A report from an international team of 174 scientists from 38 countries at the U.N. Convention on Biological Diversity in Nagoya says losses are due largely to human encroachment on habitat, over-fishing and over-hunting, The Christian Science Monitor reported Thursday.
The report also cited the impact of invasive species in habitats where natural inhabitants have evolved no defenses against the invaders.
Researchers examined 25,780 vertebrate species using the International Union for the Conservation of Nature's seven categories for a species' status from "least concern" to "extinct," and found that 52 species of birds, mammals and amphibians move one category closer to extinction each year, with the biggest losses in the tropics.
But the news is not all bad, researchers say, pointing to conservations efforts that have proved successful in stopping some of the declines and have brought other species a step close to recovery.
"The bad news can be extremely disheartening," Ana Rodrigues, a scientist with the Center for Functional and Evolutionary Ecology in Paris," says. "But our results show that conservation efforts are not wasted."