BARCELONA, Spain — An “extinction crisis” is under way, with one in four mammals in danger of disappearing because of habitat loss, hunting and climate change, a leading global conservation body warned Monday.
“Within our lifetime, hundreds of species could be lost as a result of our own actions,” said Julia Marton-Lefèvre, the director general of the International Union for Conservation of Nature, or I.U.C.N., a network of campaign groups, governments, scientists and other experts.
Among 188 mammals in the group’s highest threat category — critically endangered — was the Iberian lynx, which has an estimated population of 84 adults and has continued to decline as its primary prey, the European rabbit, has fallen victim to disease and overhunting.
The report, presented at the World Conservation Congress in Barcelona, formed part of a Red List of Threatened Species issued annually by the group.
The fishing cat, found in Southeast Asia, was moved to the second most threatened category, endangered, from vulnerable, because of habitat loss in wetlands. The Caspian seal, also now endangered, has declined in population by 90 percent over the past 100 years because of unsustainable hunting and degradation of its habitats.
Jan Schipper, the director of the global mammal assessment for the I.U.C.N. and for Conservation International, an environmental group, said it was hard to draw a direct comparison with the last detailed survey on mammals, in 1996. New species have been identified, others discovered, and the criteria used to assess species have been made more broadly applicable across all animals and plants.
But he gave a mostly bleak assessment.
“Although 5 percent of mammals are recovering, what we observe are rates of habitat loss and hunting in Southeast Asia, Central Africa and Central and South America that are so serious that the overall rate of decline has steadily increased during the past decade,” Mr. Schipper said.
Amphibians, too, are facing an extinction crisis, with at least 33 percent either threatened or extinct, the I.U.C.N. reported.
Holdridge’s toad, found only in Costa Rica, was declared extinct. The Cuban crocodile, illegally hunted for its meat and skin, was moved to the critically endangered category.
Making the list for the first time were Indian tarantulas, highly prized by collectors and threatened by the international pet trade. The Rameshwaram parachute spider, whose habitat has been eroded by new roads, was found to be critically endangered. The spiders’ “natural habitat has been almost completely destroyed,” the group said.
Not every part of the report was bleak. The African elephant was removed from the vulnerable list and was listed as “near threatened,” although its status varied depending on location. The I.U.C.N. said increases in the population of the elephants in southern and eastern Africa were big enough to offset any decreases taking place elsewhere.