The Fresno Chaffee Zoo’s 8-year-old California sea lion, Catalina, died Saturday after contracting Valley fever, the zoo announced Wednesday.
Zoo officials say Valley fever is an uncommon cause of death for their animals, so rare that they are unable to confirm any previous Valley-fever-related deaths.
Because it’s so rare, Chief Veterinarian Shannon Nodolf said it wasn’t an ailment zoo veterinarians had considered.
The zoo delayed announcing Catalina’s death to await the results of a necropsy, which was done at the state laboratory in Tulare. It was initially thought that Catalina died of cancer.
“It is possible she had it (Valley fever) before she came here,” Nodolf said.
She said Catalina had appeared fairly healthy until she was found dead in her enclosure Saturday.
Catalina had some gastrointestinal issues in recent weeks, an apparent minor illness she had bounced back from.
The sea lion had previously undergone chest X-rays but wasn’t coughing or having trouble breathing, Nodolf said. However, the necropsy showed she had “little lung architecture left.”
Catalina may have had a seizure and died, she said.
“The signs didn’t say this was Valley fever,” Nodolf said.
Valley fever isn’t contagious, but it is a common fungal ailment especially prevalent in the southern San Joaquin Valley and in parts of Arizona.
“Valley fever is an uncommon disease in marine mammals, but we do see it occasionally here in the Valley,” she said. “The rest of our animals here are being carefully monitored, making sure we don’t see any other signs or any other symptoms in any of our other animals.”
Smaller animal veterinarians asked about Valley fever said it’s extremely rare. One said he hasn’t seen a case in three years.
On Saturday morning, Catalina didn’t eat, but that didn’t seem unusual.
Because sea lions perform in zoo shows they are closely monitored, said Scott Barton, the zoo’s director.
“Usually you would see a gradual decline. We didn’t see that here,” he said.
Keepers arrived within minutes of someone finding her body and immediately began performing CPR.
Catalina came to Fresno in January 2010 after she was rescued by the Fort MacArthur Marine Mammal Center in Los Angeles. The zoo said a rear flipper injury that resulted in lost digits – most likely caused by a shark bite – would have prevented Catalina from surviving at sea.