data) and tools, such as
smartphone applications, would ensure appropriate and comparative data was being recorded across
a wide range of users involved in implementation of predator control programs.
Project recommendations
The following recommendations are made to guide future projects:
Planning – Issues associated with such factors as inclement weather, difficult terrain, poor access and
track conditions, fuel reduction burns, animal behaviour etc. need to be factored in when planning
future fox control programs. Flexibility should be built into the program to cater for these variables.
Document preparation and timing – In planning future programs, required approvals and
documentation (such as the PV/DSE Application to Control Pest Animals documents) should be
obtained well beforehand to avoid delaying commencement of a program.
Risk Identification and Management – Due to the remote and rough nature of the program area,
contractor and supervisor safety needed careful consideration. Potential risks can be mitigated
through the use of well maintained vehicles equipped with UHF and trunk radios, high gain mobile
phone antennas, recovery equipment, first aid, personal locator beacons, personal protective
equipment, etcetera and by way of communication protocols such as checking in and out of areas
viii
by text message and leaving daily route/location details with relevant supervisors and at work centres.
These equipment and procedural requirements should be incorporated into job safety documents.
Communications – As Shire mailout lists will not reach all properties, future projects should
anticipate the need for additional, hand-delivered, landowner notifications. Additional signage and
media would be useful to alert the public to the program and its value. Increased interaction and
engagement with user groups and the community prior to a baiting run to ascertain their recreational
habits and possibly modify the baiting areas would be beneficial.
Use of bait station cameras – More extensive use of remote cameras at selected bait stations would
provide more comprehensive monitoring data, particularly where there is a risk of off-target bait take
to identify species potentially affected.
Ongoing fox control – A fox baiting program should be undertaken over an adequate length of
time to maximise effectiveness and efficiency of the program. The timeframe could be based on the
degree of redevelopment of habitat, which may take 3–5 years depending on vegetation type and
site variables.
Suppression of the Red Fox population – Bait take data should be analysed for each round of
baiting. Mitchell and Balogh (2009) describe methods for converting bait take data into an index of
abundance using frequency/density transformation.
Digital cameras (maximum two per km2 set for a minimum of 21 days using a predator lure) can
also be used to assess trends in occupancy. This approach could also be used to assess trends in
occupancy rates of Feral Cat. It would not be appropriate to use digital cameras for assessing
changes in native species at the same sites as for introduced predators, as this combination would
require luring introduced predators and native species to the same site.
Monitoring changes in predator diet – Continued annual assessment of the proportional
composition of Red Fox diet would provide information on the spatial and temporal change in
distribution of a range of native species that were not detected by camera survey. Scat collection
should occur at the same time and place as in this study.
Monitoring changes in native species – Further interrogation of the model output to identify those
species that comprised the overall biodiversity benefit described in the model. This information could
be used to better target monitoring methods to those species.
Site occupancy may change over years as populations change. When sites are surveyed between
these periods of change, over a number of years, the approach described here can be combined with
a robust mark–recapture approach (Pollock et al. 1990). Sampling, using digital cameras, should be
repeated at the same site each year and continued for several years. The change in occupancy rates
over years could then be modelled as a function of site colonisation and extinction rates, analogous
with birth and death rates in an open-population mark-recapture study, and explanatory variables
such has fire history, presence of predators, and changes in vegetation structure can be incorporated
into the analysis.
While the monitoring and evaluation of selected indicator species has been designed using the best
available data, it is strongly recommended that in future, after the first year, the data collected is used
to reassess the sampling design and, if necessary, amend the monitoring program.
1
1 Introduction
1.1 The Black Saturday bushfires
The Black Saturday bushfires that ignited in Victoria on
7 February 2009 consisted of 14 major fires that burnt
430,000 hectares (Figure 1). Of the area burnt, 69% or
284,510 hectares, is public land of which 25% contains
high biodiversity values protected in conservation reserves
(DSE 2010).
Shortly after the fires, the Department of Sustainability and
Environment (DSE) and Parks Victoria (PV) reviewed existing
data to determine what natural assets and populations
of fauna and flora were at risk. This task identified that
within the area burnt there are 27 Environment Protection
and Biodiversity Conservation Act 1999 listed (nationally
significant) species, and 19 Flora and Fauna Guarantee Act
1988 listed species potentially affected by the fires, along
with numerous threatened ecological communities (e.g. Cool
Temperate Rainforests) and other ecological communities
of concern (e.g. ash eucalypt forests and sub alpine bog
communities). Immediate threats and required actions
to address those threats to these species and ecological
communities were identified by fire area.
1.2 Predator issues following bushfires
The scale and intensity of the Black Saturday bushfires
significantly and directly impacted on populations of fauna
species. Ground dwelling and small arboreal mammals rely
on the under and mid-storey vegetation for shelter and
food. The intensity of the Black Saturday fires removed the
under- and mid-storey layers over large areas of parks and
forest. Consequently, any remaining fauna are forced to
cover greater distances over open ground to find adequate
food and/or shelter, which leaves them vulnerable to
predation by predators such as the introduced Red Fox
Vulpes vulpes. For species already under threat for a variety
of reasons before this fire event, the risk of predation might
mean that local populations of native fauna will not recover.
Immediately following the fires, as soon as human safety in
the fire area could be assured, urgent, small-scale, targeted
predator control was undertaken at several locations —
Kinglake National Park (to protect Brush-tailed Phascogale
Phascogale tapoatafa), Wilsons Promontory (New Holland
Mouse Pseudomys novaehollandiae), Bunyip State Park
(Southern Brown Bandicoot Isoodon obesulus, Swamp
Figure 1. The 2009 fire-affected areas considered for Red Fox control.
2
Antechinus Antechinus minimus) — to protect threatened
species at risk from foxes and cats.
Following the establishment of the recovery program,
and after reviewing previous post-fire predator control
methods, DSE and PV decided to take a strategic approach
to fox control by targeting effort (time, money and other
resources) at locations and species that would yield the
greatest benefit. Priority locations were selected from
a spatial analysis of the distribution of ranked rare or
threatened species and other species considered as being at
risk from fox predation within or adjoining bushfire-affected
public land. This identified and prioritised areas for targeted
control works. This new approach, documented in this
report, is intended to assist future recovery programs.
1.3 The project
The Project, initiated in 2010, was developed within the
program ‘Rebuilding Together’ funded by the Victorian and
Commonwealth governments’ Statewide Bushfire Recovery
Plan, launched October 2009. In line with previous practices,
public land management agencies submitted post 2009 fire
project proposals which included multiple bids related to
predator control programs across bushfire-affected areas in
eastern Victoria. Some proposals included larger aggregated
areas across public land tenures while others were for
smaller areas managed by a single land manager. Instead
of distributing funds based on individual project proposals,
the Statewide Natural Values Fire Recovery Implementation
Team (NVIT) worked with proponents of Red Fox control
to develop a single, cross-tenure project with strategic
components (i.e. this project). A separate project to assess a
bait for Feral Cat Felis catus management was also funded
(Johnston 2012).
The NVIT oversaw all natural recovery projects and regular
progress reporting to the Victorian Bushfire Reconstruction
and Recovery Authority (VBRRA). The NVIT appointed a
multi-agency Predator Project Control Board (PPCB) to
provide governance and technical advice and direction for
this project.
The project was led by Parks Victoria but delivered tenure
blind within bushfire-affected public land managed by
the DSE, PV and Melbourne Water (MW). Project delivery
involved an intensive 1080 fox baiting program, coordinated
across targeted areas. The aim was to reduce predator
populations to a level that enables prey species to increase
their populations and/or distribution back into recovering,
fire-affected habitats. Red Fox control using baiting, was
implemented between early 2010 and December 2011.
The Arthur Rylah Institute for Environmental Research (ARI)
was commissioned to develop an approach for identifying
and selecting sites where investment in post-fire predator
control was most likely to provide the maximum benefits
for biodiversity protection, and to implement a monitoring
program that a) assessed the short term response of
native species to post-fire Red Fox control and b) laid the
foundation for a longer term monitoring program should
further funding become available. Time constraints and
available resources meant that no control sites, where
no fire and/or no Red Fox control were imposed, could
be included for comparison. This limitation, and the
time between the fire event and the commencement
of monitoring (19–20 months post-fire), restricted the
investigation into the impacts of post-fire predation and the
response of native species to Red Fox control.
Following the period of assisted recovery by this project, and
the return of vegetation cover, it is anticipated that predator
control will be delivered through agencies’ ongoing
programs. An example of this is presented in Section 4.
1.3.1 Project objectives
The outcomes sought from the project were:
• Apriorityrankingofeachspeciesatriskbasedontheir
susceptibility to predation by foxes
• Theoccurrenceandmodelledspatialdistributionofthose
species across bushfire-affected public land.
• Thedevelopmentofprioritisedtargetareasforpredator
control treatment based upon species threat assessment,
fire intensity and severity and regional delivery capacities.
• Areductioninpredationpressureonspeciesatrisk
from predation and including mammal, bird, reptile and
amphibian species in the fire-affected areas, allowing for
the recovery of these pre-fire occurring species.
• Thedevelopmentofappropriateandconsistently
implemented standards relating to pest predator control
monitoring protocols and reporting procedures.
• Animprovedunderstandingoftheeffectivenessofpost-
fire pest animal control on predator populations.
• Animprovedunderstandingofthepost-rerecoveryof
threatened mammal populations.
• Theidenticationoflinksandthedevelopmentof
management delivery efficiencies with the Fire Recovery
Pest Plant Control Project and researchers on other pest
animal programs such as the Southern Ark, Glenelg Ark
and Otway’s pest animal research program.
• Theprovisionofaccuratedataandmappinginformation
with an integrated mapping and data capture system
to ensure accuracy, consistency and portability between
agencies for all spatial information.
• Tocontributetocommunityrecoverythrough
employment opportunities and increased community
engagement in, and understanding of, pest animal and
threatened species control and monitoring programs.
3
1.3.2 Project components
The project consisted of three key components:
• Developmentofanewmethodforidentifyingstrategic
areas for fox control
• FieldimplementationofRedFoxcontrol
• Monitoringoftheeffectivenessoftheprogram.
1.3.3 Complementary projects and programs
In addition to this project, other predator control projects
across bushfire-affected public land areas were being
implemented. Where possible, projects were integrated,
particularly when Red Fox was a priority for other projects.
The Australian Government’s Caring for our Country (CFoC)
funded projects had some overlap but also involved wild
dog control and control methods other than baiting. A Red
Fox control project associated with environmental offsets for
the Sugarloaf Pipeline in the Toolangi area was integrated
into the field delivery of this project.
4
2 Identifying strategic areas for fox control
2.1 Introduction
The strategic planning component of this project aimed
to develop an evidence-based, tenure-blind approach to
identifying areas that should be targeted for predator
control following bushfire. Effective fox control depends
on large-scale, frequently-applied baiting, so the project
sought to identify large areas where multiple assets could
be protected. It also aimed to identify specific sites for
monitoring and evaluation.
Strategic planning and monitoring components of
the project were led by the Arthur Rylah Institute. The
outcome was a series of mapped outputs that provide
decision-support capabilities to targeted Red Fox control
in fire-affected areas.
2.2 Strategic prioritisation method
Selecting Species Distribution Models
A series of systematic and statistically robust methods for
producing and evaluating ‘mapped’ probabilistic Species
Distribution Models (SDMs) for native fauna had previously
been developed by the Spatial Ecology Group (G. Newell
unpub. data) of the Arthur Rylah Institute. These SDMs
were developed using location data from the Victorian
Government’s biodiversity databases.
From all known mammal, bird and reptile species that
occur in Victoria, 126 species were selected for inclusion
in the assessment of priority Red Fox control areas. Species
that were omitted from the analysis were those for which
reliable SDMs could not be produced for various reasons
(e.g. data quality, water birds, species at the edge of their
distributional ranges, migratory species with poorly defined
habitats). A list of all species considered, along with their
estimated risk of Red Fox predation as previously defined by
Robley and Choquenot (2002), is provided in Appendix 1.
The SDMs in their native form are at a resolution of 25 m,
but that was considered too fine a scale for this investigation.
Consequently, all SDMs were resampled at 100 m resolution,
with an extent covering the whole of Victoria.
Bushfire severity mapping
Following the 2009 bushfires, DSE developed a fire severity
model from remotely sensed imagery, reflecting the degree
of crown and understorey damage on an eight-point scale
(Table 1). The modelled surface produced was used to
differentially model the likely reduction in the probability of
species distribution to the SDMs according to the weightings
shown in Table 1. The degree of alteration applied to species
distribution was set by consensus with the Predator Project
Control Board and fauna experts from ARI.
Table 1. Degree of alteration applied to species distribution models in accordance with DSE’s 2009 Fire Severity Class mapping.
Fire
Severity
Class
Description Alteration
level to
SDMs (%)
1 Crown burn 70–100% crowns burnt in an intense overstorey burn with widespread crown
removal and 100% understorey removed.
100
2 Crown scorch 60–100 % crowns scorched, some crowns are burnt an intense understorey fore
with complete crown scorch of most tree and tall shrubs.
90
3 Moderate crown scorch 30–65% crowns scorched a variable intensity fire from warm ground
burn with no crown scorch to an intense understorey fire with complete crown scorch of most
tress and tall shrubs.
80
4/5a Light or no crown scorch; understorey burnt 1–35% of crowns scorched, a light ground burn
with patches of intense understorey fore, some crown scorch. May include areas of unburnt
forest.
70
5b No crown scorch; no understorey burnt <1% of crown scorched. 0
6 Burnt woodlands, unclassified. 80
7 Burnt grasslands. 80
8 Unburnt grasslands. 0
5
SDMs for the target species were assembled in two ‘stacks’
— one stack was the pre-fire or un-impacted state, and in
the other stack each SDM model had the modelled damage
applied.
Zonation software
The 126 SDMs were integrated in a spatial optimisation
using Zonation, a free software program for spatial
conservation prioritisation (University of Helsinki 2010).
Zonation effectively addresses the problem of assessing
‘maximum utility’, taking into account distributions of
biodiversity features, connectivity responses, priorities for
features, and a variable emphasis on highest local quality.
The main output of a Zonation analysis is a hierarchical
ranking of priority for all cells in the landscape, which can
be visualised as zoned maps.
The Zonation process determines the optimal sites for
the conservation of the target species before the 2009
fires and compares this result with the areas impacted by
the 2009 fires. The Zonation procedure sequentially and
iteratively removes cells that are least important in the
intersection of all of the spatial inputs in each analytical
stack independently. All analyses used a ‘warp factor’ (the
number of cells removed at each iteration) of 1000, so
that a total area of 1,000 ha was removed across Victoria
at each iteration. At this setting, each species model run
took between 60 and 70 hours to complete. The size of the
calculation involved (i.e. 126 species at 100 m resolution,
with 8,136 columns × 5,771 rows = 4.7 ×107 cells per SDM)
required a 64-bit beta version of the software that could run
under Microsoft Windows 7. This version of the software
was supplied directly by Dr Atte Moilanen (Academy
Research Fellow, Vice-director of the Metapopulation
Research Group, University of Helsinki).
The overall logic of the analytical approach in this study
is shown in graphical form in Figure 2. For the pre-fire
state, Zonation was used to produce a ranked surface of
the biodiversity values across a landscape, which can be
viewed as a ‘map’ and a cross-sectional ‘profile’ (Figure 2a).
Similarly, a ranked surface can be developed using fire-
impacted SDMs, and the difference between the pre-fire
and post-fire ranked surfaces, can be calculated (Figures 2b
and 2c). A further analysis that was developed during this
study was to investigate the differences across the zones
that were, and were not, directly impacted by the fires.
Figure 2d represents baiting zones applied as a sampling
approach across the landscape to calculate a Baiting
Utility Index.
6
Figure 2. Analytical logic used in this investigation. (a) pre-fire ranked surface and profile of target fauna distribution, (b)
difference calculated by comparing pre-fire and post-fire rank analyses, (c) scores differences shown in profile, (d) application
of baiting efficiency units across both burnt and unburnt landscapes to calculate an index. High values represent higher species
‘richness’.
a
b
c
d
AB
High
Low
AB
High
Low
Fire
AB
High
Low
Fire
Fox
Control
Zonation Ranking
Pre-fire values
AB
Zonation Ranking
Pre-fire values
Post-fire values
AB
Zonation Ranking
Pre-fire values
Post-fire values
AB
–=
Pre-fire Post-fire delta (difference between
pre-fire and post-fire,
e.g. area lost to species)
7
2.3 Priority locations for Red Fox control and
monitoring
The results of the Zonation analyses are shown in Figure 3a,
which illustrates the statewide ranking of the 126 SDMs
when all the species’ distributions are weighted equally. This
result can be compared with the same analysis when the
ranking from Appendix 1 is applied (Figure 3b). There is little
obvious difference when viewed using 10 value classes at
the statewide scale, or at more localised scales such as that
shown to the east of Melbourne, encompassing the Kilmore
East–Murrindindi Fire Complex (Figure 4). For consistency, all
subsequent comparisons between model outputs are shown
using the ranked species approach.
Figure 5 compares Zonation outputs for pre-fire and
post-fire analyses. This comparison highlights that, while
significant areas of high value locations for the suite of
species considered in this study were impacted by fire, there
are also many highly ranked locations immediately outside
the fire-affected areas. This suggests that the interface
between these areas may warrant a high priority for
predator control efforts. Although Figure 8 only shows the
area around the Murrindindi–Kilmore fire area, the analyses
were conducted on a statewide basis to enable comparisons
systematically between each of the fire areas as well as
within individual fire zones. The full comparison is omitted
here for the sake of brevity.
Figure 6 shows the difference between pre and post-fire
models using the same analytical approach (i.e. weighted
SDMs impacted by fire, or not).
Figure 3a. Outputs of Zonation analysis: rank of all 126 species prior to being altered by the 2009 fires. All SDMs are weighted
equally, and data are grouped into 10 classes.
8
Figure 3b. Outputs of Zonation analysis: rank of all 126 species not impacted by fire. SDMs are weighted according to the
schedule in Appendix 1.
Figure 4. Comparison of Zonation analysis using ranked and equal rank approaches.
Weighted Equally Weighted according to Appendix 1
9
Figure 5. Kilmore East-Murrindindi Fire Complex comparisons of pre-fire and post-fire ranked surfaces.
Pre-fire
Post-fire
Figure 6. Difference between pre-fire and post-fire models shown in Figure 5. Darker areas highlight areas of greatest impact.
Difference in fire
impact on fauna
distributions.
10
The next part of the analysis considered not only how the
SDMs within the fire area were directly impacted, but also
considered that these areas were likely to be recolonised
from adjacent unburnt areas. It was recognised that
although Red Fox control is focused on areas that are
directly impacted by the fires, it is also important to provide
support, in terms of Red Fox control, to adjacent extant
populations. In this case we were interested in analysing
priorities not just within the fire area (i.e. the difference
between pre-fire and post-fire analyses) but also across the
fire boundary, to include areas that had been impacted by
fire and areas that would revegetate over a period of time,
and the adjacent localities that are the most likely sources of
recolonisation.
Investigating the ranked priority across the fire boundary
required an estimate of the Red Fox control baiting area.
For this study we estimated the area of influence of an
individual Red Fox control zone to be 10 km2. This is shown
diagrammatically in Figure 2d, where a sampling unit is
placed across the landscape. Hexagonal areas rather than
circular were used to maximise packing efficiency and
spatial geo-processing analyses. These sampling units were
used to cover all areas impacted by the 2009 fires and
buffered by 10 km (Figure 7) to calculate a baiting utility
index.
The Baiting Utility Index was calculated for each hexagonal
10 km2 window using the formula:
Baiting Utility Index = maximum range of difference
between pre-fire and post-fire analyses × mean pre-fire
weighting.
The output from this calculation is shown in Figure 8 for all
tenures and in Figure 9 where areas that are predominantly
private estate are removed from further consideration.
The outputs shown in Figure 8 were then available for a
subsequent investigation of how these priority areas that
have been identified (1) align with the location of previously
used bait stations, and (2) access and practicality issues such
as the location of roads and access tracks.
Figure 7. Baiting utility study area across fire-affected areas and the hexagon sampling units (10 km2) aligned with the fire-
affected area in the Kilmore East–Murrindindi Fire Complex.
11
Figure 8. Baiting Utility Index displayed across all land tenures.
Figure 9. Baiting Utility Index confined to public land. Areas on private land or where 10km2 hexagon
falls mainly on private land is shaded black.
12
Figure 10. Priority areas for monitoring and evaluating Red Fox control in the Kilmore East-Murrindindi Fire Complex. Yellow
dots represent individual monitoring sites.
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Land Tenure
Parks and Reserves Lake Eildon Monitoring Sites Low
State Forest Softwood High
N 0 9 18 km
Baiting Utility Index
Areas where Red Fox control and monitoring would be
implemented within the zoned map were then defined
by the Predator Project Control Board and regional land
management staff. The process of site selection considered
practical issues of access, resource capacity and the spatial
scale at which Red Fox control could be implemented
effectively. Large-scale, frequently-repeated baiting
programs are needed to effectively reduce fox numbers.
Other Red Fox control activities, funded under the Caring
for Our Country Bushfire Recovery program and regional
DSE, Parks Victoria and Melbourne Water initiatives,
were also considered when selecting the monitoring and
evaluation sites. This process identified the eastern section
of the Kilmore East–Murrindindi Fire Complex as the prime
location for Red Fox control and monitoring.
High value BUI hexagons along with the following criteria
were used to determine treatment extent within the
selected prioritised areas.
• Thesizeofthemodelledtargetarea – The minimum
target area chosen for effective treatment was 10,000
hectares. Potential fox control areas less than 10,000
hectares or geographically isolated areas, or areas with
delivery issues associated with access, topography or other
difficulties, were excluded from treatment.
• Capacitytodeliver – Public land management agencies
had varying capacity to deliver in different circumstances
or to deliver particular project components.
• Access – Seasonal restrictions applied to some areas as
a result of seasonal road closures. In some areas road
coverage and road conditions were considered.
13
• Highvisitationorrecreationalactivitynodes,
townships or housing – Baiting was generally excluded
from these areas and buffers applied.
• Pre-existingandalternativefundingarrangements
for predator control project delivery.
As a result of these analyses and practical considerations,
Red Fox control was implemented at four fire areas –
Beechworth, Kilmore East-Murrindindi, Bunyip Ridge and
East Tyers-Thomson – covering 295,985 ha.
The individual monitoring sites within the selected area for
monitoring and evaluation are indicated by yellow dots in
Figure 10. At each of the 40 monitoring locations, a fire
severity score was recorded (Table 5, p24).
2.4 Strategic planning discussion
The process applied here – using spatially ranked
aggregations of SDMs to inform management – is one that
has only been used sparingly in the past. This is primarily
due to a limited number or lack of useful SDMs and a lack
of appropriate software to handle the complexities of spatial
optimisation of such data. To our knowledge, this is the first
time that such an approach has been applied to prioritising
predator control actions after bushfire, and certainly in an
exercise that has been undertaken systematically at a state-
wide scale and for a large number of susceptible species.
An approach that is transparent and allowed managers to
make decisions on where to allocate limited resources and
focus monitoring and evaluation activities was developed
and implemented.
While this approach is unique in its scale, breadth and
systematic approach, it does involve the following
assumptions, limitations and caveats:
• Theprimarycontrastbeingmadeisbetweenapre-re
and post-fire stack of 126 SDMs. This ignores any earlier
fire history and includes species that do not occur in the
bushfire-affected areas.
• Thenativespeciesmonitoringwasfocusedonmammal
species, while the complete stack of 126 species in the
SDMs included birds, reptiles and amphibians at risk from
fox predation. Thus, site selection for fox control may
have been driven by the presence of other vulnerable
species rather than mammals.
• AlthoughtheSDMshavebeendevelopedusinga
systematic approach, they all use a generic set of
predictor variables and are therefore not finely tuned for
each species. SDMs that include refinements may have
advantages in future studies.
• TheassumptionisthatintheSevereScorchcategory,
which represents 70–100% of crowns burnt in an
intense overstorey burn, with widespread crown removal
and 100% understorey removed, and that all individuals
of all species are killed, may not be true in all cases. This
represents a conservative approach to altering the species
distribution after a fire event.
• Theassumptionofa10km2 area as an effective Red Fox
control zone may or may not be appropriate (i.e. it was
an arbitrary decision made in the absence of data), and
future research may refine the control area.
• Intheabsenceofawell-resolvedRedFoxSDMto
represent a constraint surface, an even level of impact
of Red Foxes across all of the Victorian landscape was
assumed. However, this is almost certainly untrue. Future
improvements in a Red Fox SDM could greatly improve
analyses such as this.
Outputs from the Zonation analyses are focused on species’
complementarity (i.e. combinations of species in space), and
not necessarily species’ richness at any location. Although
analyses using the same 126 SDMs with a goal of maximum
species’ richness would probably provide a slightly different
series of outputs, we believe the rank surface output would
be quite similar to that developed here.
Furthermore, although Zonation analysis has involved a
systematic approach to defining localities for optimum
predator control efforts, the final part of the analysis that
would consider the optimal positioning of individual bait
stations has not been described here. Field site selection
should consider access via roads and tracks, distance
from these access routes from which bait stations could
be placed, local tenure issues (i.e. zonation analysis does
not consider different categories and land management
activities by different government agencies), efficacy of
baiting techniques in different habitats, etc.
The analysis undertaken in this project constitutes a
systematic assessment of the likely benefits of predator
control at any particular location within the general areas
impacted by the 2009 fires. The systematic process that
has been developed and applied here may be useful in
addressing similar questions and needs in the future.
14
3.1 Introduction
Following the development of the spatial analysis for predator
control prioritisation using the Species Distribution Models
(SDM), as outlined in section 2.2, the Predator Project Control
Board selected bushfire-affected areas for fox control based
on an Index of values and risk (see section 2.3), practicality
and relationship to other fox control activities.
Parks Victoria led on ground project implementation in all
areas except Beechworth-Library Road, which was led by
DSE. Intensive 1080 fox baiting was used across targeted
areas within bushfire-affected public land managed by the
Department of Sustainability and Environment (DSE), Parks
Victoria (PV) and Melbourne Water (MW). Areas selected
for control are listed in Table 2. Baiting occurred on burnt as
well as adjacent unburnt land.
The on-ground delivery (baiting) for this project occurred
between October 2010 and December 2011. In the Kilmore
East-Murrindindi Complex, this project worked in conjunction
with a Caring for Our Country (CfoC) predator control project
which commenced post-fire in 2009–10. Integrating the two
programs resulted in baiting over a longer time period and
enabled protection over a larger treatment area.
3.2 Field implementation methods
Pre-prepared baits (‘Fox off’ or ‘De-Fox’) containing 3 mg
of Sodium Monofluoroacetate (1080) were buried to a
minimum depth of 100 mm within sand pads, to reduce
the likelihood of non target bait takes and to facilitate
monitoring. These pads were established at intervals of
approximately one kilometre.
Program managers complied with the legislative
requirements for 1080 baiting specified in the DPI Standard
Operating Procedures & Directions for Use document (DPI
2010). This specifies requirements for bait supply, handling,
record keeping, neighbour notifications, signage (Figure
15), bait placement and replacement (Figure 16), risk
assessment, disposal and incident response. In addition,
PV and DSE completed and had approved ‘Application to
Control Pest Animals’ documents.
Due to the often remote and rough terrain, careful planning
for risk management and occupational health and safety
needs for area staff and contractors was undertaken.
Local contractors were engaged to undertake the baiting
programs in each fire area. All contractors were required to
operate in accordance with the Agricultural and Veterinary
Chemical (Control of Use) Act 1992 and hold a Commercial
Operators Licence with a vermin endorsement or a Licence
to use Pesticides.
Guidelines to establish bait stations (see Appendix 3), were
followed by contractors while undertaking the project.
The areas baited within and adjacent to fire areas are shown
in Figures 11–14. Table 3 summarises the baiting program
within each fire area.
3 Field implementation of Red Fox control
Table 2. Description of target areas selected for post-fire Red Fox predator control. SF = State Forest, NP = National Park,
SP = State Park, RP = Regional Park.
Bushfire-affected Areas
targeted for Red Fox
control
On ground
delivery
lead agency
PV Land units
treated
DSE land units
treated
Area burnt
Total (ha)
Area public
land (ha)
Beechworth-Library Rd DSE Mt. Stanley Scenic
Reserve
Stanley SF
Wooragee SF
33,830 21,400
Kilmore East-Murrindindi
Complex
PV Lake Eildon NP,
Cathedral Range SP,
Yarra Ranges NP
Big River SF, Rubicon SF,
Marysville SF, Toolangi
SF, Upper Yarra SF,
Pauls Range SF.
293,925 193,470
Bunyip Ridge PV Bunyip SP, Kurth Kiln
RP.
Yarra SF, Tarrango SF 26,440 18,900
East Tyers-Thomson PV Baw Baw NP,
Moondarra SP.
Tanjil SF, Thomson SF. 1,780 1,780
15
Table 3. Strategic Red Fox predator control program, summary of operational statistics for areas treated.
Operational statistics summary - October 2011– Dec 2012
Bushfire-affected Area Total Area
treated
(hectares)
No. bait runs/
management
zones
Area of bait runs
(range)
No. of pulse
treatments
delivered
Pulse
duration
Beechworth-Library Road 4200 2 1,400–2,200ha 1 36 weeks
Kilmore East-Murrindindi Complex 153,000 6 15,000–30,000ha 4 7–8weeks
Bunyip Ridge 40,985 3 11,000–16,500ha 3 5 weeks
East Tyers-Thomson 30,000 2 15,000ha 3 6 weeks
TOTAL 228,185ha 12 1400–30000ha av. 6weeks
Figure 11. Area of public land in which Red Fox baits were laid in the Beechworth-Library Road fire area.
16
Figure 12. Area of public land in which Red Fox baits were laid in the East Tyers-Thomson fire area.
17
Figure 13. Area of public land in which Red Fox baits were laid in the Kilmore East –Murrindindi Complex fire area.
18
Figure 14. Area of public land in which Red Fox baits were laid in the Bunyip Ridge Fire area.
19
Figure 15. An example of a mandatory sign to notify that 1080 baiting is in progress – Beechworth fire area.
Figure 16. Contractor preparing to bury DeFox bait at a bait station in the Beechworth fire area.
20
3.3 Field implementation results
Bait stations
The fox control baiting program ran across the four selected
fire areas with the following results:
• 1,467baitstationswereestablished(Table4)and
serviced across 295,985 ha.
• 3,094baittakeswererecordedfromatotalof15,092
baits laid (Table 4).
Bait take
A reduction in rate of bait take is expected if predator
numbers decline over time.
Bait take data from each of the four areas was standardised
to bait take per bait station per week to determine rate of
change of bait take and to provide a comparison across
treatment areas (Figure 17).
Bait take data used is ‘all baits taken’. The attribution of
bait takes to Red Fox was inconsistent within and across
areas so was not used to measure change in rate of take.
For example, in Bunyip fire area all bait takes were allocated
to either Dog (wild dogs inhabit the forested areas) or Fox.
Percentage of baits taken that were attributed to Red Fox
ranged from 61% to 73% across three pulses with an
average of 73%. At Tyers-Thompson fire area, bait takes
attributed to Red Fox averaged 52%, with 32% attributed
to Dogs and 16% to other or unknown species. Most (98%)
of bait takes were attributed to Red Fox at Beechworth
and none to Dogs, although Dog footprints were noted
near bait stations. No species were allocated for part of the
program.
Rate of bait take, graphed in Figure 17, shows that there
was no clear decrease in rate of bait take during the baiting
program across the areas treated.
Table 4. Fox baiting program on-ground results October 2010 to December 2011.
Bushfire-affected Area Total Area
treated
(hectares)
Bait stations Total number
baits laid
Total number
of baits taken
Beechworth-Library Road 4200 60 732 255
Kilmore East-Murrindindi Complex *153,000 866 #11,431 2,074
Bunyip Ridge ** 40,985 460 2,718 634
East Tyers-Thomson 30,000 150 211 131
TOTAL 228,185 1,536 15,092 3,094
* This area included Yarra Ranges and Lake Eildon National Parks, Cathedral Range State Park; Big River, Marysville, Rubicon, Toolangi,
Paul’s Range and Yarra State Forest and Melbourne Water’s closed catchments of Maroondah, Cement Creek, O’Shannassy, Armstrong
and Upper Yarra as well as the Sugarloaf Pipeline.
** This area included: Bunyip State Park, Kurth Kiln Regional Park, Yarra and Tarago State Forests. Total area was broken down into three
areas – Area 1 – 11,020ha, Area 2 – 16,500ha and Area 3 – 13,465ha.
# Bait stations were re-established for each pulse treatment and were placed at or near the previous location.
21
Figure 17. Results for bait take per station per week vs time across treated areas. Bait takes are for all baits taken which
includes take by foxes, dogs and other species.
Bait take per station per week vs Time (weeks)
Time (weeks) – week 1 = 4/10/2010
Bait take/station/week
Beechworth
K-M runs 1, 2 & 3
K-M runs 4, 5 & 6
Bunyip
Thomspson-Tyers
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61
Employment
The project engaged local contractors to deliver the field
component of the project. Twenty one contractors and
staff were engaged. Local contractors had local knowledge
and experience of the terrain and methods required for
delivery of the field work. In addition, it was hoped that
the employment of local people would be a positive
contribution to community recovery in fire affected areas.
Communication and community engagement
The project contained plans for communication and
community engagement. Elements of the plan included:
Neighbour notification – mandatory neighbour
notification forms were mailed out and public notices were
also placed in local newspapers.
Media articles – were prepared and sent to regional and
local newspapers. Articles on the Beechworth program were
run in the Border Mail, The Ovens and Murray Advertiser
and The Country News. See Appendix 4 for an example of a
Media Release.
Radio – coverage was obtained in the Beechworth fire area.
Community consultation – in the Bunyip fire area,
community consultation was undertaken in two areas half
way through the program. This resulted in changes to
baiting areas, as the original sites were very close to a rural
community. These changes assisted in increased protection
of domestic animals that led to greater respect from local
residents for the baiting program. In the Beechworth fire
area, all the Landcare Groups and Wildlife Shelters were
informed of the program and they were all supportive of the
project. In Stanley (Beechworth area), baits were removed
for a three week period over the Christmas/New Year period
to accommodate the influx of tourists into the area. This
resulted in the program receiving positive feedback from the
community of Stanley.
A number of other community engagement activities
were held as part of the overall fire recovery program that
included information on the fox control program. They
included various group presentations, YMCA youth days,
a music festival, fire recovery meetings and a tour by a
Catchment Management Authority board.
Interagency liaison and contractor communication
– due to the broad geographical scope and cross-tenure
nature of the program, establishing and maintaining
good inter-agency communication channels was vital to
the smooth running of the program. Within each project
area communication channels were well established and
maintained between PV staff and relevant staff in DSE,
MW, DPI, local shires, catchment management authorities,
etc. This provided for a good two way flow of information
regarding site access, program requirements and successes,
local knowledge, use of equipment etc. In one project area,
the project officer felt they could have benefitted from more
22
interaction with the other project officers working on the
same program in the other fire areas.
Communication was made twice a day with contractors
in regards to safety and duty of care, and de-briefs were
carried out with contractors at the end of each pulse
run. Continual communication with contractors allowed
opportunities to adapt the program and discuss methods for
continual improvement.
Communication with the public – neighbours and the
general public were informed via:
• mail-dropsbeforeeachpulsecontainingtherequired
1080 notification, as well as additional program
information sheets and map
• newspaperadvertisementsadvisingoftheprogramprior
to each pulse; required 1080 signage was placed at all
tracks leading into baiting areas; information sheets and
maps were placed at strategic locations
• informationsheetswerehandedouttoresidents,
campers, etc. as required. In addition, affected user
groups, such as hound hunters, were kept directly
informed through their relevant member associations.
Most comments on the program were positive and
supportive suggesting that the comprehensive approach
to communication was successful in informing the
public. There was very little public concern received by PV
regarding the program
3.4 Field implementation discussion
The impact of baiting on Red Fox numbers is difficult to
measure from the data collected from bait stations. Due
to the variability of data collected, only data standardised
to show bait-take (for all takes regardless of species) per
station per week could be used. Section 4.5 discusses results
of monitoring changes in Red Fox abundance within a
designated area of the Kilmore-Murrindindi fire area using
different methods. That monitoring suggests that Red Fox
abundance may have increased during the program and
gives possible reasons. Likewise, the standardised data from
all areas treated is also inconclusive. Change in rate of bait
take increased from the beginning of baiting to the end at
all except one of five areas (Kilmore-Murrindindi was divided
into two treatment areas) (see Figure 17). Only Kilmore-
Murrindindi runs 1, 2 & 3 had a lower rate of take on the
last pulse compared with the first. At Bunyip and Thompson-
Tyers, rate of take increased across the three baiting pulses
conducted at each area. Beechworth was baited continuously
and the graph shows the variability week to week but the
trend was an increase in rate of take from the beginning to
the end of baiting. Anecdotal reports in the Beechworth-
Library Road fox baiting area suggested that fox sightings
declined toward the end of the baiting period and local
residents reported that native wildlife numbers appeared to
be on the increase (Jack Harrington pers. comm.). However,
the rate of bait take over the program actually rose (Figure
17). There may not be a direct correlation between rate of
bait take and abundance due to factors such as avoidance
behaviour of individual animals and/or bait caching behaviour.
Baiting pulse frequency and duration varied across the
treatment areas and the only continuous treatment was at
Beechworth with a duration of 36 weeks. Robley (2008)
reports that continuous, annual baiting programs showed
substantial reductions in bait-take and some pulsed baiting
programs also showed overall decline in bait-take. A seasonal
baiting program was not able to reduce or maintain a
reduced level of bait-take or fox activity from year to year.
Whist this project strategically selected areas for treatment,
ideally, it is assumed that the baiting program would have
had the greatest effect if the frequency of baiting was more
consistent and the duration of baiting was longer. A Red
Fox control program which commenced following the fire
recovery project (Central Highlands Ark, see section 6), and
which overlaps with the Kilmore-Murrindindi fire area treated
under this project, has enabled this to occur at this location.
Other control methods (e.g. soft jaw trapping) were
employed in some areas (e.g. parts of Bunyip and Kilmore-
Murrindindi areas) to control foxes post-fire, but prior to
and concurrent with this project. Reliance on a single tactic
will have limited success in reducing target species and
consideration should be given to alternative tactics to control
foxes over large areas and long periods (Robley 2008). It is
likely that the effects of this project, in reducing fox numbers
and predation pressure on ‘at risk’ native species during the
early stages of vegetation recovery could have been greater
if the baiting program had started earlier and run more
consistently, for longer and with stronger overlap with other
control measures such as shooting and trapping.
Across the four Red Fox control program areas the following
issues, that affected the delivery of the program, were
identified by field staff and contractors:
Weather conditions – A higher than average rainfall during
the 2010/2011 period made access to bait runs difficult
and at times impossible. In the Kilmore East-Murrindindi
fire area the steep nature of much of the country, and
condition of some tracks, required care to be taken in
order to limit track damage and to ensure safe travel. In
addition, reasonably heavy snowfalls occurred from April
through June, further restricting access and burying bait
stations. In all program areas the variation in weather
conditions (including snow and extreme rain) presented
daily challenges that were dealt with as required.
Terrain – In many of the fire areas, the fox control program
was executed in mountainous country, which in parts was
quite steep, rough and remote. This posed challenges
for access, as well as making in-field communications
difficult at times. In the Kilmore East-Murrindindi fire area,
for OH&S reasons, contractors carried personal locater
beacons and texted their time in and out of the bush, as
23
well as planned route, to the program supervisor. Mobile
phones and UHF radios were also carried but their use
was greatly restricted by the terrain. The track conditions
were at times challenging with all contractors experiencing
some level of damage to vehicles as well as delay from
obstructions such as trees down, rock slides and tracks
impassable due to rain or snow.
In planning routes, good local knowledge and/or field
reconnaissance was required as maps were inaccurate
and some information indicated on maps could not be
relied upon (e.g. to still be in existence, open, maintained).
The presence of log truck traffic on many roads and
tracks leading to, from and through much of the baiting
area, was also an issue of concern for safe travel that
was only partly alleviated by defensive driving and UHF
communications with the log truck drivers.
Track closures – Track closures due to logging activities
and scheduled road works occurred during the course of
the program. These closures required flexibility in route
planning and had the potential to result in an inability to
cover all areas evenly and require more time to complete
runs due to less circuitous routes. Between late Autumn
and late Spring most Melbourne Water catchment roads
are permanently closed to all vehicles by way of concrete
barriers. This delayed works during this period and
required additional negotiation with land managers to
maintain access as well as modified routes. Other seasonal
track closures (typically June to November) also needed to
be considered in program and route planning.
Fuel reduction burns – A number of fuel reduction burns
were scheduled to occur in the baiting areas. These had
the potential to disrupt the program in terms of access,
routes and animal behaviour, as well as considering
contractor safety issues. In the Kilmore East-Murrindindi
fire area only one burn took place because of the wet
conditions.
Sand pad monitoring – In the Kilmore East-Murrindindi
fire area the wet conditions had a major impact on sand
pad monitoring. Contractors were less able to accurately
identify species’ prints in rain-affected sand. Target animal
behaviour may also have been influenced by the wet
conditions.
Public land user groups – Consideration and mitigation of
the potential impact of the baiting program on various
public land user groups was an important consideration in
the planning and execution of the program. A key issue
was the presence of domestic dogs being walked, taken
camping or used as scent trailing hounds in many areas of
State Forest where the baiting programs took place.
Domestic dogs – In the Kilmore East-Murrindindi fire area
there was one official report of a domestic dog death
potentially linked to the program. However, a subsequent
Department of Primary Industries (DPI) investigation
concluded that 1080 bait-take was highly unlikely to have
been the cause of death and that in all ways the program
was highly compliant with required processes. In the
Bunyip fire area, the response to a suspected domestic
dog bait-take was actioned quickly and thoroughly and
the dog survived. The cause of the dog’s illness was not
established but it is doubtful that a poison bait was taken
by the dog.
The comprehensive approach to communications, along
with care in bait placement (large buffer from campsites,
scheduling program around busy periods, etc), helped to
alleviate the potential risks to domestic pets of other user
groups.
Some of the areas of public land where the fox control
program occurred are popular areas for deer hunting (both
stalking and hound hunting). In the East Tyres/Thomson
fire area, Parks Victoria was proactive in notifying the
Australian Deer Association (via their Gippsland branch)
and the Victorian Hound Hunting Association. The
Australian Deer Association was very happy that they were
included in the planning and were able to distribute maps
and information to their members. Hunters were directed
to areas not being targeted by the project.
Time constraints – In most of the fire areas, the length
of time taken to obtain the necessary approvals and
documentation caused delays to the start of the baiting
program. In the Beechworth fire area, the delays proved
frustrating for agency staff and the contractors who had
begun mapping and GPSing the bait station sites as early
as two months before baits could be laid.
The fox baiting program required a substantial amount of
time for planning and set up in each of the four fire areas.
Delays in staff coming on board, and the amount of pre-
planning time required, delayed the commencement of
the program in some areas.
Seasonal issues and the identification of risk – A
continuous nine month program meant that it operated
across each climatic season. This has implications for
weather, fire risk, animal behaviour, public presence/use,
baiting effectiveness and encountering other potential
risk factors such as snakebite and dangers due to heat or
ice and snow. Such issues are clearly out of direct control,
but must be considered in Risk Management plans and
contingencies for these risk factors identified in the
planning and delivery of the program.
Length of the program – As there were delays to the start
of the program, the overall length of the baiting program
(average of nine months) was too short.
24
4.1 Introduction
In developing the monitoring protocols to evaluate the
objectives and outcomes listed above, information was
collected and analysed from a series of existing projects —
Glenelg Ark assessments of detection rates of various native
species undertaken by ARI, a pilot trial undertaken in East
Gippsland for the Southern Ark project, work undertaken
in the Red Fox Adaptive Management Experiment (Robley
and Wright 2003), and work undertaken by ARI in East
Gippsland on Project Deliverance (1998–2003).
Based on a series of meetings and discussions with
the Predator Project Control Board and regional land
management agencies (DSE, PV, Melbourne Water), the
monitoring program comprised three broad components, as
described in the following sections:
1. Measuring changes in Red Fox populations
2. Measuring differences in Red Fox diet pre and post
baiting
3. Measuring changes in native species occurrence
Effective monitoring needs to occur over a longer time
frame than the fire recovery funding permitted and to
commence immediately after a fire event. Given the short
timeframe (effectively 12 months) for activities before
the project reporting timeframe expired and the lag-
time between the fire event and the commencement of
monitoring (19–20 months), the monitoring and evaluation
program for measuring changes in native species was
further broken down to assess:
• Theoccurrenceanddistributionoffaunapreyspeciesin
the fire-affected areas
• TheimmediateimpactofthereductioninRedFox
abundance on native species
• Collectionofbaselinedataforfuturemonitoring
activities.
4.2 Monitoring methods
4.2.2 Measuring changes in Red Fox populations
Monitoring the reduction in Red Foxes resulting from a
Red Fox management program is best achieved through
the comparison of population estimates, either indices
of abundance or some direct measure of abundance
(Saunders et al. 1995). Estimates of abundance derived
from genotyping individual Red Foxes from DNA recovered
from scats were undertaken before and after the control
program.
Scats were collected from 55 kilometres of tracks in the
Kilmore-Murrindindi fire area (Figure 10) and roads within
the study area one week prior to, and one week following,
the initial eight week baiting program. Pre-baiting scat
collection was undertaken by two teams each of two
people. A team walked down a track scanning from the
middle to the outer edge of the track for scats. All predator
scats were collected regardless of their condition and the
location of each scat was recorded using hand held GPS. A
photograph of each scat was also taken in situ and a visual
assessment made of the fire severity history of the location.
Scats were assigned to a burn category from one to four
(Table 5). This table is a simplified version of Table 2 (p14)
used in the SDM modelling procedure.
4 Monitoring the effectiveness of the program
Table 5. Four burn categories of fire intensity used to assess distribution of native species across the study area.
Fire
Severity
Class
Severity Type Description
1 100% Burnt 100% of vegetation is burnt
An intense wildfire with complete vegetation burn
2 Severe scorch 60–100% of vegetation scorched, some vegetation burnt
An intense understorey fire with widespread vegetation scorch
3 Moderate scorch 30–60% of vegetation is scorched
A variable intensity of fire ranging from a light ground burn with minimal scorch to an
intense understorey fire with widespread vegetation scorch
4 Light scorch 0–30% vegetation scorch
A light ground burn with isolated patches of intense understorey fire and unburnt areas
25
Post-baiting scat collection was undertaken by two teams of
scat detection dogs from the Tasmanian Red Fox Eradication
Task Force. A dog and handler walked a section of track and
all Red Fox positive scats encountered were collected, their
location recorded and a photograph taken. A single dog
would be worked for 30 min and then the second dog in
that team would commence searching (Figure 18). Post-
baiting scat searches were undertaken over the same tracks
and roads as the pre-baiting searches.
As in live-trapping methods, population abundances can
be determined by non-invasive sampling such as faecal
genotyping using capture-recapture methods or by directly
counting the number of individuals, the difference being
that unique genotypes rather than live-marked animals are
recorded (Lettink and Armstrong 2003; Lukacs and Burnham
2005; Prugh et al. 2005). Capture-recapture using DNA
obtained from Red Fox scats has been undertaken in East
Gippsland (Diment 2010) and from trapped hair for estimating
Grizzly Bear (Ursus arctos) and Black Bear (Ursus americanus)
abundance in British Columbia and Alberta (Woods et al.
1999; Romain-Bondi et al. 2004; Wasser et al. 2004).
Mark–recapture models can be applied to closed or open
populations (Lettink and Armstrong 2003). Most faecal
genotyping studies have used closed-population models
using the Lincoln-Petersen estimator, which assumes a
constant population during the sampling period (e.g.
Kohn et al. 1999; Harrison et al. 2002; Frantz et al. 2003;
Wasser et al. 2004). Although more difficult because
population parameters such as births, deaths, immigration
or emigration must be taken into account (Lettink and
Armstrong 2003), faecal mark–recapture sampling for open
populations has also been carried out. Prugh et al. (2005)
evaluated this approach by sampling a wolf population
in Alaska over a three-year period and concluded that
faecal genotyping is an effective approach for monitoring
populations over a longer time scale. For full details see
MacDonald and Sarre (2011).
4.2.3 Capture rates for Red Foxes pre and post
predator control
Pre and post fox control heat-in-motion digital cameras
(ScoutGuard, SG550V; HCO, Norcross, Georgia, USA) were
set for 21 days to assess changes in camera capture rates of
Red Foxes. The number of independent images of Red Foxes
per 24 hours recorded for each of the four burn categories
(Table 5) was used to assess changes in Red Fox activity in
relation to fire intensity. The hypothesis that observations
were equally distributed across the four burn categories in
the pre- and post-control survey period was tested using
a chi-square test for goodness-of-fit. Where observations
were below five per cell, we either grouped observations
or removed them from the analysis. In all tests we applied
Yates’ correction (Zar 1999).
Figure 18. Tasmanian Red Fox scat collecting team. Handler Olivia Barnard with Tommy and Buddy, and Handler David
Cunningham with Bluey and Orange.
26
4.2.4 Measuring Red Fox diet pre and post baiting
A random selection of eighty scats that were collected for
assessment of changes in abundance of Red Foxes was
sent for diet analysis by B. Triggs. The proportion of each
individual prey item from each scat was recorded and
assigned to a burn category.
4.3 Measuring changes in native species
populations
4.3.1 Camera capture rate
A pre-baiting and post-baiting survey of native ground-
dwelling animal species was undertaken using remotely
activated digital cameras set at 40 locations each over a
37 day period. Two camera types were used. Pixcontroller
cameras (Pixcontroller Inc., Export, Pennsylvania, USA) which
take white flash colour images and ScoutGuard (SG550V;
HCO, Norcross, Georgia, USA) which take colour daytime and
infrared night-time images. Night-time infrared images reduce
the ability to identify small mammals. We differentiated small
and intermediate-sized mammals based on relative body
size and, where possible, head shape and tail length (e.g.
Antechinus <100 mm body length and Bush Rat between
100 mm and 200 mm body length). The feeder stations
at each location provided a known scale against which we
could determine relative body size (Figure 19). Both cameras
recorded the date and time when images were collected.
At sites with ScoutGuard cameras, a feeding station was filled
with a mixture of dog kibble (Artimis Pty Ltd, Melbourne) and
pistachio essence, and placed 1.5 m in front of a camera.
This feeder station was used in an attempt to maximise the
time small and intermediate-sized mammals spent at a site to
aid in identification. Sites with PixController cameras had a
lure of pistachio essence and flax oil soaked in oil absorbent
cloth (Matt Spill GP-Grade, All Trade Industrial Supplies,
Melbourne) suspended in a tea-infuser inside a small wire
cage, attached to a 1.5 m stake, 2 m from a camera (front
cover image). Species were identified from the images
obtained and captures per 100 camera trap nights used to
assess differences before and after control.
4.3.2 Changes in site occupancy of native species
In addition to camera capture rate, we used site occupancy
(the proportion of a monitoring area that is occupied) to
assess changes in species at risk from Red Fox predation
over the short-term. The term ‘occupancy’ is used here to
mean the proportion of sampling units (the areas treated for
Red Fox control) that contain the target species at a given
point in time.
To estimate the probability a site is occupied by a species
of interest, we used the modelling approach developed
by MacKenzie et al. (2002). Typically, species are not
guaranteed to be detected even when present at a site,
hence the naïve estimate of occupancy is given by:
# sites where species detected
Naïve occupancy = total # sites surveyed
This will underestimate the true rate of occupancy. MacKenzie
et al. (2002) propose that by repeated surveying the sites, the
probability of detecting the species can be estimated, which
then enables unbiased estimation of occupancy.
We undertook analysis using the software program PRESENCE
(version 3.1 Hines 2006). PRESENCE uses maximum likelihood
to simultaneously estimate detection probabilities (p) and
occupancy (psi) from detection history data and evaluates
factors that may influence detection (or occupancy) at a given
site. Using the single-season occupancy model (MacKenzie et
al. 2006), we used the a priori model psi(.), p(.) to determine
occupancy rates. The difference in occupancy rate between
pre and post-control for each species was calculated. If Red
Fox control has a statistically significant, positive effect then
the entire 95% credible interval (CI) will be above zero. If
the treatment has a statistically significant, negative effect
then the entire 95% CI will be below zero. Where the 95%
CI includes zero, no conclusion can be made regarding the
statistical significance of treatment.
Figure 19. Example of a small and intermediate-sized mammal captured by remote camera.
a) small mammal, <100 mm body length, and b) a intermediate-sized mammal, between 100 mm and 200 mm head–body
length, most likely an Antechinus Antechinus sp. and a Bush Rat Rattus fuscipes respectively.
a) b)
27
4.4 Monitoring results
4.4.1 Changes in Red Fox abundance
DNA identification and microsatellite profiling of Red
Fox scats pre and post-Red Fox control
Prior to Red Fox baiting, 87 predator scats were collected
from 55 kilometres of track by two teams of two people
between 27 and 30 September 2010 (Figure 20). Scats
were collected regardless of their condition, which varied
considerably from very fresh to weathered and degraded
(Figure 21). Post-baiting, we collected 172 scats using the
dog teams between 30 November and 4 December 2010
from the same tracks as in the pre-baiting surveys. Eighty
scats were considered to be in a condition suitable to
attempt DNA extraction (e.g. scats a, b and c but not d in
Figure 21).
Figure 20. Location of scat collection transects during the pre- and post-Red Fox control surveys in September and November/
December 2010.
Land Tenure
Parks and Reserves Lake Eildon Road/Tracks
State Forest Scat Transects
N 0 2 4 kilometres
28
Figure 21. Predator scats collected showing vary degrees of decomposition
a) fresh, b) dried, c) washed out, and d) degraded.
a) b)
c) d)
Of the 80 scats collected and sent for DNA testing, only 79 had sufficient DNA material for assessment: 43 scats from the
pre-control sample and 36 scats from the post-control sample. Of those, 24 scats from the pre-control sample and 31 scats
from the post-control sample had sufficient quality and quantity material to successfully identify Red Fox DNA (Figure 22).
Mammalian DNA, but not Red Fox DNA, was detected from a further 24 of the 79 scats, suggesting that these originate
from other mammalian carnivores (i.e. wild dogs or feral cats).
29
Figure 22. Location of Red Fox positive scats pre and post control.
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Land Tenure
Parks and Reserves Lake Eildon Road/Tracks Pre-control
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Individual DNA profiling was attempted for all 55 scats
found to be positive for Red Fox DNA, using 11 microsatellite
loci and a sex (Y-specific) marker. Six replicate genotyping
reactions were set up for each scat.
Twenty-two scats were found to contain male DNA, ten scats
were scored as female and sex could not be determined in the
remaining scats. Ten microsatellite loci were polymorphic in
the samples tested, although the number of alleles observed
(2–7 alleles per polymorphic locus) was relatively low.
Microsatellite genotyping success was mixed, with good
amplification from some scats but poor or no amplification
from others. Genotypes were scored using two sets of
criteria: ‘strict’ criteria designed to minimise the effect of
genotyping errors and ‘relaxed’ criteria designed to maximise
the available data given the variable genotyping success
observed. Population genetic and identity analyses were
conducted using both of these datasets.
Analyses of genetic differentiation between the pre and post
control samples indicate that all scats analysed should be
treated as originating from a single genetic population.
Five sets of scats with matching or near-matching genotypes,
which may originate from the same or closely related Red
Foxes, were identified. Identity analyses indicate that in at
least two cases, pairs of scats collected in the pre- and post-
control samples originated from the same individual Red Fox.
That is to say, at least two Red Foxes present before baiting,
were still present post-baiting.
Low quantity and quality of DNA in many of the scats
resulted in the low sample size of individually identified Red
Foxes. This prevented mark–recapture analysis or analysis
to investigate the density of Red Foxes pre and post control
being conducted.
30
Of the five individual Red Foxes identified (four male and
one female), four were located in the pre control survey,
and of these two were re-discovered during the post baiting
phase. One of the five Red Foxes was only found in the post
control phase.
Use of Burn Categories
Low sample size prevented statistical analysis in the pre-
control survey. There were zero captures in the 100% Burnt
and Severe Scorch categories and observations of Red Foxes
in the Moderate and Light Scorch categories did not differ
from that expected based on the proportion of camera trap
nights. The fact that no observations were made in the
100% Burnt and Severe Scorch categories suggests that
use in these categories was lower than in the Moderate and
Light Scorch categories.
In the post-control survey there were sufficient observations
to test across all four burn categories. We observed more
Red Fox captures in the Severe Scorch and less in the
Moderate Scorch than would be expected based on the
proportion of camera trap nights
(X2 =12.3481, df=3, p = 0.006).
4.4.2 Food items in Red Fox scats
The dietary composition of 80 scats from the pre and post-
baiting surveys was analysed. The proportion of prey items
in each scat was identified (Figure 23). The most common
item was mammalian, comprising Trichosurus sp., (42%)
most likely Mountain Brushtail Possum (T. cunninghami),
followed by Swamp Wallaby (Wallabia bicolor; 14%) and
Rabbit (Oryctolagus cuniculus; 11%). There was a trend
towards an increase in insects and a decrease in birds in the
post-control period.
Within the mammalian food items, there was a shift
in the composition. In the pre-baiting period, Red Fox
diet comprised 12 species including House Mouse (Mus
musculus), Eastern Grey Kangaroo (Macropus giganteus),
Feathertail Glider (Acrobates pygmaeus), Eastern Pygmy-
possum (Cercartetus nanus), Dusky Antechinus (Antechinus
swainsonii) and Swamp Rat (Rattus lutreolus), which did not
appear in the post-control diet. In the post-baiting period,
Red Fox diet comprised nine species. The major food items
in the post-control samples were Trichosurus spp., European
Rabbit (Oryctolagus cuniculus) and Swamp Wallaby
(Wallabia bicolor).
The percentage of food items found in scats (pre and post-
control combined) in proportion to the number of scats
collected in each burn class is shown in Figure 24. Mammals
were slightly more common in the Moderate Scorch class
whilst birds were slightly more common in the Light Scorch
class. Insects decreased as a food item as fire intensity
decreased, while plant material was greatest in the least
intensely burnt areas.
Changes in pre and post control habitat use in relation
to fire intensity
Results of the chi-square test indicated that the frequency
of Red Fox scats collected across the fire altered landscape
pre-control were made in proportion to the sampling effort
within each of the fire intensity categories (X2 = 9.0684,
df = 3, p = 0.03). That is, there was no difference in the
presence of Red Foxes across the fire landscape. Post-
control, Red Foxes used the landscape differently across the
four fire severity classes (X2 = 12.35, df = 3, p = 0.006). Red
Foxes were observed more in Severely Burnt patches and
less in Moderately Burnt patches than expected.
100
90
80
70
60
50
40
30
20
10
0
Plant
Insects
Birds
Mammals
Pre-control Post-control
Percentage of items in scats
Plants Insects Birds Mammals
100
80
60
40
20
0
100% Severe Moderate Light
burnt scorch scorch scorch
Percentage of items in scats
Figure 23. Percentage of food items in Red Fox scats pre- and
post-control.
Figure 24. Percentage of food items in Red Fox scats across
fire categories.
31
4.4.3 Native species response
Presence and distribution of native species
The influence of burn category and fox control on the
abundance and occupancy rate of species captured on
remotely activated digital cameras, using captures/100
trap nights and occupancy estimation respectively, was
investigated. For the assessment of the influence of burn
category on the distribution of species the pre-Red Fox
control camera survey data only was used. This was to
provide baseline data for later comparisons of change
through time associated with a) fox control and b) post-fire
habitat change as part of any future long-term monitoring
program. In the assessment of occupancy related to fox
control, both the combined Pixcontroller/ScoutGuard pre-
control data and the ScoutGuard only post-control data
was used.
Pre Red Fox control, 39 Pixcontroller and 39 ScoutGuard
cameras were set between 31 August 2010 and 8 October
2010 for an average of 26 days ± 2 days. Of these, five
ScoutGuard and eight Pixcontroller cameras completely
failed. Post Red Fox control, 39 ScoutGuard cameras
were deployed to the same locations as the pre-control
period between 15 November and 15 December 2010
for an average of 24 days ± 5 days. Of these, 10 cameras
completely failed before the sample period was complete.
Figure 25 indicates the general location of cameras in this
study. In the pre Red Fox control survey, ScoutGuard and
Pixcontroller cameras were placed on opposite sides of a
track and separated by a minimum of 500 metres. In the post
Red Fox control survey, ScoutGuard cameras were placed in
the same location as in the pre Red Fox control survey.
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N 0 2 4 kilometres
Figure 25. Location of ScoutGuard digital cameras used in the pre and post-baiting survey.
32
We recorded 190 camera-captures of 13 species across the
four fire categories shown in Table 8. In proportion to the
camera/trap nights in each burn category, the majority of
captures were within the Severe Scorch category, with 11
of the 13 species being captured most frequently in this
category (Table 9; Figure 26).
Only four species were recorded in all four burn categories,
and only the Red Fox was recorded in near equal proportion
across all four categories (albeit at a low rate). This suggests
that Red Foxes were at least widespread, if not common
across the site. Camera capture rates for Swamp Wallabies
were highest in the Severe and Moderate categories,
Mountain Brushtail Possums and Superb Lyrebirds were
more frequently captured in Severe Scorch and Light Scorch
areas. Small mammals, including Antechinus spp. and
Smoky Mouse were most often captured on cameras in
the Severe Scorch category. Echidnas were captured more
often in Severely Burnt and Moderate Scorch than any other
category, while European Rabbits were found in only two
burn categories, and more often in Moderate Scorch areas.
Table 6. Captures per 100 camera trap nights in four burn categories from the pre-Red Fox control ScoutGuard and
Pixcontroller camera survey. Captures are the number of individuals per site within a burn category/total number of camera
nights within a burn category. For example, in 100 trap nights we expect to capture 1.3 Swamp Wallaby in 100% Burnt areas.
Species Common Name 100% Burnt Severe Scorch Moderate
Scorch
Light Scorch Total captures/
100 camera
trap nights
Swamp Wallaby 1.30 2.65 2.53 1.66 2.08
Mountain Brushtail Possum 0.43 2.27 1.04 1.91 1.51
Superb Lyrebird 0.43 1.89 0.74 1.66 1.25
Common Wombat 0.00 1.14 1.19 1.15 1.04
Indeterminate mammal * 0.00 1.52 0.74 0.64 0.73
Feral Cat 0.00 0.76 0.74 0.51 0.57
Bush Rat 0.00 0.76 0.60 0.51 0.52
Echidna 0.00 0.76 0.74 0.38 0.52
Antechinus spp. 0.43 1.14 0.15 0.51 0.47
Red Fox 0.43 0.38 0.30 0.51 0.42
Small mammal * 0.00 1.14 0.45 0.26 0.42
European Rabbit 0.00 0.00 0.45 0.13 0.21
Smoky Mouse 0.00 0.76 0.15 0.00 0.16
*Small mammal, <100 mm body length, and intermediate-sized mammal, between 100 mm and 200 mm head–body length.
33
Figure 26. Species captures per 100 camera trap nights in four burn categories from the pre Red Fox control ScoutGuard and
Pixcontroller combined camera survey.
100% Burnt
Severe Scorch
Moderate Scorch
Light Scorch
3.00
2.50
2.00
1.50
1.00
0.05
0
Smoky Mouse
Swamp Wallaby
Moutain Bushtail Possum
Superb Lyerbird
Common Wombat
Internation mammal
Feral Cat
Bush Rat
Echidna
Antechinus spp.
Red Fox
Small mammal
European Rabbit
Site occupancy estimates of native species
As part of the potential long-term monitoring program,
occupancy rates for all species that had sufficient data,
including introduced predators, were estimated (Table 7).
We also assessed the difference in pre- and post-control
occupancy estimates to determine the impact of Red Fox
control (Figure 27).
Occupancy estimates were determined for all species
detected by cameras (combined Pixcontroller/ScoutGuard
surveys pre-control and ScoutGuard surveys post-control),
with the exception of Echidna, for which there were too
few encounters. Pre-control estimates were highest for
Common Wombat, Feral Cat and Swamp Wallaby, and
lowest for Red Foxes. In the post-control survey, occupancy
was highest for Swamp Wallaby and Superb Lyrebird and
lowest for small mammals.
Table 7. Occupancy estimates for species detected during
pre- and post-Red Fox control survey.
Species Occupancy
Pre-Control
(SE)
Post-Control
(SE)
Mountain Brushtail Possum 0.352 (0.095) 0.330 (0.092)
Feral Cat 0.524 (0.312) 0.085 (0.062)
Red Fox 0.111 (0.060) 0.173 (0.070)
Intermediate mammals 0.283 (0.080) 0.277 (0.083)
Superb Lyrebird 0.268 (0.094) 0.541 (0.121)
Small mammals 0.253 (0.086) 0.034 (0.034)
Swamp Wallaby 0.497 (0.131) 0.584 (0.123)
Common Wombat 0.552 (0.188) NA
NB: small mammal, <100 mm body length, and intermediate-sized
mammal, between 100 mm and 200 mm head–body length.
34
There was no change in occupancy for Red Foxes. There
was an increase in occupancy rate for Superb Lyrebird, and
a substantial decrease in estimates for Feral Cat and small
mammals. Estimates for the remaining species remained
effectively unchanged.
The probability that there was a significant treatment effect
is shown in Table 8. There was no detectable positive effect
of control on Red Foxes. There was a significant positive
effect of treatment on Superb Lyrebird, and a significant
negative effect on small mammals. There was a substantial,
but not statistically significant, decrease in Feral Cat post-
control.
4.5 Monitoring discussion
Red Foxes were monitored pre and post the initial eight-
week 1080 poison baiting program. The overall baiting
program covered a wider area than that where the
monitoring program was implemented. As such, Parks
Victoria had several contractors implementing the baiting
program. An unforeseen result of this was that more than
one contractor was operating over the monitoring area.
Despite Parks Victoria’s efforts to standardise the way in
which contractors collected and reported the results of the
baiting operation, inconsistencies made collation of the data
problematic.
Figure 27. Effect size of Red Fox control on occupancy estimates pre and post Red Fox control. Bars are upper and lower
confidence limits.
Table 8. Probability of a significant difference between pre- and post-control occupancy estimates. For example there is a 97%
probability that the confidence intervals for Superb Lyrebird do not overlap with zero, i.e., p = 0.03.
Mountain
Brushtail
Possum
Feral Cat Red Fox Intermediate
mammals
Superb
Lyrebird
Small
mammals
Swamp
Wallaby
Probability 0.41 0.08 0.76 0.49 0.97 0.01 0.70
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.2
Mountain
Brushtail
Possum
Feral
Cat
Red
Fox
*Intermediate
mammals
Superb
Lyrebird
*Small
mammals
Swamp
Wallaby
Relative effect of fox control
35
Non-invasive genetic approaches were successfully applied
to identify 55 scats that were positive for Red Fox DNA
and to identify the sex of the animal of 32 of these scats.
Microsatellite genotyping success was varied, but was
able to obtain usable individual profiles for up to 20 scat
samples, using strict or relaxed scoring criteria. Population
genetic analyses indicate that overall genetic diversity was
fairly low and that the pre and post-control samples should
be treated as originating from a single genetic population
(i.e. that there is no significant genetic differentiation
between samples collected before Red Fox control measures
were conducted and those collected afterwards). This may
indicate that the control measures did not significantly
reduce the Red Fox population present in the area studied,
but it is also possible that this area is part of a larger
genetic population and that new migrants post-control
cannot be distinguished from individuals present in the area
pre-control. Further population genetic studies would be
needed to determine this. Identity analyses indicate that
some of the genotypes observed were sampled multiple
times, suggesting that in some cases two or more of the
scats analysed were left by the same individual Red Fox.
In two instances, scats with matching genotypes were
collected pre and post-control, suggesting that at least two
individual Red Foxes were present in the study area both
before and after the control measures were conducted.
However, in a population of closely related animals with low
genetic diversity it is likely that different individuals will have
similar genotypes, so more information on the size and the
genetic structure of the Red Fox population of the wider
area, which is a potential source of migrants to the study
area, would be useful to determine the likelihood of these
different possibilities.
Due to the low sample size of individually identified Red
Foxes resulting from low quality and quantity of DNA
material in the samples collected, mark–recapture analysis or
analysis to investigate the density of Red Fox’s pre- and post-
control was unable to be conducted. Thus, it is not possible
to draw any robust conclusions about the effectiveness of
the Red Fox control program.
However, the area covered by the scat sampling (54 km2)
would be capable of holding between 10 and 97 Red Foxes
based on density estimates of 0.2 / km2 in dry sclerophyll
forest in coastal NSW (Newsome and Catling 1992) and
1.8 / km2 in sub-alpine eastern NSW (Saunders et al. 1995).
Our surveys were undertaken 18 months post-fire and the
impact on survival and recolonisation is unknown for Red
Foxes. It may be that prey densities have recovered but
the Red Fox population is lagging behind. Identification of
individual Red Foxes from scats was hampered by a lack of
quality DNA material extracted from scats. It is likely that
there are more than five individuals in the study area.
In future control operations broader sampling of the wider
pre-control population would be advisable, as would the
use of scat detector dogs to firstly clear an area of scats
prior to the pre and post-control sampling. It is likely that
scats missed by the human survey teams in the pre-control
survey were discovered by the dog survey teams in the post-
control period. Given the short timeframe for implementing
the baiting and monitoring programs it was not possible to
engage the dog teams in the initial survey or to sweep the
areas clan prior to the collection surveys.
Camera trapping rates indicated that Red Foxes increased
following the initial eight-week baiting program. In the
post-control survey, juvenile Red Foxes were recorded at
a number of sites, while in the pre-control period none
where recorded. Births of Red Foxes peak in August/
September in temperate parts of Australia, with dispersal of
independent animals occurring through summer (Saunders
et al. 1995). This would be around the time of the second
survey (December). It is possible that the control program
removed a number of adult Red Foxes and that the void
was filled by dispersing young from within and surrounding
areas. Saunders et al. (2007) note that Red Foxes are able to
quickly reinvade areas that have been baited. The increase
in camera trapping rates could be a measure of the rapid
rate of reinvasion from surrounding ‘floater’ Red Foxes.
A third possibility is that the baiting program removed
some individual ‘mates’ and the remaining Red Foxes were
exploring a wider area either in search of missing individuals
or exploring ‘vacant’ territory (Saunders et al. 2007). This
highlights the importance of follow up control within a
short period of time, the need for constant control activities
and the need for follow up and long-term monitoring. It is
also possible that few if any foxes were killed by the control
program.
The monitoring and evaluation program was implemented
18 months post-fire. It is not known how habitat structure
has changed in the time since the fire passed through the
landscape. Four fire intensity classes based on immediate
post-fire remote sensing undertaken by DSE were identified.
Red Foxes showed no sign of selecting for habitat based on
these classes during the pre-control survey period, but did
show some preference for Severely Scorched and a lesser
preference for Moderately Scorched habitat than expected
during the post control period. However, it is possible that
in the intervening time the habitat has recovered to such a
degree that the resources required by Red Foxes are now
present across these classes and that selection of habitat is
being driven by other factors not measured here.
Red Fox scats collected in this study comprised mainly
mammalian food items of which Mountain Brushtail
Possum, Swamp Wallaby and European Rabbit were the
most common. Insects and plants were also common
elements. This is consistent with previous studies that have
shown that Red Foxes are carnivorous, mainly consuming
mammals, but that insects and plant material make up a
considerable proportion of their diet (Saunders et al. 1995).
36
Importantly, the proportional composition of dietary items
may not be an indicator of the impact Red Foxes are having
on native species. Species that were rare in Red Fox scats
were Feathertail Glider (Acrobates pygmaeus), Sugar Glider
(Petaurus breviceps), Greater Glider (Petauroides volans),
Common Ringtail Possum (Pseudocheirus peregrinus)
and Eastern Pygmy-possum (Cercartetus nanus; Near
Threatened). None of these species were detected by remote
digital cameras as all are primarily arboreal. The scat survey
has confirmed the presence of these species in areas that
were subject to the 2009 fires. It also provides an indication
that post-fire predation in fire impacted habitats may
have an important impact of the resilience of ecosystems
subjected to fire.
There appeared to be some influence on the distribution
of native species in relation to fire intensity. Only five of the
13 recorded species were found in the 100% Burnt habitat,
while the majority of captures were within the Severe
Scorch category, with 11 of the 13 species being captured
most frequently in this category. The most common species
in relation to all fire categories were Swamp Wallaby,
Mountain Brushtail Possum and Superb Lyrebird. The least
widespread species were Smoky Mouse and European
Rabbit. Red Foxes were found in nearly equal proportion in
all four burn categories suggesting they were widespread,
if in low density.
The use of occupancy estimates based on detection of
target species at monitoring sites as used in this study
is a widely acceptable method for assessing success of
biodiversity conservation actions (Mackenzie et al. 2006).
We have established baseline data that could be used in
long-term monitoring. This would require establishing
monitoring protocols to detect species at the 40 monitoring
stations established throughout the study area. We used
digital cameras; however, hair tubes could be used if
cameras were not available. While the cost of operating hair
tubes and cameras is comparable, the range of species that
can be detected by cameras is greater making the use of
digital cameras preferable.
The timing of the monitoring sessions for detecting changes
in native species occupancy is related to two factors: a)
limited understanding of the population dynamics of the
target native species, and b) the likely impact of Red Fox
predation on those dynamics. If juveniles of native species
are more susceptible to predation than adults, recruitment
into the population will be low. If this cohort has been
preferentially targeted by Red Fox predation then, in theory,
there will be more individuals available in the landscape
for detection through the years on treated sites and as
the population increases so will the sites they occupy.
Alternatively, if adults are more vulnerable then
reproductive output would be reduced.
One monitoring session was undertaken prior to the initial
eight-week baiting phase. While less than ideal, this is all
that could be achieved given the implementation timeframe.
This data will provide critical information on the starting
condition of the monitoring area and lays the foundation for
longer-term monitoring. However, it needs to be recognised
that this design has significant limitations on the ability to
interpret any associations with changes in fox numbers
through time.
Unless monitoring and evaluation are recurrent components
of management, management will have no capacity to a)
justify reinvestment of scarce public conservation funds, b)
improve management actions based on reliable information
about the effectiveness of previous management actions,
and c) maintain community support. Thus, monitoring and
evaluation should be seen as a part of management not an
imposition or adjunct to it.
37
5 Recommendations
Preparedness recommendations
This project has contributed to the knowledge and processes
that underpin an enhanced response to future fire events.
Strategic planning could be enhanced by developing the
data sets and information tools necessary to prepare for
future emergency events in which predation may be a
significant risk. Forward preparation of mapped locations
for priority control of pest animals, with or without a major
disturbance, would benefit rapid response to emergencies.
It would also enable priority areas for predator control to be
targeted prior to the potential negative effects of fire.
Pre fire data on predators and prey populations, and a
capacity to rapidly acquire data on predator and prey
populations immediately following fire would be beneficial,
including the option of using trained dogs for scat collection.
As predation is likely to have its most significant effect
immediately following a fire event, early access to funding,
even in relatively small amounts, would enhance the
capacity for rapid response and more effective outcomes.
Preparation of standard monitoring and recording systems
(e.g. for bait take data) and tools, such as smartphone
applications, would ensure appropriate and comparative
data was being recorded across a wide range of users
involved in implementation of predator control programs.
Project recommendations
The following recommendations are made to guide future
projects:
Planning – Issues associated with such factors as inclement
weather, difficult terrain, poor access and track
conditions, fuel reduction burns, animal behaviour etc.
need to be factored in when planning future fox control
programs. Flexibility should be built into the program to
cater for these variables.
Document preparation and timing – In planning future
programs, required approvals and documentation (such
as the PV/DSE Application to Control Pest Animals
documents) should be obtained well beforehand to avoid
delaying commencement of a program.
Risk Identification and Management – Due to the
remote and rough nature of the program area,
contractor and supervisor safety needed careful
consideration. Potential risks can be mitigated through
the use of well maintained vehicles equipped with UHF
and trunk radios, high gain mobile phone antennas,
recovery equipment, first aid, personal locator beacons,
personal protective equipment, etcetera and by way of
communication protocols such as checking in and out
of areas by text message and leaving daily route/location
details with relevant supervisors and at work centres.
These equipment and procedural requirements should
be incorporated into job safety documents.
Communications – As Shire mailout lists will not reach all
properties, future projects should anticipate the need
for additional, hand-delivered, landowner notifications.
Additional signage and media would be useful to alert
the public to the program and its value. Increased
interaction and engagement with user groups and
the community prior to a baiting run to ascertain their
recreational habits and possibly modify the baiting areas
would be beneficial.
Use of bait station cameras – More extensive use of
remote cameras at selected bait stations would provide
more comprehensive monitoring data, particularly where
there is a risk of off-target bait take to identify species
potentially affected.
Ongoing fox control – A fox baiting program should
be undertaken over an adequate length of time to
maximise effectiveness and efficiency of the program.
The timeframe could be based on the degree of
redevelopment of habitat, which may take 3–5 years
depending on vegetation type and site variables.
Suppression of the Red Fox population – Bait take data
should be analysed for each round of baiting. Mitchell
and Balogh (2009) describe methods for converting bait
take data into an index of abundance using frequency/
density transformation.
Digital cameras (maximum two per km2 set for a minimum
of 21 days using a predator lure) can also be used to assess
trends in occupancy. This approach could also be used to
assess trends in occupancy rates of Feral Cat. It would not
be appropriate to use digital cameras for assessing changes
in native species at the same sites as for introduced
predators, as this combination would require luring
introduced predators and native species to the same site.
Monitoring changes in predator diet – Continued
annual assessment of the proportional composition of
Red Fox diet would provide information on the spatial
and temporal change in distribution of a range of native
species that were not detected by camera survey. Scat
collection should occur at the same time and place as in
this study.
Monitoring changes in native species – Further
interrogation of the model output to identify those
species that comprised the overall biodiversity benefit
described in the model. This information could be used
to better target monitoring methods to those species.
Site occupancy may change over years as populations
change. When sites are surveyed between these periods
of change, over a number of years, the approach
described here can be combined with a robust mark–
recapture approach (Pollock et al. 1990). Sampling, using
digital cameras should be repeated at the same site
each year and continued for several years. The change
in occupancy rates over years could then be modelled
38
as a function of site colonisation and extinction rates,
analogous with birth and death rates in an open-
population mark–recapture study, and explanatory
variables such has fire history, presence of predators and
changes in vegetation structure can be incorporated into
the analysis.
While the monitoring and evaluation of selected indicator
species has been designed using the best available data,
it is strongly recommended that in future, after the first
year, the data collected is used to reassess the sampling
design and, if necessary, amend the monitoring program.
39
6 Beyond this project – a postscript
Native species response
Small mammal surveys at Bellell Creek in the Kilmore
East-Murrindindi fire area recorded the return of Agile
Antechinus Antechinus agilis and Dusky Antechinus
Antechinus swainsonii to the site, albeit in low numbers.
These most recent results are encouraging and indicate that
the small mammal population at Bellell Creek is only just
beginning to recover after the disturbance caused by the
Black Saturday bushfires. Surveillance cameras have resulted
in the near threatened Eastern Pygmy-possum Cecartetus
nanus being detected within close proximity to the site. The
cameras also detected feral predators in the area and were a
valuable survey tool for the program (Biosis Research 2011).
These survey results reinforce the importance of continuous
and regular predator control.
During 2012 to 2013 there have been numerous sightings
and a number of reports of road killed Long-nosed
Bandicoots Perameles nasuta across much of the area
impacted by the 2009 Kilmore-Murrindindi fire. Bandicoots
are one of the ‘at risk’ native species preyed on by Red
Foxes. The apparent recovery of this species coincides with
good rainfall in 2011–12 and thick fire regrowth which
provides cover. Although difficult to measure, this predator
control project and the continuing Central Highlands Ark
Project (see below) are likely to have contributed.
Central Highlands Ark Project and long-term
monitoring
DSE and partner agencies are continuing Red Fox control
in the Kilmore-Murrindindi fire area as part of the new
CHAP which commenced in 2012 and covers 150,000
hectares. The project is focused on Red Fox control using
1080 baiting. Sustained, regular pulse treatments are being
used. The project is currently funded until 2014. The project
includes a monitoring component aimed at measuring
changes in both Red Fox abundance and the abundance
of native species at risk of Red Fox predation.
40
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42
Appendix 1 Relative ranking of fauna species
considered to be at risk from Red Fox predation
Relative weightings (RW) are the cubed product of weightings previously developed by Robley and Choquenot (2002).
Species not included in the site prioritisation analysis are indicated by an asterisk.
Species RW
Eastern Barred Bandicoot 1.00
Long-footed Potoroo 1.00
Bush Stone Curlew 0.97
Brush-tailed Rock Wallaby 0.94
Long-nosed Potoroo 0.91
Heath Mouse * 0.91
Heath Skink 0.83
Millewa Skink * 0.83
Little Tern 0.78
Hooded Plover 0.78
Common Dunnart 0.78
Long-nosed Bandicoot 0.75
Silky Mouse 0.70
Mallee Ningaui 0.64
Fat-tailed Dunnart 0.64
Southern Brown Bandicoot 0.64
Bardick 0.64
Port Lincoln Snake * 0.64
Plains-wanderer 0.59
Malleefowl 0.57
White-footed Dunnart 0.57
Yellow-footed Antechinus 0.55
Mueller’s Skink * 0.55
Magpie Goose 0.53
Brush-tailed Phascogale 0.53
Hooded Scaly-foot 0.53
Samphire Skink 0.53
Alpine She-oak Skink 0.53
Australian Bustard 0.49
Common Wombat 0.49
Water Rat 0.49
Species RW
Broad-toothed Rat 0.49
New Holland Mouse 0.49
Smoky Mouse (Eastern and Western forms) 0.49
Curl Snake 0.49
Brolga 0.46
Redthroat 0.46
Spot-tailed Quoll 0.46
Paucident Planigale 0.46
Mountain Pygmy-possum 0.46
Diamond Dove 0.44
Glossy Ibis * 0.44
Mitchell’s Hopping-mouse 0.44
Red-chested Button-quail 0.41
Red-lored Whistler 0.41
Striated Grasswren 0.41
Short-beaked Echidna 0.41
Common Brushtail Possum 0.41
Beaked Gecko 0.41
Pink-tailed Worm-lizard 0.41
Red-naped Snake 0.41
Corangamite Water Skink 0.41
Eastern Wallaroo * 0.37
Short-tailed Shearwater 0.36
Gull-billed Tern 0.36
Caspian Tern 0.36
Great Egret 0.36
Barking Owl 0.36
Slender-billed Thornbill 0.36
Swamp Antechinus 0.36
Striped Legless Lizard 0.36
Alpine Bog Skink 0.36
Continued next page
43
Species RW
Cape Barren Goose 0.34
Rosenberg’s Goanna 0.34
Crested Tern 0.33
Bush Rat 0.33
Australasian Gannet 0.31
Eastern Curlew * 0.31
Ground Parrot 0.31
Rainbow Bee-eater 0.31
Speckled Warbler 0.31
Cattle Egret 0.31
Dusky Antechinus 0.31
Squirrel Glider 0.31
Baillon’s Crake 0.29
Fairy Tern 0.29
Turquoise Parrot 0.29
Orange-bellied Parrot 0.29
Eastern Bristlebird 0.29
Mallee Emu-wren 0.29
Agile Antechinus 0.29
Australasian Bittern 0.27
Mountain Brushtail Possum 0.26
Greater Glider 0.26
Lewin’s Rail 0.25
Red-necked Wallaby 0.25
Swamp Skink 0.25
Alpine Water Skink 0.25
Carpet Python 0.24
Black-faced Cormorant 0.23
Spotted Bowerbird * 0.23
Diamond Python 0.23
Painted Honeyeater 0.22
Species RW
King Quail 0.21
Grey-crowned Babbler 0.21
Common Death Adder * 0.21
Lined Earless Dragon 0.21
Grasslands Earless Dragon 0.21
Barking Marsh Frog 0.21
Giant Bullfrog 0.21
Southern Barred Frog * 0.21
Tyler’s Toadlet * 0.21
Freckled Duck 0.20
Woodland Blind Snake 0.20
Musk Duck 0.18
Rufous Bristlebird * 0.18
Leadbeaters Possum 0.18
Feathertail Glider 0.18
Little Pygmy-possum 0.18
Tessellated Gecko 0.18
Martin’s Toadlet * 0.18
Darter 0.15
Royal Spoonbill 0.15
Intermediate Egret 0.15
Nankeen Night Heron 0.15
Little Bittern 0.15
Square-tailed Kite 0.15
Ground Cuckoo-shrike 0.15
Swamp Rat 0.15
Eastern Water Skink 0.15
Chestnut-rumped Heathwren 0.13
Western Pygmy-possum 0.13
Western Blue-tongued Lizard 0.13
Warty Bell Frog 0.13
Appendix 1 continued
Continued next page
44
Species RW
Pied Cormorant 0.11
Painted Snipe * 0.11
Blue-billed Duck 0.11
Common Ringtail Possum 0.11
Yellow-bellied Glider 0.11
Sugar Glider 0.11
Swamp Wallaby 0.11
Baw Baw Frog 0.11
Booroolong Tree Frog * 0.11
Eastern Pygmy-possum 0.10
Large Brown Tree Frog * 0.10
Apostlebird 0.09
Broad-shelled Tortoise 0.09
Giant Burrowing Frog 0.09
Spotted Tree Frog 0.09
Alpine Tree Frog 0.09
Desert Skink 0.07
Bandy Bandy 0.07
Whiskered Tern 0.06
Rugose Toadlet * 0.06
Bynoe’s Gecko 0.05
Appendix 1 continued
45
Appendix 2 Percentage of food items in 80 scats
collected from the study area
Composition (%)
Survey Common Name Scientific Name Mammal Bird Insect Plant
Post-control Deer Cervus sp. 10 90
Post-control Deer Cervus sp.10 20
Post-control no hairs 100
Post-control no hairs 100
Post-control no hairs 100
Post-control no hairs 80 20
Post-control European Rabbit Oryctolagus cuniculus 80 10 10
Post-control European Rabbit Oryctolagus cuniculus 5 95
Post-control European Rabbit Oryctolagus cuniculus 80 20
Post-control European Rabbit Oryctolagus cuniculus 50 50
Post-control European Rabbit Oryctolagus cuniculus 70 30
Post-control European Rabbit Oryctolagus cuniculus 90 10
Post-control Sugar Glider Petaurus breviceps 60 40
Post-control Greater Glider Petauroides volans 100
Post-control Greater Glider Petauroides volans 80 10 10
Post-control Greater Glider Petauroides volans 100
Post-control Mountain Brushtail Possum Trichosurus cunninghami 100
Post-control Mountain Brushtail Possum Trichosurus cunninghami 100
Post-control Echidna Tachyglossus aculeatus 95 5
Post-control Possum sp. Trichosurus sp.100
Post-control Possum sp. Trichosurus sp.100
Post-control Possum sp. Trichosurus sp.20 80
Post-control Possum sp. Trichosurus sp.80 20
Post-control Possum sp. Trichosurus sp.90 10
Post-control Possum sp. Trichosurus sp.100
Post-control Possum sp. Trichosurus sp.100
Post-control Possum sp. Trichosurus sp.90 10
Post-control Possum sp. Trichosurus sp.70 30
Post-control Possum sp. Trichosurus sp.60 40
Post-control Possum sp. Trichosurus sp.90
Post-control Possum sp. Trichosurus sp.
Post-control Possum sp. Trichosurus sp.90 10
Post-control Possum sp. Trichosurus sp.100
Post-control Possum sp. Trichosurus sp.80 20
Post-control Common Wombat Vombatus ursinus 100
Post-control Black Wallaby Wallabia bicolor 100
Post-control Black Wallaby Wallabia bicolor 70
Post-control Black Wallaby Wallabia bicolor 100
Post-control Black Wallaby Wallabia bicolor 90 10
Pre-control Dusky Antechinus Antechinus swainsonii 20
Pre-control Dusky Antechinus Antechinus swainsonii 80 10
Continued next page
46
Composition (%)
Survey Common Name Scientific Name Mammal Bird Insect Plant
Pre-control Feathertail Glider Acrobates pygmaeus 80 15 5
Pre-control Eastern Pygmy-possum Cercartetus nanus 10 90
Pre-control Eastern Pygmy-possum Cercartetus nanus 40 60
Pre-control House Mouse Mus musculus 80 20
Pre-control House Mouse Mus musculus 95 5
Pre-control Eastern Grey Kangaroo Macropus giganteus 95 5
Pre-control no hairs 100
Pre-control no hairs 100
Pre-control no hairs 100
Pre-control European Rabbit Oryctolagus cuniculus 100
Pre-control European Rabbit Oryctolagus cuniculus 5
Pre-control Sugar Glider Petaurus breviceps 95 5
Pre-control Common Ringtail Possum Pseudocheirus peregrinus 95 5
Pre-control Greater Glider Petauroides volans 100
Pre-control Sugar Glider Petaurus breviceps 80 5 15
Pre-control Swamp Rat Rattus lutreolus 100
Pre-control Swamp Rat Rattus lutreolus 100
Pre-control Swamp Rat Rattus lutreolus 80
Pre-control Swamp Rat Rattus lutreolus 95
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 100
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 90 10
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 80 20
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 80 10 10
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 100
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 80 20
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 10
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 60 30 10
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 95 5
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 100
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 100
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 90 10
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 100
Pre-control Mountain Brushtail Possum Trichosurus cunninghami 100
Pre-control Black Wallaby Wallabia bicolor 90 10
Pre-control Black Wallaby Wallabia bicolor 20 40 40
Pre-control Black Wallaby Wallabia bicolor 100
Pre-control Black Wallaby Wallabia bicolor 100
Pre-control Black Wallaby Wallabia bicolor 100
Pre-control Black Wallaby Wallabia bicolor 100
Appendix 2 continued
47
Appendix 3 Guidelines for establishing and
maintaining Red Fox control bait stations
Readers should refer to current legal and business
requirements applying to the establishment and
maintenance of bait stations within their jurisdiction.
The following guidelines are intended to assist with the
establishment and maintenance of bait stations but do not
replace the above:
1. Select sites within the designated area (see attached
maps) where foxes are likely to be active and along
thoroughfares likely to be used by foxes. Avoid locating
bait stations in areas of high public use.
2. Check supplied land tenure maps to be certain that the
bait station is located on public land and not private
freehold.
3. Bait stations must be no closer than 500m apart to avoid
bait caching. Bait stations should preferably be spaced at
approximately 1 kilometre intervals.
4. Baits must be buried according to the label at a depth of
10 cm or more. A stick coated with fish oil can be used
to help attract foxes to the bait station.
5. An area of 70 x 70 cm should be dug over or raked
around the buried bait and soil of a consistency that
allows animal prints to be detected.
6. Each bait station should be numbered with numbers
marked on cattle ear tags tied to trees above bait
stations. NB: Ensure no nails are used to fix marker tags
to avoid spreading Myrtle Wilt.
7. Each bait station should be recorded as a GPS waypoint
or the coordinates recorded and given to the PV project
manager so that their locations can be mapped.
8. Ensure all neighbours have been notified before
commencing baiting. Parks Victoria will notify
neighbours prior to commencement of each baiting
pulse.
9. Place 1080 poison baiting signs at all vehicle entry points
and other commonly used entry points immediately
before baits are laid.
10. Commence six week or appropriate pulse of poison
baiting. A stick coated with fish oil can be used to help
attract foxes to the bait station.
11. Check bait stations during poison baiting period weekly
and accurately record the following information:
• Baitstationnumberandgridreference
• Isthecurrentbaitafree-feedorpoisonbait?
• Dateandtime
• Currentweatherconditions
• Hasthebaitbeentaken?
• Isthereevidenceofanimaltracksorscatsatthebait
station? What species are they from?
• Wasthebaitreplaced?Wasitreplacedwithafree
feed or poison bait?
12. Replace baits that have been taken and if baits are not
taken for a two week period replace them with a fresh
bait.
13. At the completion of the baiting period remove all
untaken baits and dispose of them in accordance with
the ‘Directions for the Use of 1080 Pest Animal Bait
Products’.
48
January 11 2011
Media Contact:
Media Release
Native species return as predators outfoxed in Stanley State Forest
A predator control program in bushfire affected Stanley State Forest, near Beechworth, is aiding the
survival of endangered native animals by reducing fox numbers.
The program, which is set to continue into its second year, is targeting foxes.
DSE Pest Plant and Animal Management Officer, Jack Harrington, said funding to continue the control
works will directly benefit native animals.
“The Beechworth area is home to numerous threatened species, including the Brush-tailed Phascogale
and Spot-tailed Quoll,” Mr Harrington said.
“The disruption to their habitat by bushfire presents a significant challenge to their survival; and the threat
of pest animals makes it even harder.”
The Beechworth-Library Rd fire burnt through 31,000 hectares of land in February 2009, including most
of Stanley State Forest.
Mr Harrington said initial evaluation of the program found that the first round of baiting had been a
success.
“We’ve had a good number of baits taken and importantly, we’re hearing from local landholders reports
of native animals which haven’t been present in the area for some years.”
Research has shown that effective predator control requires multiple rounds of baiting if fox numbers are
to be reduced.
“The first baits were laid in this area in December 2009,” Mr Harrington said.
“We then continued baiting in 2010, and we will resume with another round this year,” Mr Harrington
said.
“By taking this intensive approach to the program, we maximise the protection of threatened species.”
Foxes and wild dogs are declared pest animals under the Catchment and Land Protection (CaLP) Act
1994. Areas treated with baits will clearly display 1080-baiting notices.
The predator control program is jointly funded by the Federal Government’s Care for our Country
program and the Victorian Bushfire Reconstruction and Recovery Authority.
For more information on bushfire recovery visit www.dse.vic.gov.au or call the DSE Customer Service
Centre on 136 186.
Appendix 4 Sample media release
www.depi.vic.gov.au