The Only Place on Earth Where You’ll Find This Particular Snake Species (and a Rumored 1 Snake for Every 10 Square Feet!)

If, like Indiana Jones, you’re not a fan of snakes, then you probably won’t be booking a trip to “Snake Island” anytime soon. Picture an entire island teeming with thousands of snakes — and not just any snakes, but deadly, venomous pit vipers. Where is this frightfully dangerous place, and just how treacherous is it? Let’s take a look at the infamous Snake Island and the notorious creatures that call it home!

Where Is Snake Island?

The island’s official name is Ilha da Queimada Grande, or “Big Burn Island,” although today, people often just call it “Snake Island.” Located about 20 miles off the coast of Brazil, the island’s official name actually has nothing to do with snakes. At one point in its history, people tried to clear the land using fire to create a banana plantation. However, they quickly discovered the island’s resident snakes, which made it impossible for humans to live there.

The nickname “Snake Island” comes from its most well-known inhabitants: the snakes. This small, 106-acre island has no humans living there, but there are plenty of unique plants and animals — including the golden lancehead snake (Bothrops insularis), a venomous species found nowhere else on Earth. Some have said there is a snake every 10 square feet, suggesting hundreds of thousands on the island. However, more recent studies suggest there are more like 2,400 to 2,900 snakes, which would be closer to one snake every 1,080 square feet.

Regardless of the exact numbers, the presence of even one golden lancehead snake is enough to make anyone think twice about visiting this perilous island.

Snake Island’s Golden Lancehead

Snake Island is the only place on Earth where you can find the golden lancehead snake. Scientists believe this snake evolved from the jararaca viper (Bothrops jararaca), a dangerous pit viper still found in mainland Brazil. Around 11,000 years ago, rising sea levels trapped a group of these vipers on what is now Snake Island.

Cut off from the mainland, the snakes had to adapt to their new environment. Unlike the reptiles and rodents of the mainland, Snake Island offered few food options. As a result, the golden lanceheads learned to hunt two specific types of birds on the island. Over time, natural selection led to changes in their bodies: they became better suited for moving through trees, and their venom became much stronger and more potent. The deadlier venom wasn’t for larger prey, but to quickly kill birds that were otherwise too fast to catch.

Interestingly, the golden lancehead snake specifically targets only two slower migratory bird species: the Chilean elaenia (Elaenia chilensis) in the spring and the yellow-legged thrush (Turdus flavipes) in the fall. The other resident bird species on the island are simply too fast for the snakes to hunt.

Just How Dangerous Is the Golden Lancehead Snake?

The venom of the golden lancehead snake has evolved to be extremely effective, at least five times stronger than that of its ancestors. This venom is hemotoxic, meaning it attacks red blood cells. It can destroy tissue, cause severe internal bleeding, and lead to brain hemorrhaging. A human bitten by one of these snakes, especially so far from medical help, would be in serious danger. Despite this, however, there are very few records of humans being bitten by golden lanceheads, and no reported deaths. In addition, scientists who have visited the island say the snakes are generally not aggressive.

However, the golden lancehead’s rarity and potent venom have made it a target for illegal pet traders, who can sell a single snake for as much as $30,000 on the black market. Sadly, this poaching has hurt the snakes’ naturally small population, and because Snake Island is their only habitat, they are now critically endangered.

In contrast, scientists are also very interested in these snakes for another reason. Their rarity and unique evolutionary path are fascinating, but so is the potential of their deadly venom. Venom from related snake species has shown promise in developing pharmaceutical drugs, including potential treatments for cancer. Venom from the jararaca snake is already used in blood pressure medications, so the venom of the golden lancehead might hold even more medical secrets.

Can You Visit Snake Island?

No, the public is not allowed to visit Snake Island. The Brazilian government has closed the island to protect both humans and the endangered golden lanceheads. There is a lighthouse on the island, but today it is remotely operated, with the Brazilian Navy occasionally stopping in to make repairs. In select cases, scientists and researchers are granted access to the island for study, but even then, they must be extremely careful.