LONDON, Feb. 15 (UPI) -- Nearly a fifth of reptile species across the globe are at risk of extinction, researchers at the Zoological Society of London say.

Their study, based on a random sample of 1,500 of the world's reptile species, indicated the future of 19 percent of the world's reptiles is threatened, the BBC reported Friday.


"It's essentially [like] an election poll setup -- using this sample to give an example of how reptiles are doing as a whole," lead study author Monika Bohm said.

Many of the estimated 9,500 reptile species in the world can be "indicators" of environmental problems, she said.

"Reptiles are often associated with extreme habitats and tough environmental conditions, so it is easy to assume that they will be fine in our changing world," she said.

"However, many species are very highly specialized in terms of habitat use and the climatic conditions they require for day-to-day functioning. This makes them particularly sensitive to environmental changes."

The study, published in the journal Biological Conservation, was conducted in cooperation with 200 experts from the International Union for the Conservation of Nature's Species Survival Commission.

In addition to the species facing extinction, 47 percent of the world's reptile species are considered "vulnerable," they said.