Crocodiles are one of the few animals that will use any opportunity to take humans as prey. One simple rule is, bigger they are, the more dangerous they are – anything over 6ft (2m) is considered a threat to humans. Of all species, the undisputed heavyweight in terms of size is the saltwater crocodile of S.E. Asia and Australia. Reaching up to around 20ft (6.5m) in length and with the strongest measured bite of any creature these crocs are responsible for numerous deadly attacks each year. However, it is the Nile crocodile of Africa which is responsible for the highest death toll. Estimates put the number of deaths attributed to Nile crocodiles at between 150 and 500 per year making them the number one cause of death involving wildlife in Africa. This is partly due to the fact Nile crocodiles often live in close proximity to humans, but it also has a lot to do with their enormous size and deadly jaws.