A stingray exhibit at a Chicago zoo will be closed the rest of the summer after 54 of the animals died on Friday.
Staff at Brookfield did their best to save 54 stingrays, who died after the oxygen levels in their tank plummeted, the Chicago Tribune reported.
Friday afternoon, the stingrays -- all of whom were born in captivity -- started to become a bit sluggish in the shallow saltwater pool that serves as their home, and an exhibit for the public, the Chicago Sun Times added. Around the same time, a monitoring system that keeps track of its oxygen levels sounded an alarm, indicating they were low.
That alarm is connected directly to Bill Zeigler's cell phone -- he is the zoo's the environmental control officer and senior vice president of animal programs. Once he arrived at the pool, he, veterinarians, and the animal care unit got to work.
They closed the exhibit, herded spectators away, and did everything they could to get levels back to normal as staff walked the stingrays around the pool. Staff tried an air bubbler that releases pure oxygen, submerged air pumps, and a large pump.
"We went into triage at that time. And we began to help them swim to make sure water was passing over their gills. We had oxygen levels back up to normal within 20 minutes. But unfortunately it wasn't going to help."Most of the 54 stingrays died that afternoon, between 3 and 4:30 p.m. Several more succumbed that evening. Fifty cow-nose and four southern stingrays were killed, Zeigler confirmed.
"We are devastated by the tragic loss of these (54 rays). Our staff did everything possible to try and save (them), but the situation could not be reversed."Following these deaths, animal activists are heavily criticizing the Brookfield, and other similar ray exhibits, for being "death traps." Brittany Peet, with the People for the Ethical Treatment of Animals (PETA), pointed to another incident at Brookfield in 2008 to argue that its closure of the exhibit should be permanent.
In that incident, 16 perished when the water temperature jumped from 79 to 89 degrees.
"At this point, 70 … have died at the Brookfield Zoo as a result of malfunctions with their tank and it's time for them to close down their tank for good. Their lives are worth more than the cheap thrill of touching one … Seeing wild animals in captivity teaches people nothing about the true nature of these animals."In addition to these latest 54 deaths, and the 16 in 2008, 11 more died at the National Zoo in 2009.