Snake Island, located off the coast of Brazil, is a unique place on Earth where critically endangered yellow-headed cobras can be found. The island is home to thousands of venomous snakes, with some reaching lengths of up to 1.2 meters. Due to the toxic nature of the snakes, the Brazilian navy has prohibited people from visiting the island since the 1920s.
The island, which is about 34 km off the southeastern coast of Brazil, has an area of 43 hectares, covered mostly by rainforest. The remaining land consists of barren areas and rocky beaches. Snake Island was once connected to the mainland, but rising sea levels submerged the viaduct about 10,000 years ago, isolating a population of yellow-headed cobras on the island. Without any natural predators on the island, the snakes have adapted and multiplied.
The venom of the yellow-headed cobra is highly potent and has evolved to quickly kill their prey, which includes migrating birds and other species on the island. The venom is five times more powerful than their close relative, the Bothrops jararaca, that lives on the mainland. The snakes use their venom for hunting rather than self-defense, making them extremely dangerous to humans as well.
Despite the danger posed by these snakes, some brave individuals continued living on Snake Island until 1920 to operate a lighthouse that was built in 1909. Researchers estimate that there are between 2,000 to 4,000 yellow-headed cobras living on
