At least one in five reptile species are threatened with extinction, including more than half of turtles and crocodiles, according to the first major global assessment of the world’s so-called cold-blooded creatures.

Catastrophic declines in biodiversity across the world are increasingly seen as a threat to life on Earth — and as important as the interrelated menace of climate change.

Threats to other creatures have been well documented. More than 40 percent of amphibians, 25 percent of mammals and 13 percent of birds could face extinction.

But until now, researchers did not have a comprehensive picture of the proportion of reptiles at risk.

In a new global assessment, published in the journal Nature, researchers assessed 10,196 reptile species and evaluated them using criteria from the International Union for Conservation of Nature (IUCN) Red List of threatened species.

They found that at least 1,829 — 21 percent — were either vulnerable, endangered or critically endangered.

“It’s just overwhelming the number of species that we see as being threatened,” said co-author Neil Cox, who manages of the […]