Hundreds of threatened species not on official US list

Half of country's Red List mammals have no protection

December 2011: Many of the animal species at risk of extinction in the United States have not made it onto the country's official Endangered Species Act (ESA) list, according to new research from the University of Adelaide.

IGNORED: The critically endangered Kittlitz's murrelet, which is not on the ESA protection list. Picture: US Fish and Wildlife Service

National ‘red lists' are used by many countries to evaluate and protect locally threatened species. The ESA is one of the best-known national lists and arguably the world's most effective biodiversity protection law.

More than 500 animals have not made the list
A study - now published in the latest issue of Conservation Letters - has compared the ESA list of endangered species with the world's leading threatened species list, the International Union for the Conservation of Nature (IUCN) Red List.

The study has found that of the American species included on the IUCN Red List, 40 per cent of birds, 50 per cent of mammals, and 80 to 95 per cent of other species such as amphibians, gastropods, crustaceans, and insects, were not recognised by the ESA as threatened.

This amounts to approximately 531 American species on the IUCN Red List that have not made the ESA protection list. These include bird species such as the critically endangered Kittlitz's murrelet, the endangered ashy storm-petrel and the vulnerable cerulean warbler.

Vague definitions of 'endangered' and 'threatened'
‘The ESA has protected species since its establishment in 1973, and it may have prevented 227 extinctions. However, the implementation of the ESA by successive US governments has been problematic, including poor coverage of imperilled species, inadequate funding, and political intervention,' says study leader Bert Harris, a native of Alabama who is undertaking his PhD with the University of Adelaide's Environment Institute and School of Earth & Environmental Sciences.

‘Vague definitions of "endangered" and "threatened" and the existence of a "warranted but precluded" category on the ESA list are also contributing to the gap in species classification,' he says.

Mr Harris says a detailed evaluation of the ESA's coverage of the IUCN Red List was ‘well overdue'.

‘The IUCN Red List is imperfect, but it is the leading global threatened species list. It involves collaboration of many scientists, and regular refinement of its categories and criteria,' Mr Harris says.