According to the name of the television show that he was most known for, Australian Steve Irwin was a crocodile hunter. The nickname was good for attracting the attention of the public towards his work, but it wasn't a truly accurate description of what he did. Irwin was a marine biologist and conservation expert who just happened to have a particular affinity for crocodiles.
Given his habit of taking apparent risks with the animals - including sticking his head between their jaws to demonstrate that they wouldn't attack him - it wouldn't have been too big a surprise if he'd met his end that way. Instead, though, he was stung through the heart by a poisonous jellyfish while swimming in September 2006, a mere two days after this photograph was taken. He'd been trying to film the jellyfish swimming for a documentary he was working on at the time.