Granddad, the Australian lungfish believed to be the longest living fish at any aquarium in the world, was euthanized Sunday at Chicago's Shedd Aquarium.
Grandad was thought to be "somewhere in the neighborhood of 100," said Michelle Sattler, one of his keepers at the aquarium, the Sun-Times reported. Granddad was 4 feet long and weighed 25 pounds at the time of his death.
The fish had been at Chicago's iconic aquarium since the Century of Progress World's Fair in 1933. According to Shedd, Granddad and a female were fully grown when they arrived in Chicago from the Taronga Zoo and Aquarium in Sydney, Australia.
"It is incredible to know that more than 104 million guests had the opportunity to see Granddad in our care and learn about his unique species over eight decades," Bridget Coughlin, president and chief executive of Shedd, said in a statement. "(Granddad) sparked curiosity, excitement and wonder among guests of all ages."
The centenarian lungfish occupied the stacked rock habitat in Rivers Gallery of the aquarium with his mate, who died in 1980.
"In 1992, Granddad was taken off exhibit while his space was incorporated into the double Southeast Asian Streams habitat," said the Shedd statement. "During his nearly two-year hiatus in a reserve area, staff members repeatedly assured anxious aquarium members and other guests that their favorite lungfish was doing fine and would be back on view in a spacious new habitat recreating a Queensland riverbank ecosystem. The exhibit opened in May 1994 with Granddad and five 8- to 10-year-old lungfish donated by the Australian government."
Sattler told the Chicago Tribune that Granddad had been losing interest in his food over the past couple of weeks and exhibiting signs of a "shutting down" of vital systems on Saturday.
"It's a sad week for us, and it's history for a lot of people," Sattler said.
When a physical examination showed Granddad's organs were failing and his quality of life was slipping away, the health team made the "humane" decision to euthanize him, the aquarium said.
A full necropsy conducted in partnership with pathologists from the University of Illinois College of Veterinary Medicine confirmed Granddad the lungfish's age-related deterioration
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