SeaWorld Curator: Trainer Dawn Brancheau's Ponytail Likely Caused ...The casual swing of a ponytail was likely what caused a killer whale in Orlando's SeaWorld to attack and drown an experienced trainer before the terrified eyes of dozens of bystanders, a SeaWorld official said today."What we have found out is that Dawn [Brancheau] had just finished up a very good session with this animal. ... She was interacting with him, petting him on the nose," Chuck Tompkins, curator of zoological operations at SeaWorld Orlando, told "Good Morning America." "Dawn had very long hair in a ponytail. That ponytail had swung in front of him. He grabbed her by the hair and pulled her underwater and held her underwater."

Eyewitnesses could see clearly through the viewing glass as the 12,000 pound killer whale named Tillikum thrashed Brancheau viciously underwater.

"We thought it was part of the act," said tourist Wayne Gillespie, who was at the killer whale show with his wife and two children. "We thought maybe they were playing together until we realized he was thrashing around pretty hard. That's how we knew something was wrong."

Within minutes the Shamu Stadium, where the killer whale show takes place, was evacuated. Brancheau was pronounced dead at the scene, Orange County Sheriff's homicide investigators said Wednesday.

Though it's the third time Tillikum has been involved in a person's death, there are reportedly no plans to take the massive animal out of the show.

"We need to evaluate how to do this the right way," Tompkins said. "We need to evaluate our handling procedures and how we interact with him. ... I can guarantee we will make any change necessary.

"He's a good animal," he said.

Brancheau spent 16 years of her life working with killer whales, and Tompkins said she was one of the best.

"We're a small team of people here. We work very closely together," Tompkins said. "It's a huge loss."

Tillikum, a male or bull whale, has lived at the park since 1992, and is one of eight killer whales there.

Dan Brown, vice president and general manager of SeaWorld Orlando, said Brancheau was one of the park's "most experienced trainers."

"It is with great sadness that I report that one of our most experienced animal trainers drowned in an incident with one of our killer whales this afternoon," said Brown Wednesday.

"We have never, in the history of our parks, experienced an incident like this," he said.

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