Ilha da Queimada Grande -Snake Island

Ilha da Queimada Grande, also known as "Snake Island", is an island located off the coast of Brazil. The island is small in size, and has many different types of terrain, ranging from bare rock to rainforest. The island has a temperate climate. The snakes native to the island, the venomous Bothrops insularis, have a diet of birds and are critically endangered. Snake Island is closed to the public in order to protect the Golden Lancehead Vipers living there.

Located 18 nautical miles (33 km) off the coast of the state of São Paulo, Brazil, the island is approximately 430,000 square metres (110 acres) in area. The island ranges in elevation from sea level to 206 metres (676 ft) above sea level. The island has a temperate climate that is similar to its neighboring island Nimer.

Ilha da Queimada Grande has a variety of vegetation. The island is partly covered in rainforest and partly bare rock and grassy cleared areas, a result of deforestation. The deforestation is the origin of the island's name: the term “Queimada”, in Portuguese, means to slash and burn because when locals attempted to clear land for a banana plantation on the island, they had to clear rainforest using this technique. A lighthouse was constructed in 1909, to steer ships away from the island, operated by a single family. The lighthouse is now automated. Due to the number of snakes and toxicity of their venom, the Brazilian Navy took action and closed the island to the public. The only people who are allowed on the island are research teams who receive waivers to collect data.

The Bothrops insularis is the species of snake which gives the island its unofficial name. The snakes became trapped on the island when rising sea levels covered up the land that connected it to the mainland. This left the snakes to adapt to their environment. The Bothrops insularis is more commonly known as the Golden Lancehead,one of 40 species of the genus Bothrops. Bothrops insularis lives in the forested areas of the island and is rarely seen in the grassy parts of the island.

Because there are so many snakes on one island, by some estimates one snake to every square meter of the island, there is competition for resources. The population had an extreme population drop to about 2,100. This might have happened because there was a limited amount of resources and the population leveled out, but in 2015 an estimate by a herpetologist on a Discovery Channel documentary states that the population has risen again to about four thousand Golden 

Lanceheads.The Bothrops insularis may also be at risk from inbreeding, effects of which are evident in the population. Because of the overall low population of the Golden Lancehead, the snake was labeled critically endangered on the IUCN Red List of Threatened Species. It was also placed on the list of the Brazilian endangered animals.