Kiska, best known as the "world’s loneliest" orca, has sadly passed away at Marineland in Ontario, Canada.
According to TMZ, Marineland announced the 47-year-old female whale's death in a statement, writing: "Marineland’s marine mammal care team and experts did everything possible to support Kiska’s comfort and will mourn her loss."
Brent Ross, a spokesperson of the Canadian province's solicitor general ministry, stated that "a necropsy was conducted by professionals retained by Marineland," as cited by People.
Although officials have not yet disclosed her cause of death, the themed zoo and amusement park told St. Catharine’s Standard that her health had been declining for weeks.
Kiska was first captured in Icelandic waters back in 1979, alongside the orca Keiko - who was featured in the film Free Willy - and was moved to Marineland to live out her life, per The New York Post.
People for the Ethical Treatment of Animals (PETA) eventually dubbed Kiska as the "world's loneliest orca" because they are understood to be "extremely social animals," according to the National Wildlife Federation.
She lived at different aquariums before ending up in Niagara Falls and gave birth to five calves, all of which died at young ages. She was then left to live alone in her tank.
In 2019, Canada passed a bill to end the confinement of whales and dolphins, however, the park was able to keep Kiska due to a grandfather clause that granted them an exemption.
Despite the exemption, PETA and numerous other animal rights organizations campaigned for the orca's release for years as she lived in a cramped tank and shared tribute statements mourning her death.
"She spent her final years floating listlessly or banging her head against the tank's walls," PETA wrote on Twitter, referencing footage taken by animal activist Phil Demers of Kiska in her cramped tank. "She deserved to stay in the ocean with her family."
"Rest in peace, Kiska You're free now," PETA added in a separate tweet.
The World Animal Protection US also took their Twitter to shed light on Kiska's tragic detainment in the last few years of her life and penned: "She has been filmed floating lifelessly in her tank, swimming in endless circles, or forcefully bashing her head into the sides of her tank."
"To honor her memory & the memories of all the orcas who have died in captivity, we will continue our fight to end cetacean entertainment," the organization added.
Rest in peace, Kiska.