The management documents relevant to the Shark Bay region and to the management and translocation of threatened Shark Bay marsupials include:
Barrow Island Nature Reserve Interim Management Guidelines (CALM 1999a)
Environmental Impact Statement/Environmental Review and Management Programme for the Proposed Gorgon Development (Chevron Australia 2006)
Dryandra Woodland Management Plan 1995 – 2005 (Friend et al. 1995)
Faure Island Pastoral Lease Management Plan (Australian Wildlife Conservancy 2002b)
Heirisson Prong Community Biosphere Reserve Management Plan 1999 – 2004 (Short 1999b)
Project Eden Draft Strategic Plan 2006
Shark Bay Terrestrial Reserves Management Plan 2000 – 2009 (Hancock et al. 2000)
The Action Plan for Australian Marsupials and Monotremes (Maxwell et al. 1996)
Western Shield Fauna Recovery Program Draft Interim Strategic Plan 2009-2010 (DEC, 2008)
Western Shield – Bringing Back our Wildlife (Burbidge et al. 1995)
A DEC draft management plan for Barrow Group Nature Reserves and two new departmental final management plans for Shark Bay Terrestrial Reserves and Proposed Reserve Additions and Dryandra Woodland are currently in preparation and will be relevant to this recovery plan once they are formally released.
Management of re-introduction sites
At Heirisson Prong the local community maintains a 2.8 km predator-proof barrier fence, conducts regular ground baiting for fox control, liaises with DEC regarding the organisation of an annual aerial baiting for foxes and cats, and conducts trapping for feral cats in the area surrounding the conservation site. The continuity of this management, particularly predator control, is important for the long-term security of the threatened mammal populations.
The Uluru-Kata Tjuta National Park enclosure is surrounded by a four-metre firebreak free of vegetation, and the external perimeter is burnt at a distance of up to 100 m from the fence line to minimise fire risk. The enclosure is maintained fox, cat and dingo-free.
At Barrow Island petroleum exploration and production activities began in the mid-1960s, and through cooperative environmental management practices developed initially by West Australian Petroleum Limited and more recently by Chevron, and DEC, the conservation values of the island have remained protected. The current Gorgon Joint Venturers have adopted a risk-based approach to Quarantine Management on Barrow Island due to an increased risk of introduction of exotic species through the proposed Gorgon development (Chevron Australia 2005). This environmental management plan complements the Barrow Island Nature Reserve Interim Management Guidelines (CALM 1999a), with the aim of continuing to protect the population of burrowing bettongs, and the integrity of other native fauna and flora and their island habitat. Chevron has committed significant funds to cover environmental management issues on Barrow Island including fauna monitoring and surveillance for early detection of biosecurity incursions and a fauna education program for the workforce on the island.
Lorna Glen has been destocked and artificial watering points closed since 2000. In 2003 an annual aerial baiting program was commenced to control foxes and feral cats. Aerial baiting and strategic trapping at Lorna Glen has maintained feral cat activity at approximately 7-11 cats per 100km, a reduction of approximately 75% over pre control levels. Whilst foxes are rarely detected wild dogs are present and controlled to some extent by the cat baiting program.
Recovery team and recovery planning
A recovery team for the western barred bandicoot, burrowing bettong and banded hare-wallaby was established in late 2004 by CALM (now DEC), to coordinate conservation actions for these species. The inaugural meeting was held in February 2005 and the recovery team continue to meet annually. Much of the information contained within this recovery plan has been collated through past recovery actions, the Report on Threatened Shark Bay Marsupials (Richards 2003), recovery team meetings and the assistance of numerous people involved in the conservation of Australia’s threatened mammals.
Management of wild populations
DEC is responsible for the management of Bernier, Dorre, Barrow and Boodie Islands and their resident populations of threatened mammals. The Bernier and Dorre Islands Nature Reserve is not promoted for recreational use, and while day access is allowed, overnight camping is prohibited. The Nature Reserve is designated a 'No Planned Burn Area', and management strategies prohibit all open/wood fires. There is provision for facilitating early detection of fire through local community (predominantly fishermen) and agency communication. In the event of a fire, immediate monitoring will be undertaken to assess whether suppression is warranted or feasible.
Although fires are infrequent within the Shark Bay region, fire management continues to minimise the risk of fire, both on Bernier and Dorre Island, and at reintroduction sites within that region (François Peron NP, Heirisson Prong and Faure Island). Where the potential of fire is more likely, such as Lorna Glen and Scotia Wildlife Sanctuary, there are fire management regimes implemented by DEC and AWC and DEC operates the incident management system for incident response.
Monitoring of wild populations
Long-term monitoring of the western barred bandicoot and burrowing bettong populations on Dorre Island was typically carried out on an annual basis (and sometimes more frequently) using established trapping grids at White Beach on Dorre Island by CALM (now DEC) from 1986 to 1988, and 1992 to 2000 (Richards 2003). CSIRO conducted comprehensive spotlighting and trapping surveys of Bernier, Dorre and Barrow Islands in 1988 and 1989, and repeated these three years later at Bernier and Dorre Islands (Short et al. 1998; Short and Turner 1999). The only systematic monitoring of banded hare-wallabies has been by CSIRO. Other monitoring of the banded hare-wallaby populations has typically been sporadic and ad hoc, conducted opportunistically by hand netting, and was detailed in Richards et al. (2001).
Regular monitoring of the Barrow Island Nature Reserve mammal fauna has been conducted by DEC since 1998, in conjunction with Chevron (and formerly West Australian Petroleum Limited), by annual trapping. Staff of Chevron that work on Barrow Island have had the opportunity to become directly involved with the monitoring of the island fauna and are made aware of the conservation significance of the island at their induction. Some of the fauna monitoring has now been contracted externally but DEC staff are now present on the island (since 2010) and are actively involved and regularly consulted.
It had been recommended that monitoring of the three species be carried out every three years (Short 1995; Maxwell et al. 1996; Friend and Orell 1997). DEC chaired a workshop to discuss future monitoring regimes for the threatened mammals on Bernier and Dorre Islands in July 2003, with participants from DEC, CSIRO and AWC. A consensus was reached that regular monitoring was important. Over the last five years (2006-2011) DEC has adopted a cohesive approach to regular monitoring and conducted an annual population census on Bernier and Dorre Island for all three species.
Captive breeding and reintroductions
As detailed in Appendix 1 a number of captive and reintroduced populations have been established or attempted for the western barred bandicoot, burrowing bettong and banded hare-wallaby, in WA, SA and NSW.
Captive groups provide animals for reintroductions, research and educational activities. Captive breeding of burrowing bettongs employing minimal husbandry has been very successful at Heirisson Prong, RTDBF, and Yookamurra and Scotia WS. More intensive captive breeding of western barred bandicoots at PCBC and Kanyana Wildlife Rehabilitation Centre has met with a lesser degree of success due to lower than expected productivity, overcrowding (due to postponed releases) and disease (Morris et al. 2004). Mawson (2004) regarded banded hare-wallabies as potentially unsuitable for extensive pen systems (e.g. RTDBF) due to the risk of avian predation (Friend and Beecham 2004), while intensive pen systems were more successful (e.g. PCBC) but associated with a much higher cost of production.
With the establishment of a number of populations of western barred bandicoots, burrowing bettongs and banded hare-wallabies on islands and within extensive fenced areas, the need for captive breeding for future stocking of reintroduction sites may be reduced. Resources may then be better directed to managing reintroduction sites.
The reasons for previous re-introduction failures have been assessed and the results used to modify aspects for future re-introductions, including: site locations, site management, fence design, numbers of animals, method of release, and ongoing monitoring.
Details of the previous and current reintroductions attempts and captive breeding groups are provided in Appendix 1.
Workshops on Disease in Western Barred Bandicoot Populations were hosted by DEC’s WA Wildlife Research Centre in July 2002 and 2003, after the discovery of symptoms of two diseases in wild and captive populations led to concerns regarding the conservation of this species and others. Friend (2002) provided a summary of evidence and symptoms of the diseases and future management and research directions in his report on the workshop.
Resulting actions undertaken from the workshops included:
the preparation of a disease risk management strategy for future trapping, translocation and captive breeding work in WA (Chapman et al. 2008);
the euthanasia of western barred bandicoots diseased animals held in captivity or at reintroduction sites
provision of the euthanased animals to Murdoch University for further research; and
a halt to all future translocations of the western barred bandicoot from diseased populations, pending further research into the papilloma-like syndrome.
Recovery team meetings in 2005 and 2007, and a further symposium on western barred bandicoot research was held at Murdoch University in February 2007 to outline current conservation and research effort (Bennett 2007).
Completed research into disease includes:
research into toxoplasmosis, at Murdoch University,
investigation of the incidence of Chlamydia in western barred bandicoots on Dorre and Bernier Islands (Kutlin et al. 2007).
investigations to identify the cause of the papilloma-like syndrome, by Murdoch University (Bennett et al. 2008; Woolford et al. 2007; Woolford et al. 2008)
The disease risk management strategy does not address the issue of possible spread of disease by members of the public visiting Bernier and Dorre Islands. This threat is being addressed as a new recovery action in the plan.
Fox baiting techniques have been established by DEC with significant success. The Western Shield program (see section 2.1) includes fox baiting over an area of 3.5 million ha is ongoing. Sites relevant to shark bay marsupials which are covered by this program include Lorna Glen where translocations have occurred of burrowing bettong in 2010 and 2011.
Feral cat control
Studies on feral cat control include trials of methods of trapping, the use of a variety of baits and lures, and poisoning (Algar and Sinagra 1996; Risbey et al. 1997; Short et al. 1997b; Short et al. 2002; Arid Recovery Project 2002; Algar et al. 2002; Algar and Burrows 2004). In particular, DEC has developed kangaroo sausage baits for feral cats, impregnated with 1080 that have shown considerable signs of success in controlling cat numbers (Algar and Burrows 2004). The new cat baits, Eradicat®, are currently being considered for registration by the APVMA (Australian Pesticides and Veterinary Medicines Association). CSIRO had some success in controlling cats using mouse carcasses impregnated with 1080 poisoned ‘one-shot oats’ (Short et al. 1997b). Both methods worked well when applied in late autumn when prey abundance (rabbits) was low. Improvements in the design of barrier fences over time have also led to increased success in maintaining mainland areas free from predator incursions.
Successful cat control has been achieved on some islands (Burbidge and Manly 2002) especially where prey species are absent or limited. However, the broadscale application of cat control methods in the arid and semi-arid zones of the mainland has so far met with varied success. For example, an aerial baiting trial of DEC’s kangaroo sausage baits was carried out in 2002 in a buffer zone surrounding the ARP at 5% bait intensity used by DEC. Track transects indicated a 100% decrease in cat activity after the baiting; however, re-invasion was rapid and by three months post-baiting, there was no difference between control and baited track transects (Arid Recovery Project 2002). Similarly, Morris et al. (2004) reported an 80% reduction in cat numbers at François Peron National Park in 2002; however, the remaining number of cats was regarded as too high to consider the reintroduction of ‘cat-vulnerable’ species such as western barred bandicoots and banded hare-wallabies. In contrast, malleefowl and greater bilbies have been successfully established at Peron Peninsula despite the resident cat population, suggesting that these species are less vulnerable to cat predation.
The future success of mainland reintroductions of a range of species such as those reintroduced at Heirisson Prong, Peron Peninsula and Dryandra Woodland are dependent on the development of more effective methods of cat control. Until that time, exclusion fencing remains a key strategy for protection of mainland populations of threatened mammals.
Community involvement, education and knowledge transfer
A cross-cultural workshop was held at Yulara in September 1999 entitled Biodiversity and the Re-introduction of Native Fauna at Uluru - Kata Tjuta National Park (Gillen et al. 2000) to identify and discuss the issues surrounding the re-establishment of locally extinct fauna within the Uluru - Kata Tjuta National Park. This has led to the establishment of a predator-free enclosure and reintroduction of rufous hare-wallaby, with involvement of Anangu, the Mutijulu community, and Green Corps.
Strong and ongoing community participation in the Heirisson Prong project resulted in the ULCBPG and partners winning the 2001 Gold Banksia Award for Environmental Achievement and the 2001 Banksia Award for Community Group Achievement. Community members manage the day-to-day running of the conservation reserve, including predator control, maintenance of the predator-proof barrier fence, track maintenance and monitoring of predator incursions. They participate also in the monitoring of reintroduced western barred bandicoots and burrowing bettongs.
The Friends of Arid Recovery was established in 1998 and is involved in the project, producing a quarterly newsletter, coordinating volunteer involvement, staffing information displays, applying for funding, organising fundraisers and conducting working bees at the ARR (Arid Recovery Project 2002). They also assist with fauna and flora monitoring and management of the Reserve. There is a display focusing on the achievements of the ARP and the reintroduced mammals. ARP have hosted Earthwatch Institute expeditions since 2003, with volunteers assisting with research at the Reserve, and support a number of university students, from the University of Adelaide, and through the International Student Volunteer program (Arid Recovery 2004).They have shared in a number of awards, including the National Australia Bank Community Link Award in 2002 and one of the Prime Minister’s Awards for Excellence in Community Business Partnerships in 2003. A viewing platform and hide, and interpretive signage have been constructed at the Arid Recovery Reserve.
The Project Eden Community Advisory Committee was established with the inception of Project Eden, but the group has remained dormant for some time. However, Project Eden has been extremely active in community education through the regular involvement of local schools in reintroduction activities, school presentations and fundraising support, public talks and hands on presentations of threatened species during school holiday activities, as well as annual teacher professional development programs in recent years. Annual Landscope Expeditions, TAFE field training and Bushranger cadets programs have also been a regular feature of the Project, as well as dozens of individual volunteer and work experience placements, including long-term arrangements for credited internship placements with several tertiary Conservation and Biology degree programs.
A World Heritage Interpretation Centre was constructed in Denham, Shark Bay in 2006, to enable visitors to learn more about the area and to appreciate its distinctive values.
AWC have strong community support, and conservation programs are funded through public donations. Volunteer programs are well established and education programs are established at some AWC properties.
Population viability analysis
A population viability analysis was undertaken by Richards (2004), to examine future options for the recovery of the western barred bandicoot. Populations were modeled under a variety of scenarios to examine the possible effects of changes in carrying capacity, founder population size, inbreeding depression, and the occurrence of drought and cat predation as catastrophes, on the probability of population extinction. The analysis highlighted that cat predation was the most significant factor influencing breeding age, survivorship and overall population viability (Richards 2004).
DEC conducted out-breeding trials of western barred bandicoots from Bernier and Dorre Islands at Kanyana between 1994 and 1997, with fertile F1 offspring produced (Friend and Beecham 2004). Western barred bandicoots from Bernier and Dorre Islands have been cross-bred by DEC and maintained at the RTDBF. An evaluation of the benefits and ethics of cross-breeding needs to be made by DEC and additional stakeholders, prior to further implementation of hybridisation, as suggested by Spencer and Moro (2001). Burrowing bettongs from the two Shark Bay islands have been reintroduced at the ARR and Yookamurra WS, setting a precedent for future hybridisation at other sites. The population established at Lorna Glen is a product of animals sourced from Dorre Island and Barrow Island. University of Western Australia PhD student Felicity Donaldson is examining the level of genetic divergence between Bernier and Dorre Island burrowing bettongs (Donaldson and Vercoe 2008), to determine whether hybridisation of the two populations is acceptable. Results from this study are in preparation for publication and currently not available.
A genetic study of wild and reintroduced western barred bandicoots has revealed extremely low levels of genetic diversity in the wild Bernier and Dorre Island populations amongst the lowest ever recorded for marsupials (Smith and Hughes 2008). The reintroduced Heirisson Prong population has a similar level of genetic diversity to the source population (from Dorre Island), whereas the DFBF population exhibit a level of microsatellite diversity almost twice that of either of the founder populations (hybridised from Bernier and Dorre Islands) as a result of crossbreeding. However, this crossing of the two islands did not appear to result in an increase in the diversity of mitochondrial DNA (Smith and Hughes 2008). The reintroduced and captive populations of P. bougainville at Heirisson Prong and Peron Peninsula represent attempts to maintain the distinctiveness of historically isolated evolutionary lineages. Given the shallow divergence of the natural populations, the management emphasis should concentrate on maximizing diversity for reintroduction attempts without the fear of outbreeding issues or of disrupting local adaptations (Smith and Hughes 2008).
Recent DNA work on banded hare-wallabies by Westerman et al. (2002), has confirmed the unique taxonomic status of this species, although Prideux may have questioned this again in 2004. Work has also been done on sperm morphology and DNA of banded hare-wallabies by Dr Steve Johnstone at the University of QLD. The complete mitochondrial genome of banded hare-wallabies was mapped by Nilsson (2006).