Chester’s death is just the latest in a long string of deaths at the controversial aquarium — five cetaceans have died there in the past year and a half. Last June, Daisy the harbour porpoise died, and in November 2016, mother-and-daughter belugas Aurora and Qila died nine days apart — reportedly from a mysterious toxic substance that had been passed to them through water, food or human interference. Jack, another harbour porpoise, died in August 2016.
Helen and Chester, the aquarium’s last cetaceans, had been companions for the past two years, and are shown in videos never wandering too far away from one another. On a daily basis, the wild-born, rescued dolphins were made to perform tricks in shows together to entertain paying guests.
Helen, who is around 30 years old, was brought to the aquarium in 2005 after being found in fishing nets in Japan several years earlier; Chester was brought to the aquarium as a calf in 2014 after being found near a beach in critical condition. Both of them were unreleasable, according to the aquarium.