Off the coast of Brazil, there is an incredibly dangerous and tiny island that is out of bounds for a peculiar reason. Ilha da Queimada Grande lies off the coast of Brazil in the Atlantic Ocean and covers just 43 hectares (106 acres).
It has become famous for its abundant snake population – one for every square metres – earning it the nickname of “Snake Island”. In fact, it is home to a species of viper so rare it is found nowhere else in the world. In part to protect this species, but also to protect humans from its fatal venom, tourists are completely banned, with only a select few permitted to dock.
Snake Island has a temperate climate, and its terrain varies from bare rock to rainforest.
It is the only natural home of the critically endangered, venomous golden lancehead pit viper (Bothrops insularis). The snakes became trapped on the islands thousands of years ago, following the end of the last ice age when rising sea levels disconnected the island from the mainland.
The pressure put on the species to evolve to its new environment and a huge surge in population rendered the island too dangerous for public visits.
Today, Snake Island is closed to the public for the protection of both people and snakes, with access only available to the Brazillian Navy and selected researchers who are vetted by the Chico Mendes Institute for Biodiversity Conservation, the Brazilian federal conservation unit.
Previous estimates put the snake population at around 430,000, but recent reevaluations are much lower. The first systematic study of the golden lancehead population found the number to be 2,000 to 4,000, concentrated almost entirely in the island’s rainforest area.
It is also home to a smaller population of the Sauvage’s snail-eater (Dipsas albifrons), a non-venomous snake species.
In 2023, YouTuber Lord Miles evaded Brazilian authorities and landed on Snake Island, wearing body armour to protect himself from bites.
Scientists note, however, that the venom is designed to immobilise birds, not mammals. Indeed, because of the island’s isolation, there are no documented cases of humans being bitten by golden lanceheads. The YouTuber did not encounter a single snake during his adventure.
The island also has some grassy cleared areas due to previous deforestation. This is the origin of the island’s name – the term “queimada” is Portuguese for forest fire. Locals attempted to clear land for a banana plantation on the island by burning it.
A lighthouse was constructed in 1909 to steer ships away from the island, and the last human inhabitants left the island when the lighthouse was automated.