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
