Marine animal entertainment park SeaWorld announced this morning that beloved orca Tilikum has died. The 35-year-old whale—who SeaWorld believes died due to a persistent bacterial lung infection—was the subject of eye-opening 2013 documentary Blackfish which brought to light the mistreatment of marine animals at the park. Numerous animals, including Dart the Dolphin and Unna the orca whale, have recently succumbed to death inside SeaWorld’s tanks. People for the Ethical Treatment of Animals’ Senior Vice President Lisa Lange issued a response to Tilikum’s tragic death. “SeaWorld needs to release all the remaining animals from its parks—the orcas, beluga whales, bottlenose dolphins, sea lions, walruses, [and] the other animals who remain in SeaWorld’s tanks and exhibits,” Lange said. “Tilikum must be the last orca to die inside a SeaWorld amusement park.” While the park will still keep wild animals captive at their various locations, SeaWorld plans to hold the final “Ocean One” orca show in San Diego, CA on Sunday.