TAMPA — Soon after the ZooTampa at Lowry Park opened Thursday morning, staff members noticed the stingrays were acting strangely.
Word spread to the animal care and veterinary teams, who rushed to check on them, said Dr. Cynthia Stringfield, senior vice president of animal health, conservation and education.
It was too late. Within an hour, all 12 residents of the beloved Stingray Bay exhibit were dead.
By Friday afternoon, she said, an internal investigation into the equipment and water quality yielded no clues as to what caused their sudden, mysterious deaths. Zoo officials are searching for answers.
“We are emotionally exhausted,” Stringfield said. “(Thursday) was just a horrible day. It’s like a day out of your nightmare, pretty much ... We’re really focused on trying to get to the bottom of what happened.”
She said there is no indication of foul play and that law enforcement is not involved in the investigation.
The stingrays were housed in a 16,000-gallon saltwater touch tank known as Stingray Bay, which the zoo said will be closed for at least eight weeks while officials conduct an investigation.
The exhibit has been open since 2001 and is hugely popular because zoo patrons have direct access to the creatures, Stringfield said. They could buy shrimp and watch as the rays sucked it off their hands, or even touch one if it was feeling friendly enough toward its human observers.
Among the dead were seven cownose stingrays, four Southern stingrays and one Atlantic stingray.
The staff is investigating the tank’s mechanical components but already determined the water’s “temperature, quality, oxygen and Ph levels” were at “optimal water quality and conditions,” ZooTampa said in a statement issued Friday.
“The Zoo is looking into every possibility to uncover what caused the deaths,” the statement said, “including conducting toxicology reports. It may take several weeks for all of the test results to come in.”
The zoo’s remaining animals are doing fine, Stringfield said. Stingray Bay is a closed system that does not house any other marine life.
Since there were no conclusive results from the internal investigation, the zoo is bringing in outside experts in subjects such as water quality and animal care, Stringfield said. Like all animals, stingrays can get sick, but it will take some time and resources to figure out what happened in this case.
“We are broadening things and doing a really meticulous investigation,” she said, “and we’re bringing in outside experts to look at it with fresh eyes and broaden our thoughts of what could have happened.”
ZooTampa’s stingrays should not be confused with those inhabiting the Rays Touch Experience at St. Petersburg’s Tropicana Field, where baseball fans can interact with stingrays under the care of the Florida Aquarium.
The zoo announced the tragedy Thursday night on its Facebook page. The post garnered more than 600 comments and 4,500 reactions, which Stringfield said is a testament to the rays’ popularity.
Facebook users posted photos of themselves or their family members interacting with the animals and referred to some of the creatures by name, although Stringfield said the zoo never gave them official names.
“The outpouring of support and seeing how much those animals impacted the community,” she said, “that was something really amazing.”