Deadly Sea Lion Bacterial Infection Poses Threat To Dogs

SAN FRANCISCO — An uptick in sea lions infected with a deadly bacteria has officials at The Marine Mammal Center issuing a warning to dog owners throughout the Bay Area.

Leptospirosis can be fatal to sea lions with only about one-third of those infected recovering from the disease, Marine Mammal Center spokesperson Giancarlo Rulli said, adding that the center started seeing an increase in calls regarding sick and even dead sea lions about a month ago.

Most of the calls came from Sonoma and Medocino counties, "most notably in Fort Bragg" he said.

Rulli said male sea lions are returning to the area from their breeding grounds near the Channel Islands. Most of the sick sea lions were juvenile males between the ages of 2 and 4 years old.

"Leptospirosis is a bacteria that can cause kidney failure in sea lions," Rulli said. "Typically we see this disease pop up every four to five years. It tends to have a cyclical pattern where it seems to impact primarily California sea lions."

Rulli said the disease has been found from San Luis Obispo County up into Mendecino County and roughly 7o sea lions are suspected to have leptospirosis.

"That number is trending slightly behind where we were last year when we had roughly 100 sea lions in the hospital for suspected leptospirosis," Rulli said. "To put it in perspective in 2018 we had roughly 300 sea lions with suspected leptospirosis in the hospital."

Rulli said its important to remind dog owners to keep their pups away from sea lions since the bacteria can also be deadly to dogs.

"Beachgoers with dogs really need to keep their dogs on a leash," Rulli said, adding that a safe distance is at least 50 yards away from any marine mammal. "Leptospirosis can have serious, potentially fatal side effects to dogs."

Sea lions with leptospirosis will appear lethargic and have their flippers tucked close to their bodies. Dead sea lions can still pass along the bacteria, he said.

According to Rulli, when a dog gets infected there is a one- to two-week delay before leptospirosis symptoms appear.

"It will typically show up as a fever but it can cause kidney and liver failure," he said.

If you take your dog around the water frequently, you should consider getting the leptospirosis vaccine that is available for dogs.

"The next time you talk to or visit your veterinarian ask about whether your dog is up to date on the leptospirosis vaccine," Rulli said.

As for the sick sea lions, the center is giving them antibiotics and other treatments, Rulli said.

"The problem with leptospirosis is sea lions are an incredibly resilient species so by the time they are washing ashore sick, the disease has really taken root," he said, adding that the center's veterinary teams are fighting an uphill battle to save those infected with the bacteria.

"They are very debilitated by the time they come ashore and we receive the calls to respond to them," he said. "Leptospirosis is a painful disease."

Rulli said if beachgoers see a seal or sea lion in distress, they should maintain that safe distance and call The Marine Mammal Center hotline at (415) 289-SEAL (7325).

Beachgoers who find a dead seal or sea lion should call the California Academy of Sciences at (415) 379-5381.