More species slide to extinction

The polar bear and hippopotamus are for the first time listed as species threatened with extinction by the world's biodiversity agency.

They are included in the Red List of Threatened Species published by the World Conservation Union (IUCN) which names more than 16,000 at-risk species.

Many sharks, and freshwater fish in Europe and Africa, are newly included.

The IUCN says loss of biodiversity is increasing despite a global convention committing governments to stem it.

"The 2006 Red List shows a clear trend; biodiversity loss is increasing, not slowing down," said IUCN director-general Achim Steiner.

"The implications of this trend for the productivity and resilience of ecosystems and the lives and livelihoods of billions of people who depend on them are far-reaching."

Overall, 16,119 species are included in this year's Red List, the most detailed and authoritative regular survey of the health of the plant and animal kingdoms.

This represents more than a third of the total number of species surveyed; the list includes one in three amphibians, a quarter of coniferous trees, and one in four mammals.

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