Killer Whale Violently Kills Trainer

This story has captured my attention. Maybe it is the majesty of the animal, as portrayed in Free Willy. Maybe it is that Dawn Branceau was a 40-something gal with a long-hair ponytail, like myself.
For whatever reason I find myself wondering, was Dawn's death avoidable? The latest information indicates that it was. This video shows footage of Dawn and Tillikum right before the attack. It turns out she had been feeding the whale in a "Dine With Shamu" show. And then went over to frolic with him for a bit, by lying down on a "slide out", an area of the pool that was a 4"-deep shelf. At one point after the tape stops, her hair apparently drifted across Tillikum's mouth. That was when he grabbed the ponytail and took off.
The original story that she was standing by the side of the pool and Tillikum grabbed her by the waist was wrong. Although this must have been a violent attack, as her death certificate cites drowning, along with multiple traumatic injuries. I don't buy the theory that Tillikum was lonely and wanted to play with her and didn't know his own strength. He knew his strength very well. These beasts work gently with trainers day in and day out. He knew full well that thrashing her body about would injure her. But for some reason he decided to do it. Wild animals do things like that. Especially man-eaters, or man-killers, as this particular animal was. He had killed humans twice before. And, I would think, especially a large bull-male of the species, the largest in captivity. He was no child. The trainers already knew better than to swim with him. I suspect a large reason they kept him around was for their artificial insemination program. Tillikum apparently has sired 13 babies to date.
Animal behavior specialist Brian Gisi said we may never know why the killer whale decided to attack.

However, from studying the behavior of animals for years, Gisi said several things could have played a part, such as the fact that Tilikum has fathered 13 calves.
"Breeding definitely plays a role in aggression because males are continuously trying to jockey for the best position access to the best females," Gisi said.
He said Tilikum could have been picking up on tension from other whales in the group.

Time describes the attack as particularly vicious:

Tilikum did not just knock Dawn Brancheau over and drag her down to drown at the bottom of the pool. According to a source, he rose out of the water to snag Brancheau by her ponytail, yanking her into the water for two brief but shocking episodes in the pool. After grabbing her by her hair, he toyed with her underwater for two minutes as she struggled to use trainer signals to calm him down and get him to release her. He knocked her about and, according to some reports, had her by the waist, her blood spreading through the clear water, in full sight of members of the public who had been watching Tilikum with another trainer through a glass underwater window.
(See 10 infamous animal attacks on humans.)
She was still alive at the end of the first takedown after Tilikum let her go. But he watched as she tried to get to safety and then grabbed her again and held her for another minute underwater, this time apparently killing her. He then settled at the bottom of the pool, keeping her in his mouth. She apparently remained there until the staff at SeaWorld managed to beach him and move him to a separate pen. No one at SeaWorld was available to confirm reports that Brancheau's body was badly mangled.

Killer Whales are kept in areas too small for them to feel comfortable. Animals stop breeding when they are stressed by their environment. For example zoo animals rarely breed in captivity. However, the San Diego Wild Animal Park, for example, has an excellent record of natural animal breeding, and great success with the white Rhino population (no relation to modern politicians). A white Rhino in a zoo setting will not breed. Put in on the Savannah, with acres and acres to roam across, and suddenly they get in the mood. Clearly something is wrong with the Killer Whale habitat at all of these marine exhibits. I also recall reading that there are renovations going at Sea World Orlando, so the Killer Whales are being kept in an even smaller area than usual.
I saw a comment on the internet today stating that Tillikum should be euthanized. I disagree. Do we euthanize bulls for charging people foolish enough to enter their pen? Should we punish a wild animal for acting wild? Killer Whales are playful, intelligent predators. But we expect them to swim around, come quietly to the human for food, and go back to swimming in circles. ABC News reports that Tillikum will not be punished. Although they are reviewing their protocol.
Trainer Ric O'Barry, who trained the famous Flipper in the 1960s, says:

"Along with sadness of this tragic event we can't help feeling anger toward those who insist upon exhibiting these wild creatures in habitats that can drive them to violence."
O'Barry has been an ardent campaigner against marine parks such as SeaWorld since the 1970s, saying his views on an industry he helped create changed after one of the dolphins he trained for Flipper died in his arms.