Two huge fish due to go on display in the Tennessee Aquarium's new River Giants exhibit have died.
Both fish were Beluga sturgeon, called Horace and Boris, and a post mortem has revealed that they were suffering from quite different, but serious, health issues.
The sturgeon were originally flown to the US from the former Soviet Union back in 1976.
Horace arrived at the Tennessee Aquarium when it first opened back in 1992 and Boris followed him in 2006. The fish had since reached almost 7' in length and were great favourites with guests.
Staff at the Aquarium said a post-mortem examination showed that Boris was actually a female and had been egg bound with nearly 17 pounds of roe inside her, which had become infected. She died on Saturday.
Horace died the following day from kidney failure, thought to be most likely as a result of age or chronic kidney disease.
The River Giants exhibit is set to open April 28.
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