The Calgary Zoo staff is stunned after the mysterious deaths of 34 of 43 stingrays in its popular aquatic exhibit on Sunday and yesterday.
The zoo closed the stingray exhibit after a ray keeper noticed “erratic behaviour” from the aquatic creatures; 26 died within two hours, and eight more perished yesterday — for a total of 34. Nine more are in quarantine at the zoo.
“I think the zoo staff and especially the veterinarians are obviously very upset. The rays were such an engaging and popular attraction,” Cathy Gaviller, director of conservation, education and research told Metro.
The deaths come as a total shock to the zoo, said Gaviller, adding that the creatures were seemingly fine and water tests conducted daily were normal.
“What we do know is that there was no mechanical failure in the life support system. We will be relentless in investigating the cause.”
While necropsies on the dead rays showed signs of distress and irritation of the gills, zoo officials were unable to explain the sudden deaths. Calgary Zoo veterinarian Dr. Doug Whiteside said there might have been a change in the water.
The vet said they aren’t ruling out sabotage of the marine tank as a cause for the stingray deaths.
“We don’t want to think someone would do this, but we have to look at all possibilities but that would be very sad if that was the case,” Whiteside said.
Zoocheck Canada executive director Rob Laidlaw told Metro this is another troubling incident for the zoo.
“It’s a serious problem. And the Calgary Zoo seems to have a lot of them. It’s been one fiasco after another after another for them,” Laidlaw said.
Zoo visitor Rochelle Peters and her kids just visited the stingrays recently and she wonders if the deaths are due to “overstimulation.”
“I would think a lot of people are sticking their hands in there and touching them. Maybe it’s not good for them and it’s just too much,” Peters said.
The zoo is awaiting toxicology results to help determine what, if anything, was wrong with the water. Results are expected within a couple of weeks.