Australian animal show host Steve Irwin, otherwise known as the "Crocodile Hunter," was killed today while filming a new documentary. He was 44.

He was diving off the coast of the Great Barrier Reef in his home country on Monday (Sept 4), when the accident occurred. At first authorities refused to identify the diver, only saying that he had been killed by a stingray. It was only after the family was notified that it was revealed the diver was Irwin.

The famous and sometimes controversial tv personality had been filming an underwater scene for his upcoming documentary on the reef near Low Isles Reef, about 1200 miles north of the city of Brisbane.

Authorities speculate that the cause of death was stingray strike to the chest. Experts in Australia say that for that to happen, the victim had to be stung close to the heart and also have a reaction to the sting, as stingray barbs are very strong and release poison if touched. They also think that for a stingray to attack in such a manner, it would have had to be startled or felt threatened, and it's possible that while filming, Irwin might have provoked the creature with his normal hands-on approach to touching and grabbing animals on camera.

Though Irwin had courted controversy several times during his career, including a January 2004 incident where he took his 1-month-old son into a crocodile pen during a wildlife show, he was very much a vocal champion for the rights of animals. Ever since his show, "Crocodile Hunter," first aired on Australian television in 1992, Irwin had advocated the conservation of animals and hoped to used his show and fame as a platform with which to educate the public about the beauty of all life on this planet.

Irwin is survived by his wife Terri, and their children, daughter Bindi Sue, 8, and son Bob, now 2.

For more information on Steve Irwin, please visit the Australian Zoo website or the Discovery Channel website.

More on the passing of Steve Irwin on BellaOnline.com:

Friends and Family of Steve Irwin Respond to His Accidental Death

Remembering Steve Irwin

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