'Ilha da Queimada Grande', also known as Snake Island, is an island off the coast of Brazil in the Atlantic Ocean. It is administered as part of the municipality of Itanhaém in the State of São Paulo. The island is small in size and has many different types of terrain, ranging from bare rock to rainforest, and a temperate climate. It is the only home of the critically endangered, venomous Bothrops insularis (golden lancehead pit viper), which has a diet of birds.

The snakes became trapped on the island when rising sea levels covered up the land that connected it to the mainland. The ensuing selection pressure allowed the snakes to adapt to their new environment, increasing rapidly in population and rendering the island dangerous to public visitation. Queimada Grande is closed to the public in order to protect both people and the snake population; access is only available to the Brazilian Navy and selected researchers vetted by the Chico Mendes Institute for Biodiversity Conservation, the Brazilian federal conservation unit.

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