CANBERRA, Nov. 21 (Xinhua) -- Animals bred in captivity develop physical and behavioral changes that inhibit their ability to survive in the wild, Australian scientists have discovered.
In research published on Monday, a team from Australian National University (ANU) found that captive environments "drastically" alter selection pressures on animals.
Examples highlighted by the review of international and Australian research include captive-bred lions with different skull bone shapes and weaker bite force than those in the wild.
The wing shape of the critically endangered orange-bellied parrot, which is endemic to southern Australia, has changed in captivity.
For another critically endangered native bird, the regent honeyeater, songs are shorter and less complex among males bred in captivity, making them less attractive to mates in the wild.
Dejan Stojanovic, a conservation biologist at the ANU College of Science and co-author of the study, said the trend has gone unnoticed for decades.
"It's a global thing that affects everything from butterflies through to elephants," he told the Guardian Australia.
"Between 1999 and 2009, 423 orange-bellied parrots were released at Birch's Inlet near Strahan in western Tasmania, and all of them died."
Stojanovic, who has studied the breeding biology of orange-bellied parrots for years, and his team are now analyzing whether the change in the wing shape is linked to high mortality when they migrate between Tasmania and the mainland.
Responding to the study, Zoos Victoria reproductive biologist Marissa Parrott, said captive breeding was essential for conservation efforts and that recent scientific advancements have resulted in programs that better approximate the wild environment. ■
