Ben Fogle joins wild crocodile research dive
Scientists are risking their lives to study crocodiles' underwater behaviour.
Zoologist Adam Britton ran a week-long pilot research project in Botswana's Okavango Delta to investigate where they hide before attacking, how they detect prey and how good their vision is underwater.
Diving expert Brad Bestelink took British adventurer Ben Fogle along on some of their dives with wild crocodiles in Australia as well.
Swimming With Crocodiles is on Sunday 19 February on BBC Two at 21:00 GMT.