Irwin's public image was dented, however, in 2004 when he caused an uproar by holding his infant son in one arm while feeding large crocodiles inside a zoo pen. Irwin claimed at the time there was no danger to the child, and authorities declined to charge Irwin with violating safety regulations.
Later that year, he was accused of getting too close to penguins, a seal and humpback whales in Antarctica while making a documentary. Irwin denied any wrongdoing, and an Australian Environment Department investigation recommended no action be taken against him.
Stingrays have a serrated, toxin-loaded barb, or spine, on the top of their tail. The barb, which can be up to 10 inches long, flexes if a ray is frightened. Stings usually occur to people when they step on or swim too close to a ray and can be excruciatingly painful but are rarely fatal, said University of Queensland marine neuroscientist Shaun Collin.
Collin said he suspected Irwin died because the barb pierced under his ribcage and directly into his heart.
"It was extraordinarily bad luck. It's not easy to get spined by a stingray and to be killed by one is very rare," Collin said.
News of Irwin's death spread quickly, and tributes flowed from all quarters of society.
At Australia Zoo at Beerwah, south Queensland, floral tributes were dropped at the entrance, where a huge fake crocodile gapes. Drivers honked their horns as they passed.
"Steve, from all God's creatures, thank you. Rest in peace," was written on a card with a bouquet of native flowers.
"We're all very shocked. I don't know what the zoo will do without him. He's done so much for us, the environment and it's a big loss," said Paula Kelly, a local resident and volunteer at the zoo, after dropping off a wreath at the gate.
Stainton said Irwin's American-born wife Terri, from Eugene, Ore., had been informed of his death, and had told their daughter Bindi Sue, 8, and son Bob, who will turn 3 in December.
The couple met when she went on vacation in Australia in 1991 and visited Irwin's Australia Zoo; they were married six months later. Sometimes referred to as the "Crocodile Huntress," she costarred on her husband's television show and in his 2002 movie.
