Four hundred years ago Dirk Hartog, a captain with the Dutch East India Company, landed on the Western Australian coast on what is now called Dirk Hartog Island. The island was visited by further explorers including Willem de Vlamingh and William Dampier.
Dirk Hartog Island, now a national park in the Shark Bay World Heritage Area, is Western Australia’s largest island. It is 80 km long and 15 km at its widest point with an area of about 63,000 hectares.
When these early explorers landed on the island there were, according to subfossil records, 13 native mammal species living there. Today there are just three. The local extinctions have been the result of human activity including the introduction of goats, sheep and cats. By 2009, when it became a national park, the island’s goat population had expanded to an estimated 10,000 and the impact of these animals grazing and trampling on the native vegetation had been very severe.
“Return to 1616” is an ambitious $16.3 million project to eradicate all feral animals from the island and return the 10 locally extinct species – including the Woylie, Chuditch (Western Quoll), Dibbler and Western Barred Bandicoot – to the island. There are also plans to introduce two other threatened species, the Banded Hare-wallaby and the Rufous Hare-wallaby, from neighbouring islands in order to aid their conservation.
Two-thirds of the funding for the project comes from an offset which was a condition for Chevron’s Gorgon gas project on Barrow Island and a third from Western Australia’s Department of Parks and Wildlife.
The project has used a variety of methods to remove the feral animals. “Judas” goats wearing radio collars have been used to locate goats for aerial shooting programs. Methods such as pheromone lures and mouse sound effects have been used to trap cats while baiting has also eradicated many of these pests. Infra-red motion cameras and cat-detector dogs have also been used to detect cats.
Species introduction will only take place after the project operators are sure that the cat menace has been completely removed and the native vegetation has had time to recover.
- Leonie Blain
This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on September 26, 2016