San Diego Union-Tribune (Sunday)

STUDY: 20% OF REPTILE SPECIES WORLDWIDE FACE RISK OF EXTINCTION

Scientists cite habitat loss as largest factor

- BY CATRIN EINHORN Einhorn writes for The New York Times.

About 20 percent of reptile species risk extinction, mainly because people are taking away their habitats for agricultur­e, urban developmen­t and logging, according to the first global reptile assessment of its kind.

From inch-long geckos to the iconic king cobra, at least 1,829 species of reptiles — including lizards, snakes, turtles and crocodiles — are threatened, the study found.

The research, published Wednesday in Nature, adds another dimension to a substantia­l body of scientific evidence that points to a humancause­d biodiversi­ty crisis similar to climate change in the vast effect it could have on life on Earth. “It’s another drumbeat on the path to ecological catastroph­e,” said Bruce Young, co-leader of the study and a senior scientist at Natureserv­e, a nonprofit conservati­on research group. Such a collapse threatens humans because healthy ecosystems provide necessitie­s like fertile soil, pollinatio­n and water supplies.

Among reptiles, particular­ly hard-hit are turtles, with almost 60 eprcent of species at risk of extinction, and crocodiles, with half. In addition to habitat loss, both groups are depleted by hunting and fishing.

But the results also brought a sense of relief. Scientists have known far less about the needs of reptiles as compared with mammals, birds and amphibians, and they had feared the results would show reptiles slipping away because they required different conservati­on methods. Instead, the authors were surprised at how neatly the threats to reptiles overlapped with those to other animals.

“There’s no rocket science in protecting reptiles; we have all the tools we need,” Young said. “Reduce tropical deforestat­ion, control illegal trade, improve productivi­ty in agricultur­e so we don’t have to expand our agricultur­al areas. All that stuff will help reptiles, just as it will help many, many, many other species.”

The authors found that climate change played a role in the threat faced by 10 percent of species, suggesting that it was not currently a major factor in reptile loss. But the effects could be underrepre­sented, Young said, because scientists simply do not know enough about many reptiles to determine whether a warming planet threatens them in the short term.

What is clear is that the victims of climate change, reptilian and otherwise, will increase dramatical­ly in coming years if world leaders keep failing to adequately rein in greenhouse gas emissions, which mostly come from burning fossil fuels. In September, the Komodo dragon, the largest lizard in the world, was classified as endangered in large part because of the rising temperatur­es and sea levels caused by climate change.

The reptile assessment includes 52 authors with contributi­ons from more than 900 experts around the world. It took more than 15 years, in part because funding was hard to come by.

“Reptiles, to many people, are not charismati­c,” Young said. “There’s just been a lot more focus on some of the more furry or feathery species.”

The team ultimately assessed 10,196 species. In 48 workshops between 2004 and 2019, groups of local specialist­s would gather and evaluate species one by one. The findings for each reptile were reviewed by a scientist familiar with the species but not involved with the assessment, and then again by staff from the Internatio­nal Union for Conservati­on of Nature’s Red List of Threatened Species, the most comprehens­ive global catalog of the status of animal and plant species.

With 21 percent of species threatened with extinction, reptiles were found to be at higher risk than birds (of which about 13 percent of species are threatened with extinction) and slightly less than mammals (25 percent). Amphibian species, which have suffered from severe disease in addition to other effects, fare significan­tly worse, with about 40 percent of species in danger of extinction.

The assessment fills an important gap, said Alex Pyron, an evolutiona­ry biologist at George Washington University who focuses on reptile and amphibian biodiversi­ty and was not involved in the research. “This allows us to paint a much more detailed picture than was possible before,” Pyron said.

 ?? KAMRAN JEBREILI AP ?? A dead green sea turtle washes up on a beach at a conservati­on reserve in the United Arab Emirates.
KAMRAN JEBREILI AP A dead green sea turtle washes up on a beach at a conservati­on reserve in the United Arab Emirates.

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