The world's largest conservation group has opened a week-long meeting in Bangkok Wednesday, warning nearly 16,000 species face extinction.

The World Conservation Union kicked off its congress Wednesday by releasing its so-called Red List of Endangered Species. It has nearly 16,000 plants and animals listed. Indonesia, China and Brazil have the most threatened species.

The report says one in every four mammals and one in every eight birds are facing a high risk of extinction in the near future. While one in three amphibians and almost half of all tortoises and fresh water turtles are threatened. In the last 500 years some 844 species have died out. Conservationists are sounding the alarm as the current rate of extinction far exceeds that.

 Achim Steiner is Director General of World Conservation Union. "The evidence presented in this Red List should make people worried about the future viability of many of the eco systems on which we depend," he said. "The loss of biodiversity means a great deal to those who understand the implications of that loss."

Experts attribute the problem to climate change and destruction of natural habitats by human encroachment. The union's report says half of the world's wetlands have been destroyed over the last 100 years and more than a quarter of the world's coral reefs have been destroyed. This congress - which brings together scientists, activists and government officials from 181 countries - is debating how best to address these problems over the next fours years.

The union's Mr. Steiner says governments need to start paying attention conservationist ideas. "The world's conservation community has been ignored for far too long by those who are taking fundamental decisions in the economic and political sphere," he said.  

Conservationists say their efforts are working. On the good news front one quarter of the world's threatened birds have benefited from conservation efforts, and several species have started to recover. The eight-day congress will close on November 25.