Protecting threatened quolls and other biodiversity on Kimberley islands from cane toads

Project Summary Project 4.2.5

Kimberley islands. Photo: Mark Cowan

Research in Brief Why is the research impacts when they reach islands and in relatively short time periods. This research will use existing needed? In combination, these factors mean data to predict future invasion Cane toads (Rhinella marina) have that keeping cane toads off currently by cane toads of Australian caused extensive declines and local uninvaded Australian islands is a high islands, particularly the Kimberley extinctions of many species on priority for conservation managers. islands. This information is mainland Australia. Both aquatic and important for prioritizing The endangered Northern Quoll terrestrial species that eat frogs or (Dasyurus hallucatus) was once surveillance action on these toads are highly at risk. islands in order to conserve widespread across Northern Australia toad-sensitive species such as Australia’s islands are important but many local declines have been the endangered Northern Quoll. conservation refuges which are rich observed following the invasion of in unique endemic species. Islands cane toads. Northern Quolls occur that are free from invasive species, on several islands across the northern particularly feral animals, have also Australian coast. Many islands in enabled some species to persist that Queensland and the Northern have become extinct on the mainland. Territory have already been invaded The value of islands as refuges from by cane toads. The more than invasive species has led conservation 2,500 islands off Western Australia’s managers to use them as arks to Kimberley coast are thought to be host insurance populations of highly cane toad free, although cane toads vulnerable mainland species. are known to have colonised at least one island. Protecting existing Islands can also be especially sensitive quoll populations on islands is likely to the impacts of invasive species, due to be important to the long term to the naivety of local animals and the conservation of the species. complex interrelationships between species. The result is that invasive The ability of cane toads to breed species can cause very large negative prolifically means that, eradicating Northern Quoll. Photo: Lesley Gibson established cane toad populations • Guide thinking about conservation is close to impossible. The greatest investments on islands that hope lies in keeping cane toads off could be impacted by future islands through biosecurity and using cane toad invasions surveillance to eradicate single toads or • Make decisions about toad- very small populations before they are avoidance training of existing able to establish. A difficulty lies in the Northern Quoll populations large number of islands and the cost on islands and logistics involved in surveillance. The research will produce a map Despite the significant consequences of Kimberley islands which includes of cane toads invading islands, a timeline of the expected year very little prior research has been of toad invasion for every island, undertaken on the distribution of along with a measure of certainty cane toads on Australia’s islands, about the predicted date. mechanisms and risk factors associated with cane toad invasion The research will be valuable to Cane Toad. Photo: Pavel Kirillov_Flickr_CC BY-SA 2.0 of islands, which islands are most at Kimberley island managers, especially risk, and which islands have the most the Traditional Owners (and their The findings will also be shared to lose. Filling these knowledge gaps respective Ranger programs) and with Traditional Owners of the is vital to underpin strategies and the West Australian Department Kimberley islands. actions to protect biodiversity of Biodiversity, Conservation on Kimberley islands. and Attractions, as well as the Where is the research Northern Quoll Recovery Team. How will the research happening? help? What research activities Modelling is being undertaken are being undertaken? at the University of Queensland This research will analyse the and is relevant to the islands of mechanisms and risk factors Key activities include: the Kimberley specifically and associated with cane toad invasion • Collation of existing data, other cane toad free islands in of Australian islands. The team will including on cane toad northern Australia generally. then develop a general model of invasion ecology and cane toad invasion for Australian Kimberley ocean currents When is the research islands to forecast cane toad invasion for Kimberley islands. • Modelling cane toad happening? invasion to Kimberley islands The work began in 2016 and The results of this work will support and factors shaping this Kimberley land managers to: will conclude in 2018. • Production of a map of • Identify the islands at most and Kimberley islands identifying least risk from invasion likely invasion dates Further Information • Identify pathways and potential For more information contact: arrival routes to the islands Who is involved? Prof Salit Kark • Prioritize expensive cane toad The work is being led by the [email protected] surveillance effort on islands University of Queensland in collaboration with the Western OR • Guide decisions regarding island Australian Department of Biodiversity, UQ PhD Candidate: selection for introductions of cane Conservation and Attractions. Matthew McKinney toad sensitive threatened species [email protected]

This project is supported through funding from the Australian Government’s National Environmental Science Programme.