On an uninhabited island in the southern Bahamas, a scientist noticed a snake that shined like metal as it climbed a tree.

“We all came to take a look at it, and it was instantly clear that this was something different,” says biologist R. Graham Reynolds, part of the scientific team exploring the remote islands.

Expedition member Alberto Puente-Rolón, an expert on Caribbean boas, agreed that the animal appeared unlike any species of known boa.

So the team went searching for more boas, finding four more snakes before settling down to sleep on the beach at Conception Island. But it turns out the boas weren't ready to call it a night. (See "Extremely Rare Fishing Snakes Discovered.")

“Sometime around 3:30 in the morning, I woke up to something crawling across my face,” says Reynolds, now a biologist at the University of North Carolina, Asheville.

Another silver boa had come down from the forest and crawled right over him as he slept. They'd located their sixth specimen, and DNA analyses back at the lab confirmed the snake was a new species.

The scientists named the Conception Bank silver boa (Chilabothrus argentum), based on both its color and the fact it was first found on an aptly named silver palm tree. A study on the species appeared in the journal Breviora.

“This discovery is significant because of how well-studied many parts of the Bahamas are, especially in terms of herpetology,” says Julie Ray, director of the conservation group Team Snake Panama.

On the Edge

The three other Bahamian boa species look different from the newfound species, with dark splotches and stripes. The silver boa is not only paler, it also—unlike the others—lives in trees, where it feeds mostly on birds.

“This new species occurs on a group of islands that have never been connected to any of the other islands in the Bahamas,” says Reynolds. “As far as we know, they only occur on Conception Island Bank and nowhere else.” (See "Why We Were Totally Wrong About How Boa Constrictors Kill.")

Thus, the entire silver boa population, which the team estimates to be fewer than a thousand animals, is found only in one small patch of Earth.

If You're Scared of Snakes, Don't Watch This Every year, thousands of snakes gather at the Narcisse Snake Dens in Manitoba, Canada.

This makes the species vulnerable to extinction, and Reynolds and his colleagues believe the silver boa should be designated as critically endangered by the International Union for Conservation of Nature.

Silver Lining?

Fortunately for the silver boa, all islands on the Conception Island Bank are national parkland, and visitors to the area are relatively rare.

Reynolds and his colleagues are working with the Bahamas National Trust, which administers the national parks, on strategies to protect the species.

The reptile faces threats such as natural disasters (which could wipe out the entire population); poaching for the pet trade; and feral cats, which exist on Conception Island and are known to prey on boas elsewhere in the Bahamas. (Also see "Island's Feral Cats Kill Surprisingly Few Birds, Video Shows.")

View Images The silver boa lives in trees, where it feeds mainly on birds. Photograph by R. Graham Reynolds, University of North Carolina, Asheville

Ray agrees that despite living in a refuge, the boa is still in danger—in particular from feral cats and dogs.

“All efforts should be made to restrict the number of dogs on the island and how freely they are allowed to roam,” says Ray.

“More importantly, an attempt should be made to remove the feral cats from this protected natural area because they are not native predators.”