Chimpanzee researcher Jane Goodall says Bush administration policies could lead to more hunting of endangered animals.
Delivering the keynote speech at the Foothill College in Los Altos Hills, California, Goodall said: "What the Bush administration has done over the past three years to overturn environmental laws is unbelievable. It's shameful. We must not sit still and do nothing."
She said the administration's interpretation of the Endangered Species Act could allow people to hunt endangered animals in other countries, as long as US interests pay the other countries to help fund conservation programmes.
"This will mean it's going to be possible to shoot any of the endangered animals and just say the money goes to conservation," Goodall said. "It stinks, quite honestly."
Goodall has spent more than 40 years researching the lives of chimpanzees in Tanzania.
She was recently named a United Nations Messenger of Peace and travels the world speaking in favour of environmental causes.