An investigation is underway to determine the cause of death of five stingrays at Gladys Porter Zoo in Brownsville, according to a news release.

The stingrays were found dead Monday at the zoo’s Russell Aquatic Ecology Center. 

All life support systems and the pump and filtration system at the center were fully operational, and a necropsy conducted on the stingrays showed they were all in “good body condition,” the release stated.

“As is routine for diagnosing the cause of animal death, tissue samples will be sent to a veterinary diagnostic lab for further evaluation,” the release stated.

On January 2022, a group of stingrays was killed after the system that provides oxygen and filtration to the tanks failed.

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