SeaWorld San Diego is mourning the loss of Nakai, an Orca born at the park in 2001.
The park announced Nakai's death in a Facebook post on Friday. Nakai passed away Thursday night due to an infection, the park said.
"Every attempt was made to save his life. Veterinarians and health specialists had been actively treating an infection, but aggressive therapeutic and diagnostic efforts were unsuccessful," the park's Facebook post read in part.
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Nakai is remembered for his curiosity and ability to learn quickly, according to the post. He participated in hearing studies that helped scientists understand how noise from ships and humans impacted his species.
A SeaWorld staffer who helped take care of Nakai for nearly the whale's entire life said, “I have been professionally and personally invested in the welfare of Nakai since he was born in our park, and the bond we shared was very strong. He was very friendly and an overall playful guy who loved to interact with people. It was a joy to care for and learn from him and I will miss him greatly. He was a huge part of my life and of our family here at SeaWorld San Diego. We appreciate the support of the community as we grieve his loss together with his loyal fans everywhere.”