Western Australia’s coastal islands survey reveals surprising biodiversity & 27 new species of snail – Possible solution to Cane toad problem

- Land snail expert Roy Teale and DEC ecologist Mark Cowan with an olive python – Photo courtesy Lesley Gibson, DEC.

April 2009. An ambitious survey is revealing extraordinary details about the fauna, flora and ecology of the islands along the Kimberley coast in the hope they could play a key role in the conservation of the region's native plants and animals.

Western Australia's Department of Environment and Conservation (DEC) biologists are conducting a comprehensive biological survey of selected islands off the north Kimberley coast, focusing on fauna that is likely to be affected by cane toads and other mainland threats.

The survey team has completed two dry season and wet season surveys on 13 islands from Sir Graham Moore Island in the north to Augustus Island in the south, with a further survey of nine islands planned for this dry season.

Rich in frogs and snakes
DEC senior research scientist Lesley Gibson said the survey has so far revealed the presence of additional island populations of many animals, particularly snakes and frogs, and has more than doubled the species lists for most of the islands visited.

Northern quoll - Agile wallaby - Merten's water monitor
"We recorded a northern quoll on Adolphus Island, which is a significant record as this species has dramatically declined on the adjacent East Kimberley mainland," Dr Gibson said.

The agile wallaby on Adolphus Island and Merten's water monitor on Augustus Island were also recorded for the first time on Western Australian islands.

Northern Quoll. Credit DEC.

Dr Gibson said that while the mainland had been impacted by various threatening processes, the islands were largely protected. She added "Biodiversity on the mainland Kimberley is under threat from extensive dry season wildfires, feral animals, weeds, soil erosion and the imminent invasion of the cane toad. The islands support populations of plant and animal communities that are in relatively good condition and hence have high conservation value, but little was known before this survey about what plant and animal species occur on the islands.

Safe havens
"The survey is being conducted in the hope that intact ecosystems can be conserved and that in the future the islands could provide a safe haven for threatened species from the mainland. The survey is also contributing to the State Government's $9 million Kimberley Science and Conservation Strategy by providing fundamental biodiversity information on the islands off the Kimberley coast."

The survey has attracted $2.7 million in Federal Government funding through the Natural Heritage Trust, while the State Government has contributed $4.3 million.

Support has been provided by the Kimberley Land Council and Aboriginal groups, the Western Australian Museum, and the Australian Museum.