OKC Zoo's Harbor Seal Dies Following Dental Surgery

A harbor seal at the Oklahoma City Zoo has died following a dental surgery Wednesday afternoon.

According to zoo officials, the dental procedure was performed on Leo, a 7-year-old harbor seal, to treat a severe tooth abscess.

Although Leo's vital signs initially were strong following the surgery, officials say his heart rate suddenly dropped, and despite resuscitation efforts, he never fully regained consciousness.

"We monitored Leo closely days before the procedure and followed the standard protocol for marine mammals regarding anesthesia according to the Pacific Marine Mammal Center (PMMC) in Laguna Beach, California," said Jennifer D'Agostino, Zoo veterinary services director. "All signs pointed to him doing well."

Harbor seals are generally at higher risk of complications under anesthesia, because of their deep-dive response, which significantly slows the heart rate as their body adapts to water depths, according to D'Agostino.

Necropsy (animal autopsy) reports showed some small lesions in the heart muscle that may or may not have been associated with his death but could have resulted from Leo being stranded as an infant. Tissue samples are pending.

Leo came to the Zoo in April 2007 when he was a one-year-old pup. He was rescued by the former Friends of the Sea Lion Marine Mammal Center, now PMMC, but not released back into the ocean due to blindness in both eyes.

According to zoo officials, Leo lived with Liberty, a female harbor seal, in the pinniped pool of the Zoo's Noble Aquatic Center "Aquaticus" for six years.