Sea Lions on the North Coast are Experiencing a Leptospirosis Outbreak

Reports of sick sea lions have come in from across the north-coast this year. Director at the North Coast Marine Mammal Center, Karen Helms explains why these animals are getting sick and what you should do if you encounter them.

“We have been seeing an unusually large number of California sea lions with leptospirosis and we’re calling it an official mortality event, because there have been much more than usual,” Helms said. “It’s something that happens almost every year to some degree, usually every couple of 2 to 4 years, we’ll see a little higher level than usual but this year has been the highest in the last ten years or so, that I’m aware of.”

But what is leptospirosis and why is it affecting so many sea lions? 

“It’s a bacterial infection that attacks their kidneys, their liver, their reproductive systems, and it can cause acute renal failure and it can lead to death,” Helms said. “When you have runoff after it rains and it goes into the ocean, you know, the fish are eating the things that are absorbing bacteria. and then the sea lions eat the fish and they end up with leptospirosis.”

The signs are hard to miss, like drinking water they’re not supposed to.

“They will often be drinking a lot of saltwater and they’ll be in the shallows drinking saltwater off the sand, you’ll see them kind of suckling on the sand,” Helms said. “They’re very lethargic, they will also typically have their rear flippers tucked up under their bodies because of the discomfort that’s caused in the abdominal area.”

If you  do come across a sick sea lion on the beach do not get close to it—especially if you’re with your pet.

“It is transmissible to people and pets and you don’t even have to come in contact with the animal to catch leptospirosis,” Helms said. “They shed the leptospirosis in their urine and so if they have urine on a patch of damp sand, when your dog walks through that and then licks his paws, it can end up with leptospirosis.”

If you do see a sick animal on the beach–keep your distance, stay calm and always remember to call the experts. 

Visit: https://northcoastmmc.org/Rescue Hotline: 707-951-4722