<P> Tilikum, a male killer whale, has been involved in the death of three individuals since his capture near Iceland in November 1983 . In 1991, Tilikum and two other killer whales grabbed 20 - year - old trainer Keltie Byrne in their mouths and tossed her to each other, drowning Byrne . On July 5, 1999, Daniel P. Dukes visited SeaWorld and stayed after the park closed, evading security so as to enter a killer whale tank . He was found dead the next day, floating in Tilikum's pool . He died due to a combination of hypothermia, trauma, and drowning but Dukes was covered in bruises, abrasions and bite marks, and his scrotum had been ripped open, indicating that Tilikum had toyed with the victim . It is unclear whether Tilikum actually caused the man's death . On February 24, 2010, after a noontime performance at Sea World, Orlando, Florida, Tilikum killed trainer Dawn Brancheau during a training session with the whale . This latest incident with Tilikum reawakened a heated discussion about the effect of captivity on the killer whale's behavior . In May 2012, Occupational Safety and Health Administration administrative law judge Ken Welsch faulted SeaWorld for the death of Dawn Brancheau and introduced regulations requiring a physical barrier between trainers and killer whales . </P> <P> Kasatka, a female killer whale who was captured off the coast of Iceland in October 1978 at the age of one year, has shown aggression toward humans . Kasatka tried to bite a trainer during a show in 1993, and again in 1999 . On November 30, 2006, Kasatka grabbed a trainer and dragged him underwater during their show . The trainer suffered puncture wounds to both feet and a torn metatarsal ligament in his left foot . </P> <P> On Christmas Eve of 2009, 29 - year - old Alexis Martínez of Loro Parque, Tenerife, Spain was killed by a whale named Keto . After spending two and a half minutes at the bottom of the 12 - meter - deep main pool, his body was retrieved but he could not be revived . The park initially characterized the death as an "accident" and claimed that the body showed no signs of violence, but the subsequent autopsy report stated that Martinez died due to grave injuries sustained by an orca attack, including multiple compression fractures, tears to vital organs, and the bite marks of the animal on his body . During the investigation into the death of Alexis Martinez, it came to light that the park had also mischaracterized to the public a 2007 incident with Tekoa, the other male, and claimed it was also an accident rather than an attack . </P> <P> One infamous incident of killer whale aggression took place in August 1989, when the dominant female Icelandic killer whale at SeaWorld San Diego, Kandu V, attempted to "rake" a female newcomer named Corky . Raking is a way orcas show dominance by forcefully scratching at another with their teeth . Kandu charged at Corky, attempting to rake her, missed and continued swimming into the back pool, where she ended up ramming the wall, rupturing an artery in her jaw . The crowd was quickly ushered out of the stadium . Forty - five minutes later Kandu V sank to the bottom of the pool and died . </P>

When was the last time seaworld captured a killer whale