• Where is Ilha de Queimada Grande located?
  • Why is access to Snake Island prohibited?
    • Access to the island is prohibited by the Brazilian government due to the extreme danger posed by the 2,000 to 4,000 venomous snakes that inhabit the island.
  • What species of snake is most common on the island?
    • The island’s main inhabitant is the golden lancehead pit viper, an endangered species that thrives on this isolated strip of land where there are few predators.
  • How did the golden lancehead evolve?
    • The golden lancehead evolved from the jararaca pit viper and developed a much more potent venom than its mainland relatives.
  • Why is the golden lancehead's venom so dangerous?
    • The golden lancehead has venom that can kill a human in less than 1 hour by causing kidney failure, brain hemorrhaging, necrosis of muscular tissue, and intestinal bleeding.
  • Is the golden lancehead endangered?
  • What is the climate and terrain like on Snake Island?
    • The island has a temperate climate with temperatures between 65°F and 80°F year-round. The terrain includes bare rock, open grasslands, and rainforest, and parts of the island rise approximately 700 feet above sea level.
  • How did the snakes come to inhabit Ilha de Queimada Grande?
    • Local lore suggests that pirates placed the snakes on the island to protect their gold. However, scientists believe the snakes evolved naturally over the past 11,000 years after the island became isolated from mainland Brazil due to rising sea levels.
  • Why did the golden lancehead evolve such deadly venom?
    • With no natural predators, the snakes proliferated and adapted to prey on migratory birds. The evolution of their potent venom helped them kill prey quickly, preventing birds from escaping after being bitten.
  • How do golden lancehead snakes hunt their prey?
    • Since they cannot track their prey over long distances, the golden lancehead developed an extremely fast-acting venom. Unlike many other vipers, they keep their prey in their mouths after biting instead of releasing them.
  • What is the origin of the island's name?
    • The name Queimada means to slash and burn. The island was deforested in the early 20th century to be used as a banana plantation, which contributed to the loss of snake habitat.
  • Did people ever live on Snake Island?
    • Lighthouse keepers and their families lived on the island from 1909 until the 1920s. However, they eventually abandoned the island due to the deadly snake population.
  • Why was the island closed to the public?
    • In the 1920s, a lighthouse keeper and his family were killed by the venomous snakes. After the incident, the Brazilian Navy closed the island to the public and automated the lighthouse.
  • How is deforestation affecting the golden lancehead population?
    • Despite being protected, the golden lancehead's habitat continues to shrink due to deforestation by the navy and a reduction of the island's rainforest.
  • Why is Snake Island off-limits to tourists?
    • The island is off-limits to tourists due to an ordinance from the Brazilian government. Any authorized trips must be accompanied by a doctor due to the danger posed by the snakes.
  • Who is allowed to visit Snake Island?
    • The Brazilian Navy visits annually to maintain the lighthouse, which has been automated since the 1920s. Scientists and researchers from the Chico Mendes Institute for Biodiversity Conservation may also visit for research, but they must be vetted by the government before access is granted.
  • How dangerous is the golden lancehead viper?
    • The golden lancehead is a close relative of the lancehead viper, the species responsible for 90% of snakebite deaths in Brazil.
  • How do wildlife smugglers impact Snake Island?
    • Despite the ban on travel, wildlife smugglers illegally capture the snakes for sale on the black market. A single golden lancehead viper can sell for as much as $30,000 to collectors and certain researchers.
  • Why is the golden lancehead viper endangered?
    • The species is now considered endangered due to habitat degradation, inbreeding, and disease. The illegal wildlife trade has further contributed to its decline.

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