Supporting the KI Dunnart Project
The KI Landscape Board have started a new project to support the recovery of the Kangaroo Island dunnart.
The Kangaroo Island dunnart (Sminthopsis aitkeni) is listed in the Endangered category of the threatened species list under the Environmental Protection and Biodiversity Conservation Act 1999. It is the only species of dunnart found on Kangaroo Island and is endemic to the island. The current distribution is unknown, although since 1990, all records are from the western end of the Island within Flinders Chase National Park, Ravine des Casoars Wilderness Protection Area and remnant native vegetation on private land.
The new three-year project, supported by the KI Landscape Board through funding from the Australian Government’s Environment Restoration Fund will support the recovery of the Kangaroo Island dunnart following the 2019-20 bushfires, which burnt over 90% of their habitat on western Kangaroo Island. The project will also implement key management actions identified in the 2011 Recovery Plan and the 2019 draft Conservation Advice for the Kangaroo Island dunnart.
Priority actions will include determining the current distribution of the Kangaroo Island dunnart, identifying immediate and long-term threats to their persistence, and implementing management actions to reduce those threats.
To determine the distribution of the remaining KI dunnart population, the project will survey remaining unburnt habitat on western Kangaroo Island, as well as burnt sites where KI dunnarts had been detected before the fire. The project will also survey in unburnt parts of the island, where KI dunnarts were recorded historically on both public and private lands.
To survey for the presence of KI dunnarts, wildlife cameras placed facing drift line fences will be used to passively monitor wildlife as it passes by. The wildlife cameras are motion activated and infrared (near invisible to the naked eye), and take a series of images when an animal moves across the cameras field of view. Drift line fences are constructed of a 30 cm high and 30 m long section of flywire mesh, which encourages animals to move along it and in front of the camera. This has been found to be the most effective technique for detecting KI dunnarts (Hohnen et al. 2018) and has been standardised, so that survey effort is consistent all sites. To be confident in detecting KI dunnarts are present, sites are surveyed for 50 days. The survey technique is also highly efficient at detecting other species, with data collected assisting other projects to assess biodiversity recovery after the fire.
Monitoring the dunnarts
Initial survey effort focused on unburnt habitat, as this was thought to be the last remaining refuge for this species post-fire and to date 56 drift line sites have been surveyed, with 24 of these in unburnt habitat. Astonishingly, KI dunnarts have not only been detected at 22 separate drift line sites, they have also been recorded at three burnt sites where they had been before the fire.
The early success in detecting KI dunnarts and in particular the species apparent resilience to fire, is encouraging for the recovery of the species, but there are several known key threats that may have serious consequences in the short to medium term.
Feral Cat Control
Predation by feral cats is recognised as the key threat impacting the recovery of the KI dunnart [determined from the National Environmental Science Program (NESP) Bushfire Recovery Workshop held in February 2020 and the draft Conservation Advice (2019) for the Kangaroo Island Dunnart].
To reduce this critical threat, feral cat numbers are being controlled using various targeted techniques including, cage and soft jaw leg-hold traps, Felixer® grooming traps, ground shooting using thermal technology and detector dogs. Trials using various techniques, including Curiosity®
cat baits, will help refine feral cat control methods in fire affected landscapes and optimise application of techniques, based on humaneness, efficiency and impact. As the project progresses we will gain a better understanding of how effective different cat control methods are, and therefore if it is more feasible and more efficient to use one or more techniques in fire affected areas, compared to other control methods.
To date a total of 68 feral cats have been removed from 3,237 cage trap nights within or in close proximity to sites where KI dunnarts have been detected. The highest numbers of feral cats have been from sites along the Cape Borda Road within Ravine Des Casoars Wilderness Protection Area and Flinders Chase National Park, within or in close proximity to KI dunnart detection sites, however recent results suggest that feral cats are now moving out into the fire affected landscape. This period during winter coincides with the most effective time for feral cat control, when food sources are scarce and food demands are likely to be higher.
One of the reasons the KI Landscape Board is conducting the KI Feral Cat Eradication Program is because feral cats are not native to KI and prey upon many different native species, many of whom are threatened. Whilst monitoring for the KI dunnart, the team have also captured many threatened species on the motion-detecting cameras within the monitoring sites on the western end of the island. Below is a selection of some of the threatened species we managed to get a good photo of:
KI Recovery Team
This project will be overseen by the recently established KI Dunnart Recovery Team which will call upon the expertise of a selection of experts from the Department for Environment and Water, conservation groups like KI Land for Wildlife, the National Environmental Science Programme, the Australian Government and Zoos SA. The Recovery Team is responsible for the recovery planning process and to provide advice on the direction of KI dunnart recovery activities.
As part of a joint initiative between NPWSSA and the Atlas of Living Australia, all of the camera trap photos from the KI dunnart survey sites are now available on-line for citizen scientists to help look through and identify which animals are present.
If you would like to help out and get involved with a bit of citizen science input, please head on over to https://volunteer.ala.org.au/Bushfire-Recovery-Projects and help us ID some animals.
The KI Landscape Board
The Kangaroo Island Dunnart Recovery Team