SeaWorld has announced the death of Tilikum, an orca that had been under the company's care for 25 years and whose life had been explored in the documentary Blackfish.
"Tilikum passed away early this morning, January 6, surrounded by the trainers, care staff and veterinarians that provided him around-the-clock world-class care," the company said in a statement.
The famous killer whale was estimated to be 36 years old and had been sick for some time, with SeaWorld warning in March 2016 that his health was deteriorating.
The film Blackfish was critical of Tilikum's quality of life under SeaWorld's care, as the animal became a focal point in efforts by activists to shed light on what they thought was unfair treatment.
SeaWorld, in its statement, did not directly address the controversies surrounding Tilikum, instead offering: "While today is a difficult day for the SeaWorld family, it's important to remember that Tilikum lived a long and enriching life while at SeaWorld and inspired millions of people to care about this amazing species."
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Tilikum was also known for having killed trainer Dawn Brancheau in 2010 during a live show.
"Tilikum's life will always be inextricably connected with the loss of our dear friend and colleague, Dawn Brancheau," Sea World said. "While we all experienced profound sadness about that loss, we continued to offer Tilikum the best care possible, each and every day, from the country's leading experts in marine mammals."
In November 2015, the company announced it would end its killer whale shows, and in March 2016 it said it would no longer breed orcas. Following Tilikum's death, SeaWorld is now home to 22 orcas among its facilities in Orlando, San Antonio and San Diego.
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