Predator Control Strategy for the Western Port Biosphere Reserve, Victoria

Transcription

1 Predator Control Strategy for the Western Port Biosphere Reserve, Project: Prepared for: Western Port Biosphere Reserve Foundation

2 2014 Ecology Australia Pty Ltd This publication is copyright. It may only be used in accordance with the agreed terms of the commission. Except as provided for by the Copyright Act 1968, no part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without prior written permission from Ecology Australia Pty Ltd. Document information This is a controlled document. Details of the document ownership, location, distribution, status and revision history are listed below. All comments or requests for changes to content should be addressed to the document owner. Bioregion: Gippsland Plain, Strzelecki Ranges, Highlands-Southern Fall Owner Author Location Ecology Australia Pty Ltd Bernadette Schmidt, Darren Quin, Jamie McMahon J:\CURRENT PROJECTS\Western Port Biosphere Reserve Predator Control \Report\WPBR Predator Control Strategy FINAL.docx Distribution Chris Chambers Western Port Biosphere Reserve Document History Status Changes By Date Draft 1 First Draft B. Schmidt, D. Quin, J. McMahon 08/09/2014 Draft 2 Updated mapping and review comments B. Schmidt, J. McMahon 19/05/2015 Final B. Schmidt 17/06/2015 Ecology Australia Pty Ltd admin@ecologyaustralia.com.au 88B Station Street, Fairfield, 3078, Australia Tel: (03) Fax: (03)

3 Contents Acknowledgments v Summary 1 1 Introduction The Growing Connections Project Objectives Project Scope Development of the Strategy 5 2 Western Port Biosphere Reserve 6 3 Pest Control in the Western Port Biosphere Reserve Current Control Programs Effective Pest Control Programs Integrated Pest Control Management Considerations and Approach Foxes Rabbits Cats 19 4 Control Areas Current Areas of Control Target Control Areas 21 5 Control Techniques Foxes Poison Baiting Den Fumigation Trapping Rabbits Poison Baiting Warren Destruction and Fumigation Cats Trapping 41 6 Monitoring Pest Monitoring Foxes Rabbits Cats Biodiversity Monitoring Occupancy Modelling Ground-nesting Birds 49 Final iii

4 7 Implementation Program Co-ordination Public Engagement and Capacity Building Geographic Information Systems Data Management 56 8 References 57 9 Glossary 62 Tables Table 1 Table 2 Pest control activities currently undertaken within the Western Port Biosphere Reserve 12 Site prioritisation criteria for fox control in the Western Port Biosphere Reserve 22 Table 3 Fauna species selected for the prioritisation of control areas 68 Figures Figure 1 The Western Port Biosphere Reserve 8 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Pest control activities currently undertaken within the Western Port Biosphere Reserve 14 Site prioritisation analysis for future control works, showing areas of varying priority within the Western Port Biosphere Reserve (combined with significance mapping from the WPBR Foundation) 25 Bait station design for buried 1080 poison baits (redrawn from Murray et al. 2006) 30 Diagrammatic representation of an M-44 ejector (taken from Ecology Australia 2013) 32 Diagrammatic representation of rabbit warren ripping (taken from Ecology Australia 2013) 40 Figure 7 Organisational Structure for the Western Port Pest Animal Group 53 Figure 8 Site prioritisation analysis for future control works, showing areas of current control and their potential area of influence within the Western Port Biosphere Reserve 69 Appendices Appendix 1 Assessment of control techniques for the Western Port Biosphere Reserve (adapted from Ecology Australia 2013) 63 Appendix 2 Sample of data recording template for fox baiting developed by the Port Phillip and Western Port Catchment Management Authority 65 Appendix 3 Multi-criteria Decision Analysis scoring system for site prioritisation within the Western Port Biosphere Reserve 66 Final iv

5 Acknowledgments The authors would like to thank the following people for their assistance in providing their time and input into the development of this project, including provision of information, data, feedback and expert opinion: Chris Chambers, David Nicholls Western Port Biosphere Reserve Foundation; John Hick Department of Environment, Land, Water and Planning; Andrew Morrison Port Phillip and Western Port Catchment Management Authority; Peter Kemp, Libby Jude, Dale Appleton, Thierry Roland Parks ; Will Steele, Gavin Brock, Paul Rees Melbourne Water; Terry Coates, Bronwyn Merritt, David Hunt Royal Botanic Gardens Cranbourne; Sam Hand, Garrique Pergl Mornington Peninsula Shire Council; Simon King Casey City Council; Rob Jones Cardinia Shire Council; Dave Martin Bass Coast Shire Council; Stuart Murphy Phillip Island Nature Parks; Nadia Arkoudis Vic Roads; Lyndal Gibbs VicTrack; Robbie Gray Bass Coast Landcare Network; Julie Trezise French Island Landcare; Kristen Skewes Bluescope Steel; Narelle Liepa Department of Defence; and Alan Robley Department of Environment, Land, Water and Planning. Final v

6 Summary This predator control strategy has been developed to support the implementation of the Growing Connections Project across the Western Port Biosphere Reserve (WPBR). The Project, which is being delivered by the WPBR Foundation, with support from the Australian Government over a five-year period, aims to protect and enhance biodiversity across the WPBR. The development of a broad-scale, co-ordinated vertebrate pest control program is seen as an essential part of achieving these aims. A number of organisations currently undertake pest control works within the WPBR. However, most of this work is limited in scope, is dependent on funding, and is generally not undertaken in a systematic or consistent manner, reducing its efficacy. The WPBR Foundation aims to establish a broad-scale vertebrate pest control program which will help integrate and co-ordinate pest control efforts across the region, to produce more efficient and effective results. This document provides the strategic framework for the establishment and implementation of a broad-scale predator control program, and guidance for agencies undertaking on-ground work, to facilitate integration and co-ordination with the Program. It applies the principles of strategic and integrated control to achieve a sustained reduction in pest populations and their impacts to biodiversity. This strategy: Focuses primarily on fox control, with a secondary focus on the management of rabbits and cats, as part of integrated pest management; Identifies control techniques that will achieve the most effective and economic control on a broad scale, based on consideration of the most appropriate and efficient techniques for each species and for the region; Provides a preliminary prioritisation of areas to target for future control works; Provides technical recommendations and protocols for on-ground works, incorporating best-practice control guidelines, to facilitate integration across the WPBR; and Specifies monitoring requirements, with recommendations for biodiversity monitoring, to align with the Growing Connections Biodiversity Monitoring program, and protocols to undertake operational monitoring to assess the efficiency of control works. The development of this strategy was informed by consultation with stakeholders currently involved with the control of invasive mammals in the WPBR, and a review of current pest control programs and conservation priorities. Collaboration and co-ordination of control efforts by various agencies, including government and non-government organisations, across the WPBR will be vital for the success of pest control efforts. As such, this strategy also provides guidelines on the implementation and management of the program into the future. It is anticipated that the recommendations in this strategy will first be adopted by the WPBR Foundation, who will drive the implement of the program, with other organisations participating and/or co-ordinating efforts in future years. Final 1

7 1 Introduction The Western Port Biosphere Reserve (WPBR) Foundation, with support from the Australian Government, is delivering the Growing Connections Project across the WPBR, over a fiveyear period to This project will see the development of key strategic documents, to guide management towards a single vision, for the protection and enhancement of biodiversity across the WPBR. As part of this project, Ecology Australia has been engaged to develop the framework for a broad-scale vertebrate pest control strategy, aimed at integrating and coordinating pest control efforts across the region, to produce more efficient and effective results. This strategy is intended to provide the basis for a large-scale, collaborative, cross-tenure program, which seeks participation from government, land management agencies, conservation and community groups, research institutions and private landholders. 1.1 The Growing Connections Project The Growing Connections Project aims to protect and enhance biodiversity, and create a more resilient environment within the WPBR. To achieve these aims, the WPBR Foundation has committed to undertaking a number of co-ordinated actions, which include: Development of the Growing Connections Biodiversity Plan (WPBRF 2015), integrating scientific information with community participation, to create a more resilient environment; Re-vegetation activities to improve the quality and extent of native vegetation; Development of a broad-scale predator control program for the WPBR, with a robust monitoring program; Establishment of enabling systems to enhance and improve management; Development and implementation of a broad-scale biodiversity monitoring program, to be integrated with the monitoring for the pest control program; and Creation of an integrated Geographic Information Systems (GIS) environment for the WPBR. Western Port Biosphere Reserve Pest Control Program The development of a broad-scale, co-ordinated vertebrate pest control program is seen as an essential part of helping to achieve the aims of the Growing Connections Project. The detrimental impacts of introduced species, particularly introduced mammals, on Australia s biodiversity have been well documented (e.g. see Saunders et al. 1995, Williams et al. 1995, Dickman 1996) and are recognised as Key Threatening Processes under both Federal and State Environmental Legislation. These include the following listings under the Federal Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act): Predation by the European red fox; Predation by feral cats; and Competition and land degradation by rabbits. Final 2

8 Predation by the European Red Fox (Vulpes vulpes) and Feral Cat (Felis catus) has been implicated in the extinction and widespread decline of numerous native wildlife species, including many small to medium-size mammals, birds and reptiles, as well as the failure of threatened species recovery and re-introduction programs (Dickman 1996, Short et al. 1992, DEWHA 2008a, b, Saunders et al. 2010). Foxes are also an important predator of livestock, and a significant agricultural pest (McLeod 2004). Predation impacts on wildlife are generally greatest in fragmented landscapes, where native species are largely restricted to vegetation remnants and in modified environments where an abundance of resources support large predator populations (Mahon 2001, Saunders and McLeod 2007). Densities of foxes can be particularly high in urban and agricultural areas which provide a plentiful supply of food and natal den-sites, while large populations of cats are typically found around areas of high human habitation, where domestic cats continually supplement the stray and feral cat populations (Denny and Dickman 2010). The direct impacts of European Rabbits (Oryctolagus cuniculus) on soils and vegetation, due to grazing and burrowing activity, are also well recognised. They include soil erosion, alteration of vegetation structure, prevention of regeneration, and facilitation of weed invasion, which can impact on wildlife habitats. However, rabbits also threaten wildlife through their potential interaction with predator populations; large rabbit populations can support and facilitate the recovery of introduced predator populations, such as foxes and feral cats, for which rabbits constitute a major source of prey (Catling 1988, Smith and Quin 1996). A number of government agencies and non-government organisations in the Western Port Region are currently undertaking activities to control foxes, cats and rabbits on public and private land. These programs have been implemented as part of a major effort by land managers, over the past five years in particular, to control vertebrate pests to improve biodiversity values and agricultural productivity in the region. However, they are generally restricted in scale and scope, due to funding and resources, and there is currently limited coordination between programs, in terms of control methods and protocols, timing and spatial coverage, which limits their potential efficacy and benefits. Successful control programs require a collaborative and co-ordinated approach (Saunders and McLeod 2007). 1.2 Objectives The WPBR Foundation aims to establish the framework for a landscape-scale, co-ordinated predator control program, which will guide the integration of current and future pest animal control activities, undertaken by local agencies across areas of both public and private land around Western Port Bay. This approach is modelled on the principles of the Ark programs operating across, which include: Southern Ark, Grampians Ark, Glenelg Ark and Central Highlands Ark. These programs are major initiatives by the n Department of Environment, Land, Water and Planning (DELWP), which aim to facilitate the recovery of native wildlife through broad-scale fox control. The programs have joint management and research components, undertaken through collaboration between government agencies, research institutions and the Invasive Animals Cooperative Research Centre (CRC). Some of these programs, such as the Southern Ark, operate across vast areas of public land, predominantly State Forest and Final 3

9 National Park, while others, such as the Grampians Ark extension program, in the Valley, Halls Gap, extend into areas of private land. The predator control strategy for the WPBR aims to achieve two major outcomes as part of the Growing Connections Project: Establishment of a Western Port Pest Animal Group, to facilitate the co-ordination, implementation and operation of the program, by various agencies, across the landscape, and to drive innovation and improvement in best practice pest control; and A target of 9,086 ha of land, managed for invasive mammal species, with approximately 125 ha directly funded by the WPBR Foundation. This predator control strategy facilitates a co-ordinated response to pest animal control by providing guidance on the most appropriate pest control techniques and on-ground protocols, for agencies that participate in the Western Port Pest Animal Group. The strategy also provides guidance on the areas for predator control, broadly highlighting areas where predator control activities may be most feasible and effective, and where other conservation works are being undertaken as part of the Growing Connections Project. The strategic approach recommends an initial focus on foxes and rabbits, with monitoring to determine the potential impacts of predation by feral cats, and the need for control of cat populations. A monitoring program will be implemented as part of this program, specifically to monitor predator populations and the effectiveness of predator control, but also the responses of prey populations. The program will be designed to complement, and run in parallel to the Biodiversity Monitoring Program, using an array of motion-sensing cameras to help determine the relationship between predators and prey. 1.3 Project Scope This project is aimed at developing a broad-scale approach to predator control, through collaboration, and improving the integration of pest control programs throughout the WPBR, to produce more effective results. Specifically, the objectives of this project are to: Develop a strategic, integrated approach to predator control, which identifies the most effective control techniques and the most appropriate techniques for the landscape; Develop best-practice protocols for the delivery of on-ground pest control, to be followed by contractors when undertaking control works, to integrate pest control practices across the WPBR, and facilitate co-ordination; Identify areas where predator control activities are likely to be most effective and of most benefit to biodiversity, to provide priority areas for management agencies to investigate for future works; Align this project with the Integrated Predator Control Strategy for the Southern Brown Bandicoot in the south-east sub-region developed for DEPI as part of Melbourne s Strategic Assessment of the growth areas (Ecology Australia 2013); and Facilitate the first convention of agencies and groups undertaking pest control in the region, which will provide the basis for the formation of the Western Port Pest Animal Group. Final 4

10 1.4 Development of the Strategy The development of this strategy was informed by consultation with stakeholders currently involved with the control of invasive mammals in the WPBR, and a review of current pest control programs and conservation priorities. A workshop was held on 17 February 2014, at the Royal Botanic Gardens Cranbourne, to elucidate current patterns of control and techniques used across the WPBR, the objectives of various pest control programs, the limitations and opportunities for integration into a broader program. The workshop gathered together key stakeholders (see Acknowledgements) to share information, and also served as the first meeting of agencies which may be involved in the future integration and implementation of pest control works in the WPBR. Information provided during consultation with stakeholders, and GIS, was used to identify areas currently managed for pest animals, and to identify and prioritise areas in which to undertake pest control works in future, under the Growing Connections Program. GIS was used to analyse the spatial coverage of control works and potential areas for control, with the aim of maximising the effectiveness of control across the landscape. Control techniques selected include those which are currently employed by some agencies, and on the basis of an assessment of the most effective, efficient and appropriate techniques for the region. Where possible, the strategy has been developed to co-ordinate with other major pest control programs currently being undertaken or planned for the region, including the Ramsar Protection Program (see Section 3.3) and the Integrated Predator Control Strategy for the Southern Brown Bandicoot. The Strategy has been reviewed by the WPBR Foundation and key stakeholders, at two subsequent workshops held by the WPBR Foundation. Final 5

11 2 Western Port Biosphere Reserve The Mornington Peninsula and Western Port region was declared a Biosphere Reserve by the United Nations Educational, Scientific and Cultural Organisation (UNESCO) in 2002, in recognition of the region s significant biodiversity values, which include the Western Port Ramsar site (a wetland of international importance). Biosphere Reserves are internationally recognised under UNESCO s Program on Man and the Biosphere, aimed at promoting a balanced relationship between humans and the biosphere. They typically include urban, industrial and agricultural areas as well as conservation reserves. The WPBR is located on Melbourne s urban fringe, approximately 50 km south-east of Melbourne. It covers c km 2 over five Local Government Areas around Western Port Bay, in south-central, including the Cities of Frankston and Casey and Shires of Cardinia, Bass Coast and Mornington Peninsula, which have agreed to operate as though the Reserve extends to the limit of their boundaries (Figure 1). It includes areas of urban development, light and heavy industry (e.g. oil refinery and steel works), agricultural areas (primarily horticulture, grazing and dairying), and areas of terrestrial and marine conservation significance. The Western Port region also supports a number of other uses, including shipping, recreational boating, fishing, tourism and aquaculture. Development in the region has resulted in extensive modification of the natural environment since European settlement, which has included land clearance, the drainage of swamps and wetlands, and the introduction of weeds and vertebrate pests. Much of the region supports productive agricultural land, and the vast majority has been cleared of native vegetation: Today, only small remnants remain in relatively isolated conservation reserves. Despite its modified nature, the WPBR supports significant natural values, including important conservation areas and threatened species, particularly within the rural landscape. These include: The Western Port Ramsar site (listed under the Convention on Wetlands of International Importance, Ramsar 1971), recognised for its significant flora, fauna, cultural and scenic values, including the wide range of terrestrial and wetland habitats, and number and diversity of waterfowl and migratory shorebirds (KBR 2010); National Parks, including Yaringa, French Island and Churchill Island Marine National Parks and French Island and Point Nepean National Parks; State Parks, including Arthur s Seat State Park and Bunyip State Park; Sites of zoological significance, including breeding colonies of the Little Penguin (Eudyptula minor), Koala (Phascolarctos cinereus), Australian Fur Seal (Arctocephalus pusillus doriferus), Hooded Plover (Thinornis rubricollis) and Shorttailed Shearwater (Puffinus tenuirostris); Threatened flora and fauna species and vegetation communities, including one of the five n sub-populations of the nationally-listed Southern Brown Bandicoot (Isoodon obesulus obesulus); and Numerous sites of geomorphological significance and scenic landscape values. Final 6

12 The majority of WPBR falls within the western portion of the Gippsland Plain Bioregion, with small sections extending into the Strzelecki Ranges Bioregion in the north-west, and the Highlands-Southern Fall Bioregion in the north. The region is characterised by a temperate climate of cool, wet winters and warm, dry summers. UNESCO Biosphere Reserves remain under the jurisdiction of the State in which they are located. The WPBR Foundation was established in 2003, as a non-profit organisation, to implement the UNESCO program. The Foundation works with the n Government, Local Government Authorities, the community and UNESCO, to create a sustainable future for the Western Port region, environmentally, socially and economically. It does this through research, education, community engagement, partnerships and on-ground conservation efforts. Final 7

13 Figure 1 The Western Port Biosphere Reserve Final 8

14 3 Pest Control in the Western Port Biosphere Reserve 3.1 Current Control Programs A number of land managers currently undertake pest control works within the WPBR, including government agencies, conservation and community groups, state-owned corporations and private industry (see Table 1). These works reflect a growing recognition of the threats of invasive species to both biodiversity and agriculture in the region, and an increasing investment in reducing these threats. However, much of this work is not undertaken in a systematic or consistent manner, and relies on limited, short-term funding, which undermines its efficacy. This means that control programs are not necessarily undertaken across multiple years or at the same sites each year. Information on control activities undertaken between 2013 and 2014 was provided by stakeholders at the workshop and during individual consultations. A summary of those works, undertaken is provided below, with further details provided in Table 1. Table 1 includes only those activities for which detailed information was readily available; their spatial configuration shown in Figure 2. Figure 2 presents a static representation of works being undertaken in the region, and represents the best information available at the time. However, due to the typically limited nature of funding and resources, it is likely that some of these programs may continue in subsequent years, while others may not. Patterns of Control Most control activities in the WPBR are undertaken independently and over a relatively small scale, with limited co-ordination or consistency between and/or within organisations, in terms of control methods, protocols, timing or frequency of control (see Table 1). While some land managers have made notable efforts to adopt a more co-ordinated approach, through partnerships and participation in State- or Federally-funded biodiversity programs (see below), many undertake control on a reactive or ad-hoc basis, particularly those organisations for which pest control, for biodiversity protection or agriculture, is not a primary responsibility. Additionally, limited and short-term funding places constraints on the level of resources which can be allocated to pest control, and the intensity and frequency with which control programs can be undertaken; the ability to overcome these restrictions in future is likely to be limited. Integrated Pest Control Despite the occurrence of multiple pest species within the WPBR, few organisations undertake control for more than one species. Most control works are targeted towards foxes, and to a lesser extent, rabbits; although resources for rabbit control are usually directed towards providing support to landowners, rather than on-ground works (see Table 1). This work is mostly undertaken by Landcare groups, which co-ordinate initiatives such as the Rabbitbusters program, targeted to agricultural landholders. Annual rabbit control has only been undertaken at one site, managed by the Department of Defence. Regular cat control is undertaken only on French Island and Phillip Island, and at a small number of sites on the Mornington Peninsula. Very little is known about cat populations and the need for cat control on the mainland, although a number of organisations reported frequently seeing feral cats on Final 9

15 their land. Some government agencies have also undertaken localised control of deer, hares, rats and cats, and initiatives on responsible pet ownership have been developed by Councils and Landcare Groups. Control Techniques Various methods have been used to control foxes across the WPBR, including poison baiting, soft-jaw trapping, den fumigation and shooting. Of these, poison baiting is the most commonly used technique, followed by soft-jaw trapping; trapping is typically employed in areas where baiting is not permitted or there is public opposition. Despite the prevalence of poison baiting as a control technique in the WPBR, the standards and protocols adopted, in terms of the materials used (e.g. bait type, attractants), frequency, duration and timing varies between organisations/ programs (see Table 1). On-ground works are undertaken by various different contractors, with differing methods of deploying and replacing baits. In addition, most baiting is undertaken too infrequently or over a too short of a time period to provide effective or longterm control. Only those organisations that participate in a co-ordinated program undertake baiting four or more times per year (see Table 1). Co-ordinated Programs and Partnerships The Ramsar Protection Program, co-ordinated by the Port Phillip and Westernport Catchment Management Authority (PPWCMA), is one of the few programs in the region in which participants have attempted co-ordinated and strategic control of pests, for the protection and enhancement of Ramsar values (and other biodiversity values) around Western Port. This program, which includes participation by the WPBR Foundation, Parks, Mornington Peninsula Shire, Cardinia and Bass Coast Shire Councils, City of Casey Council, Phillip Island Nature Parks and Landcare networks, involves poison baiting, usually under a continuous deployment regime, on numerous parcels of public land managed by participating agencies, as well as soft-jaw trapping, where baiting is not considered feasible. As part of this program, the WPBR Foundation has invested significant effort in engaging individual landowners to undertake baiting on private agricultural land. Funding for this program is on a five-year basis and has recently been renewed. Parks also maintains various partnerships with other land management organisations in the region, including Melbourne Water, Phillip Island Nature Parks and French Island Landcare Group, in addition to independently undertaking control works in various parks and reserves (Figure 2). Parks are guided by a strategic framework developed for the prioritisation of pest control across their parks and reserves system (Robley and Choquenot 2002), along with a series of threat monitoring protocols. However, they also undertake works outside of this framework as part of collaborative or good neighbour programs and the extent to which the protocols are implemented varies. A small number of areas within the WPBR with conservation significance, including the Royal Botanic Gardens Cranbourne, Phillip Island, French Island and Bandicoot Corner, are also subject to individual management protocols. These areas are managed independently, in accordance with specifically development management plans. Final 10

16 The largest, most comprehensive and long-term control program in the WPBR is undertaken at Phillip Island. Phillip Island Nature Parks has undertaken fox control at Phillip Island for the past 30 years, using localised baiting, trapping and spotlight shooting, but since 2007 have shifted their focus to the eradication of foxes from Phillip Island, using broad-scale baiting (McPhee and Bloomfield 2012). It is now estimated that there are less than 10 foxes on Phillip Island; remaining animals will be targeted with the aid of detection dogs (S Murphy, Phillip Island Nature Parks, pers. comm.). Genetic material collected over the past 15 years shows that there is likely to be very little immigration of foxes from the mainland to Phillip Island, and Phillip Island Nature Parks, in partnership with Parks, are now working on fox control in a buffer zone around San Remo and Anderson Inlet to assist with eradication. Cat trapping is also undertaken across much of the island, together with opportunistic shooting of feral cats in conservation areas, while rabbit control is mostly implemented by local landowners with the aid of the Landcare Group, but not in a systematic way. Monitoring Most of organisations undertake little or no monitoring of the success of control activities, in terms of ecological outcomes. Most monitoring is operational, involving only the collection of data on bait-take or catch-per-unit-effort, although, many programs lack standard reporting mechanisms, and reporting of results is often inconsistent between contractors. In some cases, there appears to be no formal documentation of the work undertaken. The most comprehensive monitoring programs are implemented by the Royal Botanic Gardens Cranbourne, WPBR Foundation and Phillip Island Nature Parks. The WPBR Foundation has recently commenced monitoring of Southern Brown Bandicoot responses with motion-sensing cameras and a sampling design which will allow occupancy modelling to be undertaken (see Section 6.2). Melbourne Water and VicRoads have also recently begun to use motion-sensing cameras to monitor the presence or absence of predator and prey species in their management and works areas. Limitations to Effective Control For many organisations, especially where land management does not form part of their core business, the major impediments to undertaking effective pest control appear to be due to limited in-house expertise, a lack of resources and limited capacity to undertake control works outside of their daily operations, or beyond the boundaries of their land. Co-ordination of pest control efforts across the region aims to assist with maximising the benefits of pest control by pooling resources and standardising techniques to achieve a sustained reduction of pest species and their impacts and ensuring that ecological outcomes can be better evaluated. For many land managers, however; limited funding and resources to undertake continuous and broad-scale control is a major limitation. While the coordination of pest control efforts will assist to some extent, lack of funding will continue to be a limitation which may influence the extent and scale at which some of the recommendations can be implemented. Final 11

17 Table 1 Pest control activities currently undertaken within the Western Port Biosphere Reserve Management Agency Control Program Collaborations Control Method Frequency Duration Timing Locations Monitoring Fox Control Royal Botanic Gardens, Cranbourne Independent Poison baiting Continuous n/a n/a Royal Botanic Gardens Cranbourne Bait-take, sand-pads, motion-sensing cameras Western Port Biosphere Reserve Natural Resource Investment Program: Recovery Actions for the Southern Brown Bandicoot Poison baiting Continuous n/a n/a Private property; various locations (former Koo Wee Rup Swamp area) Motion-sensing cameras predator and prey occupancy modelling Parks Ramsar Protection Program Poison baiting??? Quail Island and Warneet, Yaringa, northern Western Port inlets, Bass River/Reef Island Independent Soft-jaw trapping??? Langwarrin Flora and Fauna Reserve, The Pines Flora and Fauna Reserve Independent???? Bunyip State Park, Point Nepean National Park, Wonthaggi Heathlands Bait-take Catch-per-unit-effort X Phillip Island Nature Parks Poison baiting 3-4 X per year 6 weeks Variable San Remo, Anderson Inlet? Melbourne Water Bunyip Main Drain bank stabilisation works Poison baiting 2 X per year 2 weeks Variable Bunyip Main Drain Bait-take, motion-sensing cameras Independent The Inlets at Koo Wee Rup Fauna trapping, motion-sensing cameras at bait stations Independent Soft-jaw trapping Once (2009, 2010, 2013) 20 days Autumn Edithvale Wetland Catch-per-unit-effort Once (2014) 11 days Autumn Seaford Wetland Catch-per-unit-effort Mornington Peninsula Shire Council Ramsar Protection Program Poison baiting 2 X per year 2-9 weeks Late-summer, late-winter Briars Park, Peninsula Gardens, Woods Reserve? Independent Soft-jaw trapping 2 X per year 1-2 weeks Late-summer, late-winter Various, Mornington Peninsula Catch-per-unit-effot VicRoads Koo Wee Rup Bypass Southern Brown Bandicoot protection Poison baiting 2 X per year 6-8 weeks May-July; August-September Private property: Koo Wee Rup Rd and Rossiter Rd, Koo Wee Rup Bait-take, motion-sensing cameras VicTrack Independent Soft-jaw trapping Ad-hoc - - South Gippsland Railway - Bluescope Steel Independent Poison baiting Annual 6 weeks Various contractor discretion Bluescope Steel, Hastings Bait-take Cardinia Environment Coalition Independent Poison baiting??? Bandicoot Corner, Bayles? Bass Coast Landcare Independent Shooting On request 2-3 days Spring autumn Private land: various - Department of Defence Independent Poison baiting As needed Variable Variable HMAS Cerberus, Crib Point - Phillip Island Nature Parks Parks, Bass Coast Landcare Poison baiting 4 X per year 4 weeks August, November, March, May Phillip Island Motion-sensing cameras, spotlighting, public sightings Linking Melbourne Authority Peninsula Link SBB offset???? Adams Creek Nature Conservation Reserve, Wonthaggi Heathlands? Cat Control Parks Ramsar Protection Program Cage trapping Annual 10 weeks June- August French Island, northern Western Port inlets, Quail Island and Warneet Catch-per-unit-effort French Island Landcare Parks Cage trapping Annual 10 weeks June-August French Island Catch-per-unit-effort Mornington Peninsula Shire Council Independent Cage trapping 2 X per year 1-2 weeks Late-summer, late-winter Various, Mornington Peninsula Catch-per-unit-effort Final 12

18 Management Agency Control Program Collaborations Control Method Frequency Duration Timing Locations Monitoring Bass Coast Landcare Phillip Island Nature Parks Cage trapping Annual?? Phillip Island Catch-per-unit-effort Phillip Island Nature Parks Phillip Island Shooting opportunistic - - Phillip Island - Rabbit Control Melbourne Water Independent Poison baiting Once (2009, 2014) 21 days Autumn Edithvale Wetland Rabbit carcass collection Parks Independent???? Bass River/Reef Island Motion-sensing cameras Bass Coast Landcare Independent Poison baiting, Shooting On request weeks Late-summer, early autumn Phillip Island Private land: various Spotlight monitoring French Island Landcare Independent Poison baiting (support to landholders) On request - - French Island - Department of Defence Independent Poison baiting Annual Variable Variable HMAS Cerberus, Crib Point - Final 13

19 Figure 2 Pest control activities currently undertaken within the Western Port Biosphere Reserve Final 14

20 3.2 Effective Pest Control Programs Effective pest control programs are broad-scale and strategic, particularly with regard to determining priority areas for control, the timing and frequency of control and range of techniques, so as to achieve the maximum benefit for the control effort. The control of introduced pests, particularly foxes, is undertaken across Australia, for the protection of both biodiversity and agriculture. However, pest reduction is often undertaken by individual landowners or community groups, based on the biology of the species being protected, rather than the pest species. As a result, pest control is typically localised and sporadic, leaving large areas or periods of time where pests are not subject to control, allowing them to recover quickly due to re-colonisation from adjacent uncontrolled areas (Reddiex et al. 2006, Saunders and McLeod 2007). The scale of control efforts should match the spatial extent of the impact and movements of pest species. As most pest species are highly mobile and capable of quickly replacing animals killed in control operations, achieving broad-scale, coordinated control is vital to a successful program. The importance of collaborative control efforts, for achieving broad-scale pest control was described by Saunders et al. (1995), who emphasised the need for promoting community ownership of the issue. This is particularly important for regional, cross-tenure programs, as has more recently been demonstrated by programs, such as the Benalla Carpet Python Fox Control Program in and the Outfox the Fox and North Sydney Regional Fox Control Programs in New South Wales, which have invested heavily in community engagement and capacity building. An effective control program also requires an integrated approach which considers the ecology and interactions between species, especially predator and prey. Traditionally, pest control programs in Australia have focused on one pest species, even though multiple species typically co-occur; this ignores potential interactions between pest species and their impacts, and implications for biodiversity (Reddiex et al. 2006). The importance of integrated pest control programs is outlined below Integrated Pest Control Integrated pest control is an ecosystem-based approach to pest management, which recognises the interactive relationships between plant and animal species, both introduced and exotic, as well as the influence of environmental factors. Integrated pest management strategies are based on knowledge about the lifecycles of pest species, and their interactions with other species, and typically comprise a combination of techniques which provide effective and economical control, with minimal risk to the environment, agriculture or people. Integrated pest control is an important consideration, particularly in environments supporting more than one pest species, and where overlap in the ecology of pest species may lead to an interaction between their negative impacts. Overlooking these relationships can have serious negative implications for native fauna, because the lethal control of one pest species can influence the abundance or distribution of another. For example, the effective control of fox populations can significantly reduce predation pressures on rabbits, which are known to provide a substantial component of the fox diet (Catling 1988, Banks et al. 1998, Saunders and Final 15

21 McLeod 2007). A resultant increase in the rabbit population may impact wildlife through mesopredator release (see below), or through competition and habitat degradation. Conversely, control of rabbit populations in the absence of fox control could lead to prey switching by foxes, thereby increasing predation pressures on native fauna (Robley et al. 2004). Mesopredator Release Mesopredator release theory suggests that subordinate predators (i.e. mesopredators) can have a substantial negative impact on prey populations, following their release from competition or predation pressure from the dominant predator (Johnson et al. 2007, Sutherland et al. 2010). The release of a mesopredator has typically been interpreted as an increase in abundance of the mesopredator, but can also relate to an increase in distribution or density, or a change in behaviour, such as an increased ranging behaviour (Molsher 1997, Prugh et al. 2009) In Australia, this type of interaction mostly occurs between foxes and cats due to their overlap in distribution and diet (Saunders and McLeod 2007). Rabbits are known to provide the dietary staple of both species, with each preying on different age-classes of rabbits, and consuming different supplementary prey (Catling 1988). The predator-prey relationship between foxes, cats and rabbits is complex, and not yet fully understood, with factors, such as habitat type, food availability, season and rainfall, and disease also influencing population responses (Robley et al. 2004). As a result, the evidence for mesopredator release in Australia is inconsistent (Robley et al. 2004). However, a number of studies have indicated that the abundance of feral cats can increase significantly if foxes are effectively controlled, leading to a decline in native mammal populations (Algar and Smith 1998, Short et al. 1999, Risbey et al. 2000, Catling and Reid 2003, Invasive Animals CRC 2009, Woodford 2012). Further research is required to better understand these relationships. 3.3 Management Considerations and Approach This strategy focuses primarily on the control of fox populations within the WPBR, and secondly on rabbit populations. Although few studies have formally assessed the interactions between introduced predators and rabbits (particularly in temperate environments), a number have shown that predator control allows large and rapid increases in rabbits, to the extent where they can escape regulation, even after predator populations recover (see Robley et al. 2004, Saunders et al. 2008). The implications of this for mesopredator release are uncertain. However, this strategy promotes a risk-averse approach, with protocols provided for fox and rabbit control, as well as for monitoring and control of cat populations, which may be implemented as necessary. The benefits of this control program to biodiversity values will depend on whether the level of pest impacts can be reduced to a degree that will allow native wildlife populations to increase. There is presently no known consistent relationship between pest density and the level of impact, thus, the level of control which will be required is unknown. Determining the precise nature of the relationship between pest density and damage is difficult because these relationships are often density-dependent and there are numerous confounding factors. The WPBR Foundation is currently implementing a camera monitoring program which aims to elucidate the relationship between foxes and Southern Brown Bandicoots; this may provide some guidance in future, but the results of this research are not yet available. Final 16

22 In the absence of this information, this strategy is based on the assumption that a decline in pest abundance is directly related to a decline in pest impact. This means that in order to achieve a decline in the fox population, the rate of removal of individuals must be higher than the intrinsic rate of increase (r m ) of the population (Hone 1999, Hone 2007). These rates have been calculated for foxes and rabbits in Australia (Hone 1999). However, there is no information on the current abundances or densities of pest species within the WPBR. This strategy applies the principles of strategic and integrated control to achieve a sustained reduction in pest populations and consequently, their impacts: Areas for future pest control works have been strategically identified to target areas where control works may be most feasible and effective, to reduce the potential for immigration and recolonisation of pest species, and to align with other conservation works undertaken for the Growing Connections Project; Control measures have been selected to achieve the most economical control on a broad-scale, using a combination of techniques, as appropriate, across various land uses; and The control strategy should minimise the need to cull large numbers of animals on a regular basis. This means that control needs to be sustained so that population densities remain low. This necessarily emphasises a control program which is based on the ecology of the pest species. Management considerations for each pest species addressed in this strategy are outlined below Foxes Foxes are highly mobile, and have a high dispersal capability and high reproductive capacity. Therefore, populations which have been subject to control are capable of quickly compensating for population reductions through immigration, increased survival or fecundity (Thomson et al. 2000, Hone 2007). Areas where fox populations have been substantially reduced, act as sinks which continually draw-in foxes from surrounding areas, as territories are vacated. This means that fox control must be undertaken over large areas, to reduce immigration from uncontrolled areas as far as possible, and at relatively high frequency, to avoid temporary, but damaging peaks in the population. Additionally, the level of fox control must take into account the potential compensatory increases in survival and fecundity; following an initial decrease in the fox population, more resources are available to remaining individuals, which can lead to the increased growth rate of the population. Hone (1999) estimated that approximately 65% of the fox population needs to be removed annually, to offset the higher growth rates that may be a compensatory response for the population. Most successful fox control programs have calculated initial (knock-down) reduction of between 75% and 99% of the population (based on calculated rates of bait-take). This requires a control technique which can be economically and efficiently implemented on a broad scale, and is capable of removing large numbers of animals from the population. Final 17

23 The rate of removal can have a greater impact if control is targeted to the proportion of the population which contributes most to the next generation (Hone 2007). In fox populations, the youngest age-classes (birth 2 years) have been found to make the greatest contribution to the finite rate of increase, with the influence of survival being nearly as high, or in some cases, higher (McLeod and Saunders 2001). Therefore, management strategies which target both recruitment and survivorship are likely to be the most effective for reducing the rate of increase in fox populations (Saunders and McLeod 2001, Hone 1999). An assessment of fox control techniques is given in Appendix 1, and techniques recommended for the WPBR are discussed in Section Rabbits Rabbits have a high reproductive rate, are extremely fecund, have a high rate of dispersal, and are capable of colonising a wide range of habitats (Williams et al. 1995). Thus, collaborative and sustained control is equally as important for rabbits as it is for foxes, providing the most efficient and economical means of rabbit control (Williams et al. 1995, DEWHA 2008c). Effective rabbit control requires a combination of methods, using direct, broad-scale control to achieve an initial reduction in the population, followed by supplementary methods that reduce habitat suitability and breeding activity, to ensure the long-term control of rabbits and their impacts. Without follow-up control, rabbits will readily recolonise control areas and/or increase their population growth rate (Williams et al. 1995). An assessment of available rabbit control techniques is provided in Appendix 1, and protocols for the most effective techniques are given in Section 4.2. Rabbit populations have a high intrinsic rate of increase; it has been estimated that preventing population growth requires the removal of approximately 87% of the rabbit population, annually (Hone 1999). To attain the largest population reductions, and gain the maximum benefits of control, it is best to target rabbit populations when density is naturally lowest, based on the seasonal cycles of rabbit biology. This can significantly improve the economy and humanness of the control program, reducing the effort required for subsequent control (Williams et al. 1995). Little is known about rabbit populations within the Western Port region in terms of their distribution, density or areas of greatest impacts. Typically, the distribution and density of rabbits is thought to be influenced by soil type and land use; rabbits require warrens and above-ground surface harbour not only for shelter, but also to breed. Warrens in particular, significantly enhance the survival of young (Williams 1995, Bloomfield 1999a, b). For this reason, rabbits are thought to prefer areas with deep, well-drained or sandy soils. Anecdotal evidence suggests that rabbits within the WPBR may also rely heavily on above-ground harbour. However, the sandy soils around the former Koo Wee Rup Swamp, particularly around the waterways and drains, may be particularly suitable for burrowing, and support higher rabbit densities. Potentially suitable areas could be identified with GIS, followed by onground survey to identify areas of high rabbit density or impact (see Section 6.1.2). These areas could be targeted as a priority for rabbit management in the WPBR. Final 18

24 3.3.3 Cats The management of cats in urbanised and agricultural landscapes is problematic because of their status as both a pest and domestic pet; cats may be classed as domestic, stray or feral, and may move between these categories across their lifetime (Moodie 1995). Cat densities are also generally elevated in these environments, because they are resource-rich and the domestic cat population provides a continual source of supplementation to the feral cat population. Densities of feral and stray cats in the region are not known, but research has shown that cat densities in particular areas may change in response to the local distribution and availability of food resources (Denny and Dickman 2010). The role of rabbit populations in influencing cat distribution and density is not known. The WPBR has a number of areas which may support a high density or source populations of cats. They include industrial areas, rubbish tips, old quarries, dairy farms and tourist resorts in coastal areas. These areas have often been found to support local, structured colonies of stray and feral cats, from which cats disperse into surrounding areas, including conservation areas (Denny 2005, Denny and Dickman 2010). Monitoring of cat populations within the WPBR should be undertaken to identify areas of high cat density and to evaluate population changes. Focusing on these areas, as a priority for monitoring, and subsequent control if necessary, would help to target and improve the efficiency of cat management in the WBPR. Where monitoring suggests that there are likely to be adverse impacts to native wildlife, cat control could be undertaken, although, the level at which cat populations are likely to cause significant negative impacts to native species is not known. The options available for cat control in are limited, due to the high risk of non-target impacts to domestic cats and native wildlife. Therefore, cat control will necessarily rely on localised control, using non-lethal methods, in high-density areas or those supporting likely source populations of feral and stray cats. An assessment of the relative benefits and suitability of available cat control techniques is given in Appendix 1. Those techniques recommended for the WPBR are discussed in Section 4.3. Final 19

25 4 Control Areas The area of focus for this strategy is centred to the north of Western Port Bay, encompassing areas of high conservation value within the WPBR, and areas where the majority of control activities are currently being undertaken (see Figures 2 and 3). Within this area, a prioritisation framework has been developed, using GIS and a multi-criteria decision analysis, to provide strategic direction on areas to target for future control activities. The analysis takes into consideration current areas of control and their spatial coverage, conservation values and feasibility of control under various land uses, to identify areas where pest control works are likely to be most feasible and most effective. The prioritisation of sites is provided only for fox control, primarily as foxes are the main focus of this strategy and of current control activities, but also because further information is required prior to implementing rabbit or cat control works across the WPBR. 4.1 Current Areas of Control Areas where fox control activities have been most recently undertaken have been used as the basis for the prioritisation of target areas. Future control activities and the areas in which they are undertaken should build on these control activities, to optimise the spatial coverage of fox control. Areas of land currently managed for foxes were mapped using GIS, based on the locations of control activities provided by various organisations, as shown in Figure 2. This included poison baiting as well as leg-hold trapping. Only those locations at which control activities are likely to be ongoing, and where there is potential for co-ordination with the Growing Connections Program, were used in the analysis; these included works undertaken as part of the Ramsar Protection Program, and areas for which agencies such as Parks, Melbourne Water and VicRoads have future funding. Once-off control activities, those undertaken on an ad-hoc basis, or those for which future funding has not been secured, were not included. The data provided by some organisations comprises point locations (for traps or bait stations), while other organisations have defined polygons within which control works are undertaken; in some cases this has been defined by the site boundary, but in other cases appears to arbitrarily defined. For each of these locations, the potential area of influence was mapped by applying a 1-km buffer around point locations or the boundaries of polygons. The potential area of influence is based on research undertaken as part of Project Deliverance in east Gippsland, which estimated the area of effect for bait stations to be 1600m; conservatively, 1 km (Murray et al. 2006). Although undertaken in a forested landscape, this research is generally used as the basis for the widely used 1-km spacing between bait stations in many regional control programs, in the absence of better information. Isolated control locations (i.e. separated from another location by more than 1 km) were not used in the analysis, because these are generally not considered to be effective. Final 20

26 4.2 Target Control Areas Management Units The area around Western Port was divided into 1-km grid cells using GIS (see Figure 6), to assist with future management and analysis. These landscape units have been used to guide the first stage of the prioritisation process. Under the prioritisation framework (see below), each grid cell has been assigned a priority rating to refine the selection of future fox control areas. The second stage of the selection process will involve the identification and selection of specific land properties or land parcels, within which to undertake future control works, and will require agreement for participation and collaboration with the land owner or land manager. The assigned priority ratings provide a hierarchy of areas to target for further investigation, which may involve on-ground assessments of potentially suitable areas and discussions with potential participants. The 1-km grids cells can also assist with an assessment of baiting density, where mapping of bait stations within the grids can be used to calculate the number of baits per square kilometre. Site Prioritisation Framework Ideally, fox control within the WPBR would be implemented so that there is an even distribution of poison baits across the landscape, with little or no gaps between baited areas, and over as large an area as possible. However, in reality, fox control efforts are restricted by factors such as: funding and resources, which limit the number of baits that can be laid; willingness for participation by the wider community; and the feasibility of poison baiting within different land uses, particularly in the first years of a control program. Therefore, the initial selection of areas for fox control should strategically target areas that build on current control activities, protect natural values and where land tenure and uses are amenable to control activities, such as baiting, including large public or private land holdings (e.g. quarries, golf courses). A multi-criteria decision analysis was used to prioritise areas across the WPBR, to target for fox control. GIS was used to analyse the spatial coverage of current control works and to prioritise areas for future control works. The process considered five criteria, which included: Spatial coverage of current control areas; Extent of remnant vegetation; Land management; Land use; and Fauna species. GIS was used to assess and score each 1-km grid cell in relation to each of these criteria. Each grid cell was then assigned a final score, based on the addition of scores from each of the five criteria, to give a final priority rating. This is shown in Figure 6. An explanation of each of the criteria, the measures and limitations are given in Table 2. Details of the methodology, including the scoring system and GIS layers used are given in Appendix 3, with mapping in Figure 8. Final 21

27 Table 2 Site prioritisation criteria for fox control in the Western Port Biosphere Reserve Criteria Rationale Measure Limitations Spatial coverage Spatial coverage of control areas is one of the most important factors influencing the efficacy of a control program. Undertaking fox control adjacent to areas already subject to fox control efforts, will expand the area of control, and will be more valuable than undertaking control in an isolated area. Each grid cell was assigned a score on the basis of location in relation to current control areas: Cells adjacent to current control areas = 1 Cells not adjacent to current control areas = 0 Data on current control works was provided as either a point location or polygon, around which the potential area of influence was estimated. These areas were not included in the analysis. In some areas (e.g. polygons) the current area under management may have been overestimated. Extent of remnant vegetation Native vegetation is greatly depleted across the WPBR. Thus, remnant vegetation in this landscape is of high conservation value. It provides habitat for a range of fauna species and contributes to ecosystem function. Areas supporting large patches of remnant vegetation are also likely to be more amenable for the implementation of control activities, particularly baiting. The area of remnant vegetation within each grid cell, in hectares, was calculated using EVC mapping. The total area for each cell was then given a standardised score, between 0 and 1. The mapping of remnant vegetation (EVCs) is based on modelling undertaken by DEPI, and may not always reflect on-ground native vegetation cover. Land Management Land management objectives influence the suitability of a site for fox control. Areas managed with a conservation objective will be more amenable to fox control than other areas, where management priorities may be incompatible with fox control. These primarily includes areas of public land, both reserved and unreserved, and should be targeted first. Public land management layers were used to identify sites managed by public land management authorities, as an indicator of suitability for fox control. The area of each cell covered by a public land management authority was calculated in hectares and assigned a score: 50% = % = 0.75 The Public land management layer was used to identify sites which may be managed for conservation objectives. The layer identifies land managed by agencies such as Parks, DEPI and Council, and includes parks and reserves. However, other areas of public land, where baiting may not be feasible, may have also been included, such as public recreation reserves % = 0.5 <10% and adjoining a cells with 10% public land = 0.25 <10% and not adjoining a cell with 10% public land = 0 Final 22

28 Criteria Rationale Measure Limitations Land Use Land use, particularly the level of urban development has an influence of the type of control works which can be undertaken within an area. Urban development limits the range of techniques which can be used. Baiting is generally not possible in high density urban areas. Therefore, baiting must necessarily be targeted to public reserves and rural land uses. Planning Schemes control the land use and level of urban development within each zone. Planning Scheme zones were used to reflect land use. Each cell was assigned a score based on the dominant land use zone for that grid. Public or Commonwealth Land zones = 1 Private land - rural or semi-rural land use zones = 0.5 Areas zoned for public use provide for a variety of uses, including conservation reserves, roads and railways, waterways, and schools. Therefore, not all areas zoned for public use may be suitable for fox control. Controls on land use within particular zones may also vary between municipalities. Private land urban zones = 0 Fauna Species The WPBR supports a number of significant fauna species, many of which are vulnerable to fox predation. One of the main objectives of the predator control program, under the Growing Connections project is to enhance biodiversity values within the WPBR. A score for each grid cell was calculated from the number of fauna species that are considered vulnerable to predation. The total number of fauna species was then divided by the highest value to give a standardised score between 0 and 1. Fauna records are based on site survey data which has been submitted to the DEPI. The data set is not complete and some sites have been surveyed more than others. A lack of records may reflect a lack of survey effort, and not necessarily the absence of significant fauna species. Final 23

29 Growing Connections Biodiversity Significance Mapping As part of the Western Port Biosphere Reserve Biodiversity Plan (WPBRF 2015), the WPBR Foundation produced biodiversity significance mapping, to prioritise areas across the WPBR, from very low to very high, for the Growing Connections Project. The significance mapping was based on known biodiversity values, GIS land-use datasets and expert and local knowledge; a full description of the methodology and the mapping is provided in WPBRF (2015). The biodiversity significance mapping produced as part of the Biodiversity Plan displays a number similarities, in the prioritisation of sites, to the mapping produced as part of this strategy. This is partly due to the use of similar datasets with regard to significant biodiversity values within the WPBR. However, the mapping produced as part of this project has a greater focus on areas where greater benefit may be achieved for predator control, due to the spatial arrangement and feasibility of predator control. Areas of land prioritised as Medium, High and Very High in the Biodiversity Plan were overlaid on the predator control site prioritisation mapping, to highlight any additional areas of importance and to align with other works undertaken as part of the Growing Connections Program. Predator Control Prioritisation Mapping The predator control prioritisation mapping is shown in Figure 3, below. The Mapping shows priority areas identified as part of this strategy (i.e. coloured grids ranging from cream to dark-blue, with the highest priority being dark-blue) and priority areas identified by the WPBR Foundation, as part of the Biodiversity Plan (i.e. orange, blue and green-hatched grids). The map shows that some areas identified by the WPBR Foundation correspond to those areas identified as high priority by this strategy, as well as additional areas. It should be noted that areas around the Western Port Coastline which have been given the lowest priority rating by this strategy (i.e. cream grids), have been assigned this rating only because predator control works are currently being undertaken in these areas, and the aim of the mapping was to identify additional areas. Hence, if funding for these programs is withdrawn in future, then re-instatement of works in these areas should be the first priority, over the other areas identified here. These areas have also been identified as being of high significance by the WPBR Foundation. This mapping is intended to guide future control works by various agencies, across the WPBR, as part of the Western Port Pest Animal Group, which is expected to have a life beyond the Growing Connections Program. As part of the Growing Connections Program, this mapping also provides further guidance to the WPBR Foundation, on target control areas, in order to achieve the 125 ha target. The following geographic areas have been identified, in order of priority, for the WPBR Foundation to focus on, and undertake further investigation, specifically as part of the Growing Connections Project: 1. The area around Tooradin, between Blind Bight and The Inlets, to fill the spatial gap in predator control works currently undertaken along the Western Port Coastline; 2. The area around Cardinia and Toomuc Creeks, north of the Inlets, which broadly connects this area with the Coast, (i.e. The Inlets, through Tooradin to Hastings); 3. The area south of Crib Point, to complete the connection around the coast. Final

30 Figure 3 Site prioritisation analysis for future control works, showing areas of varying priority within the Western Port Biosphere Reserve (combined with significance mapping from the WPBR Foundation) Final 25

31 5 Control Techniques Determining the most appropriate techniques depends on the purpose and scale of control, and must balance the efficacy of various techniques with associated costs, risks and feasibility of implementation in particular areas. This section outlines the range of control techniques recommended for the WPBR to reduce the impacts of foxes and rabbits, with management options for cats, as part of an integrated control program. The selection of techniques is based on an assessment of the benefits, limitations, costs and feasibility of each control technique, as shown in Appendix 1. Protocols are provided for the on-ground delivery of each technique, based on best-practice and state regulations, to facilitate integration across programs. 5.1 Foxes Poison Baiting Poison baiting is considered to be the single-most effective fox control technique and is widely used throughout Australia with high rates of success (Saunders and McLeod 2007). In Australia, poison baiting has been used in both broad-scale, cross-tenure fox control programs co-ordinated by government agencies, as well as by individual landholders, as part of smaller neighbourhood control programs. However, the success of this technique depends on the scale, frequency, timing and method of bait deployment, as well as bait placement (see below). It is most effective when employed as part of a co-ordinated, landscape-scale program; implemented in this way, poison baiting is capable of economically achieving substantial reductions in fox populations, over large areas. In, poison baiting is generally undertaken using fresh or commercially produced meatbased baits, impregnated with 1080 (sodium monofluoroacetate), which are buried in the ground (Figure 3). The 1080 toxin is currently the most widely used as it is economical, readily biodegradable, and is highly toxic to canid and felid species, which are relatively more susceptible than native species. With good baiting practices, the risks of 1080 to non-target species are relatively low. In eastern Australia, burying baits is a standard practice employed to safeguard non-target species by reducing their access to toxic baits (Dexter and Meek 1998, Glen and Dickman 2003, Staples and McPhee 1995). Used properly, 1080 remains the most suitable toxin currently available for broad-scale fox control. However, other toxicants and delivery methods are currently being developed. These include para-aminopropiophenone (PAPP) and M-44 ejectors. PAPP PAPP is currently being assessed for registration by the Australian Pesticides and Veterinary Medicines Authority (APVMA). While not yet commercially available, the use of PAPP when available, has several advantages over 1080, including: the availability of an antidote, which is effective if delivered within 20 minutes of poisoning; reduced non-target impacts for many native species (Fleming et al. 2006); and improved welfare outcomes for foxes due to a more rapid death and the appearance of fewer distress symptoms prior to death (Marks et al. 2004). However, early trials have indicated that bandicoots may have an even higher sensitivity to PAPP than foxes. Coupled with their low body weight, this means that PAPP may be highly lethal to bandicoots which are a significant biodiversity value in the WPBR. Final 26

32 Risks to bandicoots would depend on the accessibility of baits and their palatability. The overall risks to bandicoots have not been properly assessed. Until then, PAPP is not recommended unless other delivery mechanisms can also be used (i.e. M-44 ejectors). M-44 Ejectors M-44 ejectors are spring-loaded devices which are partially buried in the ground and loaded with an attractant (Figure 4). When pulled, the mechanism propels the toxicant into the animal s mouth. These devices have the potential to increase the efficacy of a baiting program. When triggered, the ejectors effectively and reliably deliver a lethal dose of 1080, which has been protected from degradation due to water leaching, and insect and microbial activity, allowing a lower dose of 1080 to be used. This reduces the risk of sub-lethal dosing and bait caching. Multi-shot ejectors are being researched and developed which would also offer the advantage of multiple fox kills per deployment. M-44 ejectors are also designed to significantly increase the target-specificity of poison baiting; the device can only be triggered by an upwards pulling motion and can be set to be activated only at a specific pull-force. This means that commercial deployment of ejectors may allow for long-term, target specific fox control with minimal on-going labour requirements. Bait Selection and Deployment A large number of different bait types and attractants have been trialled for fox control across Australia, including commercially prepared baits (Saunders and Harris 2000). However, there is no clear evidence on bait preferences, and it is generally considered that foxes will consume most bait types. Meat-based baits are commonly used because of their high palatability and target-specificity (Saunders and McLeod 2007). Commercially manufactured dried meat 1080 baits (e.g. FoxOff ) are recommended for use within the WPBR, because of their longevity (compared to fresh meat baits), unless the uptake of baits is considered to be too low. In this case, fresh or dried meat baits could be trialled. The use of Synthetic Fermented Egg products (SFEs), which are highly attractive to foxes, has been found to significantly increase visitation of bait stations by foxes (Saunders and Harris 2000, Saunders and McLeod 2007). Therefore, SFE s (e.g. FeralMone ) are also recommended for use within the WPBR, to help maximise bait up-take. All poison baits deployed within the WPBR, should be laid in accordance with n guidelines, which specify burial to a depth of 15 cm, within a soil mound, to reduce non-target risks, as shown in Figure 3. As PAPP and M-44 ejectors become available, these should be trialled within the WPBR, to assess the benefits and risks, and determine whether they are suitable for use in the region. In particular, trials should assess the potential risks to Southern Brown Bandicoots and domestic dogs. Baiting Density The density of baits required to achieve an effective reduction in the fox population is a function of the density of foxes in a given area, and home-range size. Ideally, the baiting density should provide each fox with the chance of encountering poison bait; baiting densities that are too low will result in low encounter rates, and low mortality. However, the home range-size and density of foxes, across different land types in the WPBR, is not known; Final 27

33 research on the home range and movement patterns of foxes in urban areas of the Mornington Peninsula is currently being undertaken, and may provide some direction in future. A number of other factors, including land tenure, distance to human habitation, and non-target risks must also be considered. Based on density estimates from central (Coman et al. 1991), it is anticipated that the predominantly agricultural landscape within the WPBR, supports approximately 4 foxes km -2, although, higher densities may occur around townships or industrial areas. To achieve a 75% reduction of the fox population, three in four foxes must be killed. On this basis, a baiting density of 9-12 baits km -2 would be required (providing approximately 3 baits per fox); a density of 12 baits km -2 has also been used in rural NSW to achieve an estimated 70% reduction in the fox population, where fox density was estimated between 4 and 7 foxes km -2 (Thomson and Fleming 1994). A baiting density this high may not be achievable in the WPBR for various reasons, such as levels of landholder participation, funding or resource availability, or risks to domestic animals. However, based on results of other baiting programs around Australia, a baiting density of at least 5 baits km -2 is generally required in order for baiting to be effective in agricultural landscapes (see Saunders and McLeod 2007). Thus, baiting densities in the WPBR should be as high as feasible, determined on a case-by-case basis. Bait Distribution and Placement The spatial distribution of baits is important for maximising the efficiency of the baiting program. An even distribution is likely to provide more foxes with the chance of encountering baits and therefore, reduce the re-colonisation rate. Leaving gaps in the landscape can entirely miss some fox territories, which can act as a source of immigration into baited areas (Carter et al. 2011). The spatial coverage of bait stations across the landscape will depend on the level of landholder participation (among other factors); an effective landholder engagement program is therefore, an essential part of this program (see Section 7.2). Strategic direction on areas to target as part of a baiting program is outlined in Section 5. Within baited areas, the targeted placement of baits can increase the likelihood of foxes encountering baits, and affect the rate of bait uptake (Carter et al. 2011, Carter and Luck 2013). Where possible, baits should be deployed near roads and vegetated creek corridors. The placement of baits near these landscape features has been shown to result in higher rates of bait uptake than along fence-lines or in open paddocks (Carter et al. 2011, Carter and Luck 2013). Placement of baits within a particular property should be determined on-ground and with the aid of GIS and aerial photography, with bait stations mapped on GIS for future analysis (see Section 7.3); distance restrictions must also be adhered to, as per DEPI (2014). Timing, Frequency and Duration The timing, frequency and duration of poison baiting can determine the success, or otherwise, of a fox control program. Fox control undertaken for the protection of native wildlife, typically requires a sustained an on-going effort to maintain fox populations at low densities year-round. Short-term baiting programs have been shown to be ineffective in producing long-term reductions in the fox population, as the temporary reductions achieved during baiting, are quickly compensated for by immigration, breeding or increased survivorship in the remaining population (Saunders and McLeod 2007). Final 28

34 Broad-scale fox control programs which have been successful in recovering native wildlife typically employ a continuous baiting regime, or a pulsed regime, where baits are deployed in long pulses throughout the year. The efficacy of these regimes has been demonstrated with an adaptive experimental fox program trialled at a number of sites across (Robley et al. 2008). A continuous baiting regime is likely to provide maximum benefits for biodiversity and will enable patterns or annual cycles in predator and prey abundance across the landscape to be elucidated. However, a pulsed regime may receive greater acceptance from the local community, and encourage greater participation. Wherever poison baiting is undertaken within the region, an action plan for reducing the risks to domestic animals should be developed and implemented. Recommendations for this are provided below. Protocol: Poison Baiting (1080) Materials 1080 Baits: - Manufactured FoxOff baits, containing 3.5g Where bait palatability is low and potentially affecting bait uptake, the use of novel baits, such as dried liver or chicken may be required Synthetic fermented egg attractants (e.g. FeralMone TM ). GPS Sand of local provenance Shovel, rake Data recording sheet (e.g. see Appendix 2) Procedure Bait Density The maximum allowable density of fox-baits is 12.5 / km 2 ; given the likely densities of foxes in the study area (c. 4-8 / km 2 ), baiting densities in the study area should be at least 5 and where possible up to 12 / km 2. Baiting density will most likely depend on the level of participation. Bait Placement Placement of baits within the landscape is best determined from GIS and onground inspections to select sites which may maximise bait uptake; Avoid placing bait stations in low-lying or frequently inundated areas; and Where possible, consider placing baits near roadsides and creek lines. Bait Deployment All 1080 baits are to be buried in bait stations. Bait stations will consist of a hole dug to c. 15 cm deep into which the bait is placed and covered with the loose soil (rocks and vegetation removed); sand/fine soil is then placed in an area of c. 1 m 2 of the bait to around 10 cm deep (i.e. a mound ), resulting in a depth to the bait of 15 cm or greater (see Figure 3); FeralMone TM should be used at all bait locations (i.e. a small amount placed adjacent to, not on, the bait); and Mark and record the location of each bait station with a GPS, to be mapped on GIS. Final 29

35 Free-feeding An initial free-feeding period is recommended for monitoring purposes, to assess the risks of non-target bait-take, at the commencement of the program; Deploy non-toxic baits within constructed bait stations, as detailed above; Monitor the bait-stations daily, and replace baits as necessary, to maintain the same number of baits in the landscape each day; Record frequency of bait-take; and After the rate of bait-take has reached a plateau, replace all non-toxic baits with toxic baits. Continue with poison baiting thereafter. Bait Checking and Replacement Baits should be checked fortnightly; Replace baits if they have been taken or disturbed, or after significant rainfall (>25 mm); Replace baits if they have not been taken after one month, and there has been no heavy rainfall; and Record each bait-check and replacement consistently. Data Collection Date of commencement; Site and Bait station Identifier; Location (GPS coordinates); Bait type (Free-feed or poison); Date of bait laid, checked and replaced; Fate of bait (e.g. taken, not taken, exposed, degraded); Indicators of fox presence or presence of other species; Time taken to complete operation; and Number and names of personnel. Regulations All relevant legislation and regulations must be followed when using 1080 baits, including warning signage and notification of neighbours, and distance restrictions (see DEPI 2014). Figure 4 Bait station design for buried 1080 poison baits (redrawn from Murray et al. 2006) Final 30

36 Protocol: Poison Baiting (M-44 Ejectors and PAPP) Materials Bait capsule containing 2.7mg PAPP; Procedure M-44 Ejectors (see Figure 4) ; GPS; Shovel; Personal protective clothing and First Aid kits; and Data recording sheet. Bait Density Densities of M-44 ejectors should be the same as 1080 baiting. Bait Deployment M-44 ejectors, with a PAPP toxicant, should be implemented once PAPP is registered and commercially available, firstly as part of a trial; and Mark and record the location of each bait station with GPS, to be later mapped on GIS. Bait Checking and Replacement Ejectors deployed in the field should be checked/maintained every month at a minimum; more frequent checking (e.g. weekly) will reduce the time that ejectors are triggered (i.e. inactive) and will increase both the effectiveness and accuracy of estimates of fox activity/kills; Maintenance checks allow baits to be refreshed, and also provide an opportunity to change the type of bait heads regularly (e.g. liver, kangaroo, lamb, etc.); and Synthetic fermented egg attractants (e.g. FeralMoneTM) should be used at all bait locations (i.e. a small amount placed adjacent (not on) the bait). Data Collection As for poison baiting with Regulations All relevant legislation and regulations must be followed when using PAPP baits, including warning signage, notification of neighbours and distance restrictions; and Relevant regulations and OH&S precautions must be followed when working with toxicants. PAPP regulations are yet to be developed. Final 31

37 Figure 5 Diagrammatic representation of an M-44 ejector (taken from Ecology Australia 2013) Action Plan: Reducing risks to domestic animals Provide free dog-muzzles to all landholders in fox control areas, who have dogs that may be at risk of poisoning; Distribute First Aid kits for dogs, which includes a booklet, packet of salts and instructions on administration; Notify local veterinarians about the nature and locations of baiting programs; Hold a workshop or information session for local veterinarians to address animal welfare concerns for domestic animals, and pest animals. The session should explain the objectives of the program and the legalities of 1080 baiting; Invest in raising community awareness through extension programs (additional to letters and signage); and Undertake toxicology for any domestic animals suspected of 1080 poisoning. Final 32

38 5.1.2 Den Fumigation Fumigation of natal fox dens, using carbon monoxide gas (CO), provides one of the most humane and target-specific forms of fox control currently available (Sharp and Saunders 2004). Den fumigation is undertaken during the fox breeding season, using combustible cartridges, or a fumigator to pump CO into the den; it causes death to foxes by depriving the brain of oxygen, rendering them unconscious before death. Den fumigation mostly causes mortality in cubs; the vixen only remains in the den for the first few weeks following birth, and the male rarely inhabits the birth den. Thus, den fumigation does not necessarily remove resident foxes. However, it removes the next generation of foxes, which has been shown to contribute most to the rate of population increase (McLeod and Saunders 2001). Den fumigation is generally not considered suitable for broad-scale application due to the difficulty of locating active natal dens, which are often widely dispersed. However, it can be effective when used in conjunction with poison baiting, as part of an integrated strategy, particularly if dens are not destroyed following fumigation. Destroying dens by ripping with machinery after fumigation can reduce the availability of den sites, which is known to influence the density of fox populations (Marks and Bloomfield 2006). However, this simply forces foxes to den within more marginal habitat, or selects for foxes which excavate dens in areas that are more difficult to manage. Leaving dens intact provides an opportunity to map, monitor and undertake systematic and repeated control of foxes each year. The success of this technique is due to the high fidelity foxes show to natal dens between years. The large effort required to locate dens can be overcome by engaging the community in a program to locate and record dens on their property, which can then be entered into a central GIS-enabled database. Mapping of fox dens not only allows for systematic survey of the dens during the breeding season, but also allows fox numbers to be monitored based on the number of active natal dens. It can also help to target fox control efforts; for example, baiting during August and November could be targeted to areas around natal dens, where baits are likely to be taken back to dens by the male or vixen, targeting both adults and cubs. Final 33

39 Protocol: Den Fumigation Materials DEN-CO-FUME cartridges or portable fumigator; GPS; Shovel; Fibre cement sheets; Protective clothing and First Aid kits; and Data recording sheets. Timing During the breeding season, while cubs are still confined to the den: Ideally, August to October to target dens with cubs greater than 4 weeks old. Procedure Prior to fumigation, the den should be checked for evidence of den use by native fauna (e.g. bandicoots, wombats, snakes); fumigation should never be undertaken unless their absence can be established; Fumigation should be used in natal dens that have signs of current fox activity, such as cub footprints, flattened vegetation or a distinctive fox odour; Do not use sand-pads outside den entrances to confirm fox presence; this can cause vixens to relocate the cubs (Carter 2011); Once activity is confirmed, locate all den entrances, and cover and secure each entrance with a 1m 2 piece of fibre cement sheeting, and cover with soil to prevent the gas escaping, leaving one entrance open; Combustible cartridges can be used in most circumstances, but where access to den sites is problematic, or where cartridges pose a fire risk, a fumigator should be used; At the last open entrance, insert the cartridge or pipe of the fumigator, and then seal. More than one cartridge may be required for dens with multiple entrances; After combustion, wait 10 minutes before removing fumigator pipes, and reseal dens; Leave dens sealed for 24hrs; Data Collection Date and time; Do not destroy dens following fumigation. This does not remove foxes, but encourages them to den elsewhere when suitable areas are destroyed; and Record the location of each den with a GPS to be mapped on GIS for monitoring purposes. Names of personnel; Den location and GPS co-ordinates; Signs of fox activity; Non-target species use; and Number of den entrances. Regulations Relevant regulations and OH&S precautions must be followed when working with fumigants; Avoid use during hot, dry and windy conditions; Follow the Material Safety Data Sheet (MSDS); and Prevention of Cruelty to Animals Act 1986 and Prevention of Cruelty to Animals Regulations Final 34

40 5.1.3 Trapping Trapping of foxes is undertaken with soft-jaw (i.e. rubber) leg-hold or foot-hold traps; cage traps are generally considered to be ineffective (Saunders and McLeod 2007). A variety of humane soft-jaw trap models have been developed and tested world-wide. These include traps with padding and offset jaws, foot snares, treadle snares, and pan-tension modifications, which reduce the risk of injury to the captured animal and the number of non-target captures. Traps are often deployed with scent lures and set along access tracks, animal tracks or in areas where there are signs of fox activity. Trapping is frequently used in areas where lethal methods are not permitted or considered a high risk to non-target species, such as near areas of urban development. However, trapping is labour-intensive and costly, and trapping success is generally low (Meek et al. 1995, Kay et al. 2000, van Polanen Petel 2004). As such, trapping is not suitable for broad-scale fox control. Trapping within the WPBR should be used as a supplementary technique only, at locations where poison baiting is not permitted by the landowner, or considered to be an unacceptable risk to domestic animals. Trapping can be undertaken throughout the year, except for August- September, when vixens are likely to be lactating, for animal welfare reasons. Protocol: Soft-jaw Trapping Materials Victor Soft-Catch Soft-jaw Trap (#1 1/2 or #3), with a jaw spread of between 11 and 14 cm; Meat bait (beef heart, lamb, chicken or rabbit); Synthetic fermented egg attractants (e.g. FeralMoneTM); GPS; Data recording sheets; and Small calibre firearm (for euthanasia). Procedure Trap location Traps should be set in areas where the problem foxes or dogs are believed to frequent, such as on tracks and trails, ideally in shade; Avoid setting traps adjacent to objects that the captured animal may get tangled in, such as fences and vegetation; and Avoid areas known to be frequented by non-target animals. Trap setting and checking Prepare a hole in the ground, secure the trap, then set and cover with a fine layer of soil and leaf litter cm in diameter over the trip plate; Place the bait behind the trap, at a distance where the animal is likely to step on the trap while investigating the bait; Place a small amount of attractant, adjacent to, but not on the bait; Record the location of all traps with GPS, to be later mapped on GIS; Traps should be set at the end of the day and checked early each morning (4-8 h later), so as to minimise time an animal is held in the trap; If traps are to be set during the day, they should be checked in the afternoon; Captured animals should be approached quietly to reduce panic; Final 35

41 Any non-target animals caught should be inspected for injuries and released at the point of capture if considered unharmed, or suffering from minimal injuries; and Non-target animals suffering from severe injuries should receive appropriate veterinary attention. Fox/Dog disposal Data Collection Trap number; Captured dogs should be assessed to determine if they are domestic or wild. Domestic dogs should be transferred to Council if safe to do so; Captured foxes or wild dogs are to be euthanased while held in the trap with a gunshot to the head, by a licensed and experienced operator; and Death should be verified by corneal reflex before disposing of animals by incineration or burial in a 1m disposal pit. Trap location and co-ordinates; Names of personnel; Date of commencement, each trap check and completion; Duration of operation; Number of foxes trapped; Sex and age-class of each fox trapped; Overall body condition of foxes trapped; and Non-target species trapped. Regulations All relevant legislation and regulations must be followed when trapping foxes and dogs, including legislation regarding animal welfare (e.g. Prevention of Cruelty to Animals Act 1986, and Prevention of Cruelty to Animals Regulations 2008); and Notify the public prior to trapping to enable residents to take necessary precautions for pets. 5.2 Rabbits Poison Baiting Poison baiting can quickly and effectively reduce rabbit populations; implemented correctly, baiting can remove up to 90% of the rabbit population, and when undertaken in conjunction with warren destruction, achieves long-lasting control (DEWHA 2008c). Baiting is most effective during late-summer and early-autumn, when disease and natural causes are likely to have reduced rabbit numbers to base levels. During this time, feed is typically limited, and rabbits are also likely to increase foraging and range over greater distances. Baiting at this time also reduces rabbit numbers before the peak breeding season (Bloomfield 1999c). Two toxins are currently registered for rabbit control in : 1080 and Pindone (Bloomfield 1999c). Pindone is often the preferred toxin (particularly near urban areas), because of the availability of an antidote (Vitamin K1), and is the toxin used in commercially produced rabbit baits. However, Pindone has been known to cause mortality in bandicoots in Final 36

42 Western Australia (Twigg et al. 1999), and is therefore, not recommended for use in the WPBR, which supports an important population of Southern Brown Bandicoots. Rabbit baiting using 1080 involves laying trails of 1080-laced diced carrots, pellets or oats near warrens or feeding areas. Rabbit baiting with 1080 has not been shown to have a negative impact on populations of native species, although there have been some cases of individual deaths, where large amounts have been consumed (Brunner 1983, McIlroy and Gifford 1991). Risks to native wildlife depend on the palatability of the bait and the amount consumed. Oat baits are not readily consumed by most species, and can be dyed green or blue to further reduce their attractiveness. Other measures, such as using surface coated rather than impregnated oats, will help reduce risks to granivorous birds, which typically discard the husks (Sharp and Saunders 2004). To reduce the risk of secondary poisoning to domestic animals, efforts should be made to remove rabbit carcasses after poisoning campaigns. Protocol: Poison Baiting (1080) Materials 1080 Baits: - Surface coated, blue or green-dyed oats to reduce exposure to nontarget species - Pindone must not be used due to potential impacts on Southern Brown Bandicoots; Personal protective clothing and First Aid kits; GPS; and Shovel. Timing Late-summer to early-autumn, when the ground surface is dry, and there is a low chance of rain within the following days; Before warren ripping or fumigation; and The principle for rabbit baiting should be to conduct it as infrequently as required, with a maximum kill-rate (to minimise bait-shy rabbits and maximise benefit). Procedure Bait Placement Baits should be laid along areas of rabbit feeding activity and marked; and Baits can be placed under a mesh canopy to reduce access to non-target species if they are considered to be at risk, including livestock. Bait Deployment Free-feed with non-toxic baits, 2-3 times, approximately 4 days apart; Lay baits in a pre-cut furrow, where pasture is short or absent; Laying baits in the evening can reduce exposure to diurnal native species, including birds and some herbivores, and may increase consumption by rabbits, which feed at night; Baits should be replaced according to the average period until sub-lethal dose is reached under prevailing conditions; usually 2-3 days; and Uneaten baits should be buried or removed and destroyed at the conclusion of the baiting period; carcasses are to be removed approx. 14 days following baiting where possible. Final 37

43 Rabbit disposal Rabbit carcasses should be disposed of by incineration or burying in a pit, to a minimum depth of 50 cm; and Disposal pits should not be located near waterways. Data Collection Date of commencement; Bait trail location; Bait type; Date of bait laid, checked and replaced; Fate of bait (e.g. taken, not taken, exposed, degraded); Time taken to complete operation; and Number and names of personnel. Regulations All relevant legislation and regulations must be followed when using 1080 baits, including warning signage, notification of neighbours and distance restrictions Warren Destruction and Fumigation Rabbit control programs which do not include the destruction and fumigation of rabbit warrens are ineffective. This is because warrens (and above-ground harbours) are a critical resource for the European Rabbit, which increase survival. Warren destruction, either by hand, or with machinery or explosives, is an important follow-up control technique to poison baiting, used to prevent the recolonisation of an area by rabbits. The most efficient means of destroying rabbit warrens, on a larger scale, typically includes machinery, such as bulldozers, excavators, backhoes or tractor-mounted tynes; the most appropriate machinery to use will be determined by the terrain. Explosives may be useful in particular circumstances, where ripping is not possible, or for those areas which are repeatedly recolonised (Bloomfield 1999c). At locations where poison baiting cannot be undertaken, or for areas that are inaccessible to ripping machinery, warren fumigation may be more appropriate, although it is typically more expensive and labour intensive. Fumigation of rabbit warrens is undertaken by depositing gasgenerating tablets within the warren (i.e. diffusion fumigation) or by pumping a toxic gas mixture through the warren with a machine (i.e. pressure fumigation). Two fumigants are currently registered for use in aluminium phosphide and chloropicrin. Chloropicrin is generally not considered to be as humane as aluminium phosphide as it can cause significant irritation of the respiratory tract prior to death (Sharp and Saunders 2004), and is not permitted for use within the DELWP. Final 38

44 Protocol: Warren Ripping Materials Bulldozer, excavator, backhoe or tractor mounted ripper; Blade plough for sandy soils; GPS; Personal protective clothing and First Aid kits; and Data recording sheets. Timing Best undertaken before the rabbit breeding season, after poison baiting, when the density of rabbits is likely to be lowest. Procedure Warrens should be checked for native fauna prior to destruction. Where there is evidence of warren use by native fauna (e.g. bandicoots, wombats or snakes), ripping or fumigation must not be undertaken unless their absence can be established; Appropriate consideration of potential impacts to native vegetation must be undertaken prior to ripping commencing; where impacts are likely to be significant, alternate methods targeting warrens should be used (i.e. fumigation or explosion); Prior to ripping, fumigation and explosion, flush rabbits into warrens using loud noises or dogs; Record the location of each warren with a GPS to later be mapped on GIS; Locate burrow entrances; Data Collection Date and Time; Seal all burrows and rip the warren to at least 0.5 m, and preferably to 0.9 m (may need to be deeper in sandy soils); Ripping should extend at least 2-3 m beyond the visible extent of the warren (see Figure 5); Rip along contour lines (not against); cross-ripping may be required in some areas (e.g. Figure 5); Avoid ripping during or immediately following high rainfall; lighter soils should be ripped when dry, while heavier or clay soils should be ripped when damp; When ripping on slopes, ensure final rip lines run cross-slope to reduce erosion; Check the ripped areas 1 week later for signs of re-use and rip again or fumigate if required; In conservation areas, re-seed ripped areas with fast-growing indigenous species; and Removal of surface harbour may be required either in areas to be ripped, or in areas where ripping is not feasible; and potential impacts to native fauna must be considered. Names of personnel; Warren location and GPS co-ordinates; Signs of use by non-target species; Number of burrow entrances; Diagram of warren; and Date of warren check (1 week later) for re-invasion. Regulations Experienced operators with appropriate licences are required for warren- Final 39

45 ripping, fumigation and explosion; and Follow the Material Safety Data Sheet (MSDS). Figure 6 Diagrammatic representation of rabbit warren ripping (taken from Ecology Australia 2013) Protocol: Warren Fumigation Materials Tablets or pressure fumigator; GPS; Shovel; Personal protective clothing and First Aid kits; and Data recording sheets. Timing Best undertaken before the rabbit breeding season, after poison baiting, when the density of rabbits is likely to be lowest. Procedure Warrens should be checked for native fauna prior to fumigation. Where there is evidence of warren use by native fauna (e.g. bandicoots, wombats or snakes), fumigation must not be undertaken unless their absence can be established; Prior to fumigation, flush rabbits into warrens using loud noises or dogs; Record the location of each warren with a GPS to later be mapped on GIS; Locate burrow entrance; Use a gas tablet or pressure fumigator depending on availability; Final 40