Archive · 3 Oct 2025
Deadly Snake Islands: Threats to Humans and Species
Some islands are home to very dangerous snakes.
One, called Snake Island in Brazil, has Golden Lancehead Vipers, which are extremely venomous.
These snakes are found nowhere else.
Another island, Shedao Island in China, has Shedao Pit Vipers.
These snakes also have strong venom to hunt the birds that migrate there.
Snake Island’s snakes are endangered because of their low numbers, and access is restricted to protect them and people.
Shedao Pit Vipers are listed as a vulnerable species.
Brazil's Snake Island is home to the Golden Lancehead Vipers.
Golden Lanceheads are critically endangered and only found on that island.
The snake's venom is dangerous, destroying blood cells and causing organ failure.
Shedao Island, China, is home to many venomous pit vipers.
The Shedao Pit Viper is considered a vulnerable species.
- Who
- The focus is on Golden Lancehead Vipers (Brazil) and Shedao Pit Vipers (China).
- What
- Two islands, Brazil's Snake Island and China's Shedao Island, are home to deadly venomous snakes.
- When
- The snakes became isolated after rising sea levels following the last ice age. Shedao Pit Vipers were listed as vulnerable in 2011.
- Where
- Ilha da Queimada Grande (Snake Island) off Brazil and Shedao Island off the coast of China.
- Why
- Snakes evolved strong venom. The public is banned from Snake Island to protect both people and the snakes.
- Snake Island (Brazil) Snakes
- Golden Lancehead Vipers
- Snake Island (China) Snakes
- Shedao Pit Vipers
- Golden Lancehead Population
- Approximately 2,400-2,900
- Shedao Island Size
- 73 hectares (180 acres)
- Shedao Pit Viper Threats
- Listed as Vulnerable in 2011