The matriarch of SeaWorld's orca family died at 42 years old on Tuesday night after a years-long battle with a lung disease, the park announced.

Caretakers made the decision to euthanize Kasatka to prevent her quality of life from eroding further after her health and appetite declined significantly over the past several days, SeaWorld said. She died at about 8:15 p.m., surrounded by caretakers and members of her pod, the park added.

"Today, I lost a member of my family," orca behaviorist Kristi Burtis said in a statement. "I have spent the past several years with Kasatka and was truly blessed to be part of her life. 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."

Kasatka, who was captured off the coast of Iceland in 1978, became the mother of four orcas, grandmother of six, and great-grandmother of two. Only the female orca Corky, also in San Diego, is believed to be older at an estimated 53 years old.

Kasatka made international headlines in 2006 when she grabbed her trainer during a show and dragged him underwater, breaking his foot. At one point, she held him to the bottom of the pool for less than a minute before resurfacing, where he was eventually rescued and hospitalized.

