Trainer Dawn Brancheau feeds Tilikum on Feb. 24 before the whale pulls her into the water and kills her at SeaWorld in Orlando.
Wild animals at the nation's sea mammal and animal parks, such as SeaWorld, Busch Gardens and Six Flags, have killed three people in the past decade and injured at least 16, according to a USA TODAY review.
SeaWorld and other animal parks say such incidents are rare, but safety experts say "near misses," which may go unreported, also signal a potential for more tragedy.
"We often learn from near misses," Assistant Labor Secretary David Michaels said. He said animal parks should investigate such incidents to identify hazards and alter procedures. The review did not include zoos and circuses.
Most trainer injuries are not reviewed by federal or state workplace safety authorities. The standards for triggering an investigation are high, including hospital stays exceeding 24 hours, limb amputation or injury of three or more employees.
IN-DEPTH: List of captive animal attacks since 2000
PICTURES: Killer whale immediately after Sea World attack
Three of the 23 killer whales in captivity in the U.S. have been involved in multiple incidents, all at SeaWorld. SeaWorld has 21 killer whales, four on loan to a park in Spain's Canary Islands and one on loan to a park in Canada. The killer whale Tilikum, implicated in two deaths in 1991 and 1999, drowned orca trainer Dawn Brancheau, 40, at SeaWorld Orlando in February.
SeaWorld Parks corporate curator Chuck Tompkins said the company is conducting an "unprecedented review" of Brancheau's death that includes examining previous incidents. Trainers are keeping a safe distance from Tilikum's mouth, and the animal is not performing, he said.
Pictures: Killer whale immediately after Sea World attack
The 1991 incident, in which Tilikum and two other orcas drowned a trainer, occurred before Tilikum came to SeaWorld, Tompkins said. In 1999, a homeless man was found drowned in Tilikum's tank, he said. USA TODAY also provided SeaWorld a list of incidents in its parks in the past decade; Tompkins declined to discuss those in detail.
"Out of the 46 years we've been doing this, this is the first time we've had a fatality" involving a trainer, he said. In more than 2 million "interactions" with the park's killer whales since 1988, trainers have had "less than 10 of those major incidents," he said. "The potential of danger is always there. You still have the variable of the animal, no matter how safe you try to make an environment."
The Association of Zoos and Aquariums, which accredits SeaWorld, asked it to submit a report on Brancheau's death, spokesman Steve Feldman said.
In addition to the U.S. incidents, Keto, a killer whale on loan from SeaWorld, drowned trainer Alexis Martinez, 29, at the Canary Islands park in December, the park said in a statement. The trainer was practicing with Keto for a Christmas show.
Here are links to all of our coverage of the SeaWorld Orlando attack:
Donna Leinwand, USA TODAY