Why did whale drown his trainer at theme park?

Miami: Homicide investigators in Orlando said on Thursday that the death of a trainer at SeaWorld on Wednesday occurred when the theme park's largest male Orca whale grabbed the trainer by her hair while she stood in shallow water, and dragged her into a deep pool on Wednesday.

Within minutes, the trainer, Dawn Brancheau, 40, was dead from drowning and what the police described as "multiple traumatic injuries." There were no signs of foul play on the part of anyone other than the whale, but questions about the mammal's intent continued to linger.

Was the 12,000-pound Orca, Tilikum (Tilly for short) acting violently, possibly because of stress from captivity? Or was he just playing?

When chimpanzees, alligators, pythons and pit bulls have been involved in attacks against humans, they have generally been euthanized quickly, without much debate. But whales and other large mammals in captivity are different, experts say, because they are truly wild, and they live under the watchful care of professional trainers, who can explain their behavior in context.

Tilly, more than most, has been hard to defend. His record is hardly clean. In 1991, he and two female killer whales drowned a trainer, Keltie Byrne, at an aquarium in Canada before a crowd of spectators. Eight years later, SeaWorld officials found the naked, lifeless body of a homeless man who had sneaked into Tilly's pool after hours lying across the whale's back.

At least one animal activist, Russ Rector, a Fort Lauderdale dolphin trainer, said he wrote a letter to SeaWorld three years ago warning that the park's trainers were inviting attacks by pushing show mammals too hard to please a crowd. Video of Tilly taken before the drowning on Wednesday shows that he was excited, or agitated, depending on one's point of view.

Richard Ellis, a marine conservationist at the American Museum of Natural History in New York, said that generally whales like Tilly which are actually members of the dolphin family - are too smart to have been acting purely out of impulse. Pulling Brancheau into the water, he said, was not an accident.

"This was not an insane, uncontrollable act," Ellis told The Associated Press. "This was premeditated."

But was it intentionally violent? Graham Worthy, a whale expert at the University of Central Florida, said he doubted it. "These are animals that can tear apart a blue whale," Worthy said. "If this was an animal that was trying to be aggressive, what would have happened would be much more gruesome."

He said that in a handful of his own interactions with Tilly, "He struck me as a laid-back guy who is kind of lazy, frankly. He's a misunderstood big kid."

Sea World's head of animal training, Chuck Tompkins, said in an interview that Tilly and all of SeaWorld's whales were closely monitored and were not put on display if they showed signs of abnormal behavior. He denied that trainers had pushed the animals too hard, or that Tilly bore any responsibility for his actions.

"They are not overworked," he said. "They are not stressed out."

He said that SeaWorld would not even consider euthanizing Tilly. "He is a member of a family group here, a pod of animals," Tompkins said, adding, "These animals are a valuable resource for us to learn from."

But Tilly's ultimate value may lie in his being more than just an educator. He is SeaWorld's largest, oldest male and he has sired 14 calves - making him the park's top stud. So in biological and economic terms Tilly is essentially one of the animal kingdom's most valuable defendants. "SeaWorld is a for-profit organization," said Nancy Black, a marine biologist with Monterey Bay Whale Watch in Monterey, Calif. "That's a big money-making animal."