Dibblers return to their island home, circa 1616

This is the story of the tiny dibbler, the scientist and the wiliest of cats that grew fat on the hatchlings of ­endangered turtles.

Dirk Hartog Island has been cleared of feral cats to receive native dibblers bred at Perth Zoo. Picture: Perth Zoo

This is the story of the tiny dibbler, the scientist and the wiliest of cats that grew fat on the hatchlings of ­endangered turtles.

A decade ago, Dirk Hartog Island off Western Australia was overrun with pet cats gone wild and their descendants. The cats, which possibly arrived on the boats of early explorers or ran away from the homestead of the island’s former sheep station, are blamed for wiping out 10 of the 13 native species thought to have been there when Dutch explorer Dirk Hartog arrived on the Eendracht on October 25, 1616.

Among the animals to become locally extinct was the dibbler, one of Australia’s smallest marsupials. Next week, 27 dibblers bred at Perth Zoo are due to arrive on a helicopter at Dirk Hartog Island for a cat-free life 850km northwest of Perth.

The zoo bred the dibblers as part of a plan to return the island’s habitat to the way it was in 1616.

The McGowan government hoped to give shelter and security to species that would have otherwise struggled to survive.

“Dibblers may be small, but these carnivorous marsupials play a very big role in the ecosystem — they are predator and prey, and also pollinators in their habitat,” WA Environment Minister Stephen Dawson said on Tuesday.

It cost the previous Barnett government almost $17m to track, trap and humanely kill the cats on Dirk Hartog Island before nat­ive species could be reintroduced.

Much of the work was done by ecologist Sue Robinson and her tracker dogs, so highly trained they cost up to $20,000 each. The dogs did not attack cats but sniffed out their faeces so that Dr Robinson knew where to lay traps.

Marsupials were all but gone from the island when she and her colleagues arrived in 2015 but the cats had found other things to eat. The most difficult cat to find was a male that left tracks daily at the island’s loggerhead turtle nesting ground, Mystery Beach.

Known as MB8, it had been fitted with a GPS data logger under its skin so scientists could study its habits, but it fed on so many loggerhead turtle hatchlings it grew a thick layer of fat that weakened the GPS signal before scientists found it in a rockhole and shot it.