The world's mammals are in the grip of an extinction crisis, with almost one in four at risk of vanishing forever, according to the latest scientific assessment revealed at the International Union for the Conservation of Nature's World Conservation Congress, which opened Sunday in Barcelona.
The new study conducted for the IUCN Red List of Threatened Species for the first time assessed all of the 5,487 mammals on Earth and found that at least 1,141 of them are known to be threatened with extinction. At least 76 mammals have become extinct since the year 1500.
The real situation could be much worse as 836 mammals are listed as Data Deficient. With better information, scientists may classify even more species as being in danger of extinction.
"The reality is that the number of threatened mammals could be as high as 36 percent," said Jan Schipper of Conservation International, lead author in a forthcoming article on the mammal assessment in the journal "Science."
"This indicates that conservation action backed by research is a clear priority for the future, not only to improve the data so that we can evaluate threats to these poorly known species, but to investigate means to recover threatened species and populations," said Schipper.
The project to assess the world's mammals was conducted with help from more than 1,800 scientists from over 130 countries. The assessment also indicates that conservation can bring species back from the brink of extinction, with five percent of currently threatened mammals showing signs of recovery in the wild.
The results show 188 mammals are in the highest threat category of Critically Endangered, including the Iberian Lynx, Lynx pardinus, which has a population of between 84 and143 adults and has continued to decline due to a shortage of its primary prey, the European rabbit, Oryctolagus cuniculus.
It may be too late to save the 29 species that have been flagged as Critically Endangered Possibly Extinct, including a rodent once found in Cuba, the Little Earth Hutia, Mesocapromys sanfelipensis, which has not been seen in nearly 40 years.
Nearly 450 mammals have been listed as Endangered, including the Tasmanian devil, Sarcophilus harrisii, which was moved from the category of Least Concern to Endangered after the global population declined by more than 60 percent in the last 10 years due to a fatal infectious facial cancer.
Habitat loss and degradation affect 40 percent of the world's mammals. It is most extreme in Central and South America, West, East and Central Africa, Madagascar, and in South and Southeast Asia. Over harvesting is wiping out larger mammals, especially in Southeast Asia, but also in parts of Africa and South America.
The assessment of the world's mammals shows that species can recover with concerted conservation efforts. The black-footed ferret, Mustela nigripes, moved from Extinct in the Wild to Endangered after a successful reintroduction by the U.S. Fish and Wildlife Service into eight western states and Mexico from 1991-2008.
"We are now emerging from the dark ages of conservation knowledge, when we relied on data from a highly restricted subset of species," says Dr Jonathan Baillie, director of conservation programs at the Zoological Society of London. "In the future we will expand the scope of our species knowledge to include a far broader range of groups, thus informing and assisting policy makers in a hugely more objective and representative manner."