Medical staff and officials at the Calgary Zoo are trying to find out what killed 34 cownose stingrays in the span of just 24 hours.
Just nine stingrays remain of what used to be a school of 43. The animals were part of the Calgary Zoo's newest exhibit, which cost $250,000 to set up. But on Sunday afternoon staff noticed the stingrays were acting strangely and within hours most were dead.
"To say that people are saddened and shocked is an understatement," Cathy Gaviller of the Calgary Zoo told CTV News Calgary.
Zoo officials told CTV Calgary that it took just three hours for 26 of the stingrays to die Sunday. Eight more had died by Monday morning. The cause of their deaths remains a mystery, but there are concerns that the water in the main tank may be to blame.