Scientists Study Why Koalas Are Picky Eaters

SYDNEY, Australia - Scientists trying to save Australia's dwindling koala colonies want to know why the marsupials eat leaves from certain eucalyptus trees and bypass others.

The wild population of Australia's emblematic animal, the delight of tourists, has been in rapid decline in this century and could vanish by the end of the decade, the Australian Koala Foundation says.

A three-year project launched today aims to identify the key chemical components that make only some of the trees palatable to koalas, the Australian Koala Foundation said.

The project was announced to coincide with Save the Koala Day today.

The project coordinator, biologist Bill Foley of James Cook University, said that not only do koalas eat relatively few species of eucalyptus, they cannot eat from every tree even within those species.

"We now know a lot more about the makeup of eucalyptus leaves than we did in the past and are confident that we can identify what makes one tree edible yet another unpalatable," Foley said.

"If we are going to reconstruct forests for koalas or rehabilitate sick or injured animals, then we need to know what makes a leaf good to eat."

Koala numbers in the wild have been plummeting. The furry marsupials were hunted for their pelts until 1930; during one hunting season in the 1920s, 3 million koalas were killed. More recently, housing and highways have encroached on their remaining habitat.

The Australian Koala Foundation estimates just 50,000 to 80,000 wild koalas remain in isolated, vulnerable colonies. It has warned they could be extinct by 2000, except in zoos and game preserves.