An Australian lungfish that entranced visitors to Chicago's Shedd Aquarium for more than 80 years has been euthanized due to old age, the popular tourist attraction announced Monday. Granddad, who was 4ft long and weighed 25lb, had stopped eating and started showing signs of organ failure. He was euthanized on Sunday. A necropsy - or animal autopsy - found conditions consistent with old age, aquarium officials said. 'For a fish who spent much of his time imitating a fallen log, he sparked curiosity, excitement and wonder among guests of all ages who would hear his story,' said Bridget C. Coughlin, Shedd Aquarium's president and CEO. A Shedd spokesman said Granddad's exact age was unknown but that he was believed to be in his mid-90s. The aquarium acquired him from the Sydney Aquarium in Australia during a 1933 collecting expedition in preparation for the 1933-34 Chicago World's Fair. Granddad was one of two lungfish that attracted visitors during that year's A Century of Progress International Exposition in Chicago. Aquarium officials estimate more than 104 million people saw Granddad over eight decades. Rob Vernon, a spokesman for the Association of Zoos and Aquariums, said the nonprofit group is unaware of any older fish kept by a zoo or aquarium that it accredits in the United States or eight other countries. 'Granddad lived a pretty relaxed life, enjoyed interactions with us, including gentle pats along his back, and loved to eat his leafy greens,' said Michelle Sattler, who was Granddad's caretaker for more than 30 years. Lungfish, which are native to the Mary and Burnett rivers in Queensland, Australia, can live up to 100 years and are a protected species in Australia. The lungfish has a single primitive lung and are among the few fish that can breathe air. The species has existed for more than 380million years and has not changed for 100million years, according to the aquarium. The fish was euthanized with an overdose quantity of anesthetic that was added to his tank.
