Kasatka was 42-years-old and had a lung disease. Photo / Getty
By Jessica Finn, with AP
One of the last killer whales caught in captivity for SeaWorld was euthanised in San Diego, making her the second orca death at the marine parks in a month.
The whale named Kasatka was put down Tuesday evening after battling a lung disease for years.
SeaWorld says Kasatka was "surrounded by members of her pod, as well as the veterinarians and caretakers who loved her," when she died, the Daily Mail reports.
Her death comes less than a month after a three-month-old killer whale born in captivity under SeaWorld's former orca-breeding program died at the company's San Antonio park after suffering from pneumonia.
She was one of the entertainment company's last killer whales to come from the wild. Katsatka is now the third orca death this year at one of SeaWorld's marine parks.
Veterinarians made the difficult decision to euthanise Kasatka after her health started to decline in recent days despite treatment, which included a custom-built inhaler that allowed the medicine to go directly to her lungs.
She was estimated to be 42 years old - SeaWorld's second-oldest orca after Corky, which is believed to be 53.
Kristi Burtis, an orca behaviorist, spent years working with Kasatka.
"Although I am heartbroken, I am grateful for the special time we had together and for the difference she has made for wild orcas by all that we have learned from her," Burtis said in a statement.
"I adored Kasatka and loved sharing her with millions of people. I will miss her very much."
SeaWorld has not collected a wild orca in nearly 40 years, and most of its orcas were born in captivity. Kasatka was captured near Iceland in 1978.
SeaWorld announced the end of its breeding program in March 2016, following years of pressure from animal rights protests and shifting public opinion about orcas being held in captivity.
Tilikum, which sired 14 calves over nearly 25 years in Orlando, died of bacterial pneumonia in January.
Tilikum killed trainer Dawn Brancheau in Orlando in 2010 by dragging her into the pool before shocked visitors after a 'Dine with Shamu' show.
Following the trainer's death, criticism of the company intensified with the 2013 release of "Blackfish", a documentary critical of SeaWorld's orca care that focused on Tilikum.
Since then, SeaWorld has decided to phase out its world-famous killer whale performances by 2019.
SeaWorld has 21 orcas left in the US.
The youngest, Amaya, was born in December 2014. All the orcas are expected to remain on display and available for researchers for years to come in Orlando, San Diego and San Antonio.
The local group of the People for the Ethical Treatment of Animals planned to hold a gathering near the San Diego park Wednesday as a memorial to Kasatka.
The group is calling for the company to release all of SeaWorld's orcas to sea pens or coastal sanctuaries.
"The abusement park didn't even respect this orca enough to give her a good-quality life, and it needs to send the remaining marine mammals to seaside sanctuaries before they follow Kasatka and the 40 orcas before her to the grave," PETA Senior Vice President Tracy Reiman said in a statement.
The Animal Legal Defense Fund says SeaWorld worked to conceal Kasatka's declining health for years before ultimately euthanising her.
"SeaWorld ... was desperate to avoid critical press coverage," according to a release from the ALDF.
"SeaWorld has released a memorial video for Kasatka, calling her 'the matriarch,' a sad reminder of the life Kasatka should have had. Had Kasatka not been taken from her ocean home in 1978, she would have enjoyed life as a true matriarch, living with her calves in a tight knit family."
"Instead," the ADLF says, "her first born was sent to another facility after only a few years together, and her physically and emotionally stressful life in captivity damaged her so severely she was consistently observed unable to care for her most recent calf."