Zoo has no idea what killed stingrays

2008-07-13

Calgary Herald

The Calgary Zoo still has no answer on what killed 40 cownose rays and will have to make a decision on whether or not to continue awaiting a lab's report on the cause of death.

In May, the rays died inexplicably months after the opening of a new hands-on exhibit.

Spokeswoman Laurie Herron said the exhibit's future is still up in the air. The zoo will have to decide whether to get more rays or some other aquatic animal.

That decision, Herron estimated, will have to be made within the month.

"If they can find an answer (to what killed the rays), they'd rather do that then make a decision without an answer. At some point, they may be forced to do that. They'd like to feel like they've done everything they can to find out what happened."

Herron said the lab has ruled out microbacterial problems and disease, but is still doing organic and in-organic toxins tests.

"Our senior management team will probably ask them to continue on for a little while longer. I don't think they're ready to give up the search to see if they can uncover what it was. We were told early on by the lab that there are literally hundreds of thousands of compounds that are potentially dangerous to fish. It's a tough search."

Two weeks ago, the two surviving rays were moved back into the exhibit pool after it was cleaned and tested. Vets felt the exhibit's pool gave them more room to swim.

The exhibit is behind a fence and manned by a staff member.