Snake Facts

Largest snakes

Many people believe that the South American anaconda is the longest snake. There are reports of anacondas up to 36.5m long, but this has never been proved. US President Theodore Roosevelt once offered $5,000 to anyone who could produce the skin or vertebrae of an anaconda of more than 9m long. The US Wildlife Conservation Society increased this offer to $50,000, but the prize has never been claimed. The reticulated or royal python is probably the longest snake at up to 10.7m, but the anaconda may be the heaviest at up to 230kg

Smallest snake

The thread snake is rarely longer than 108mm. The spotted dwarf adder is the smallest venomous snake at 22.8cm long.

Deadliest snakes

The coastal taipan of Australia injects the most venom per bite with 120mg. Since just 1mg is enough to kill a person, the venom from a single bite could kill 120 people. The common krait venom is even more dangerous - only 0.5mg can be fatal.

The fast-moving black mamba of central and southern Africa kills 90 to 100 per cent of the people it bites. Up to 3,000 people a year die from snakebites in India and 1,000 in Sri Lanka, where Russell's viper is the most likely cause. This snake once killed as many as 50,000 people a year, but there have been fewer deaths since antivenin (the antidote to snake venom) became more widely available.