Not even Snake Island is a true safe haven for rare vipers

Snake Island off the coast of Brazil may seem like an ideal animal sanctuary. The small island, which measures around 110 acres, is inhabited by some 4,000 golden lancehead pit vipers, which are critically endangered and are endemic to this one strip of land surrounded only by blue water.

Access to the island is denied to everyone save for a select few scientists, who frequent the island to check up on the health of the snakes and occasionally milk them for their venom, which is then used in several lifesaving medications for people.

Then again, you’re better off staying clear of Snake Island. The vipers’ venom is highly toxic: even a minute amount of it in your bloodstream will cause you to suffer a painful death. Local fishermen stay well clear of the island, telling tales of people who decided to set foot on it in search of lost pirate treasure, never to be seen again.

So the snakes, which feed primarily on small birds, are safe and sound in their splendid isolation. Not so.

Many of the birds that arrive on the island and end up being food for the snakes originate on the mainland in Brazil, which lies some 33km away. Land clearing there has decimated local forests, robbing the birds of their natural habitats. The numbers of migrating birds doing stopovers on Snake Island have plummeted and with fewer birds, the snakes have less food to eat.

“Just in the five-year cycle that I’ve been studying I can see changes on this island,” says Australian snake expert Bryan Fry, who regularly visits Snake Island. “And it’s really, really depressing for someone like me who is just in love with these kinds of animals,” adds Fry, who has been dubbed Venom Doc for his great interest in snake venoms and their applications in medicine.

“But this is an unnatural disaster,” Fry stresses. “This is a manmade catastrophe that is symptomatic of what is going to happen to the rest of the world.”

Even if you have little love for venomous reptiles, it is still in your interest to see snakes saved from extinction around the world, the Australian expert stresses. “Lanceheaded vipers have already been responsible for lifesaving medications,” Fry says. “For example, if you know of anyone who is taking high-blood pressure medication, odds are that they are taking captopril or its derivatives,” he explains. “This is a drug class built off of the toxins from lanceheaded vipers.”

He adds: “This reinforces why we need to conserve all of biology, because we can’t predict where the next wonder drug is going to come from.”