By SUSAN PALMER/YachatsNews
Mammals — both marine and terrestrial — are headed for Oregon beaches this spring and Jim Rice would like a word with the humans.
Rice, stranding program manager for Oregon State University’s Marine Mammal Institute, is the guy who gets the call when people stumble on seals and sea lions — the charismatic megafauna that can make visiting the coast such a vibrant experience. Rice oversees the Newport-based Oregon Marine Mammal Stranding Network — state agencies, universities, aquariums and volunteers — that collaborate to track the health of marine mammals.
Spring is when harbor seal pups appear on beaches, often near the mouths of rivers. This is also the time of year that adult California sea lions may be found — not at their usual rocky offshore haul-outs but right there on sandy beaches where dogs race about in free-wheeling delight and bare-foot people kick through the surf.
Few beachgoers can resist the desire for a close-up look at these fascinating mammals, but Rice warns that it’s best to give them a wide berth.
California sea lions may be in the middle of a bacterial disease outbreak called leptospirosis, which can jump species, infecting both dogs and humans. Leptospirosis periodically cycles through California sea lions and last year an outbreak began among Oregon’s population. Of the 256 California sea lion strandings reported on the Oregon coast, 23 were necropsied, 14 were checked for Leptospira, the organism that causes leptospirosis, and nine tested positive.
“Given the high numbers of California sea lions that were reported overall, many of which displayed clinical signs of leptospirosis on beaches but were never found dead or never necropsied, it seems likely that there were many more positive cases than we were able to test and conclusively diagnose,” Rice said.
Typical outbreaks often last a couple of years.
“We had an outbreak in 2009 that went into 2010; and then in 2017 we had one that went into 2018,” he said. “We may be seeing a continuation of the spike we had this past year.”
Leptospirosis is one of the zoonotic diseases, meaning it can move from animals to humans. In a post-pandemic environment, researchers have taken a much deeper interest.
The Oregon Department of Fish and Wildlife has received a federal grant to study them in marine environments. Part of the funding will be used to create a network along the West Coast that will allow scientists to more effectively share information. Known as the Eastern Pacific Marine One Health Coalition, it will link state agencies and universities from Washington, Oregon and California.
ODFW disease research
Leptospirosis presents an interesting case for researchers. It’s well known in terrestrial environments, said Julia Burco, an ODFW wildlife veterinarian and lead researcher on the grant. Smaller mammals carry it, she said, and people with horses and dogs are often advised to have their animals vaccinated.
“There’s a lot of terrestrial cycles of leptospirosis and sometimes animals can do just fine and can clear an infection, but sometimes they can get really sick,” she said.
Researchers don’t fully understand how this bacterial infection jumps from land mammals to California sea lions.
“The bacteria really shouldn’t like to be living in the salt water environment so it is interesting that it periodically shows up in these sea lions,” she said.
Among the other zoonotic diseases the new coalition will be keeping an eye out for is avian influenza, which has begun to show up in marine mammals in other parts of the world, but has yet to be seen on the Pacific coast, Burco said.
It could be devastating to local marine mammals and might also have implications for terrestrial mammals, including people should the flu virus change, she said.
“A lot of this funding came from the zoonotic disease initiative through the U.S. Fish and Wildlife Service out of the covid funds, to predict some of these zoonotic diseases that are coming up on the landscape and their impact on wildlife, domestic animals and people,” she said.
The overarching goal: “Making sure that people, animals and the environment are healthy and for early detection of any problems that arise,” she said.
For now, the message is simply to be wary of stranded marine mammals, Burco and Rice say.
Careful with pets
Veterinarian Charles Hurty echoes that message.
Hurty, a vet at Grove Veterinary Clinic in Newport, has first-hand experience with leptospirosis. Years ago, while working in Georgia, he contracted it while treating one of six dogs suffering from the illness. Everyone at the clinic who came in contact with the dogs tested positive for the disease, and three of the dogs died, Hurty said. A timely course of antibiotics cleared the illness among the infected people, he said.
Leptospirosis cases are rare in Newport. Grove Clinic, which staffs five vets, probably sees just a couple of cases a year, Hurty estimates.
“The cases are few and far between,” he said.
But the disease, left untreated, leads to kidney failure or liver failure and dogs can quickly succumb without treatment, he said. Symptoms can include lethargy, drinking more water, vomiting, lack of appetite, fever, increased urination and jaundice.
Sometimes the clinical signs can be more subtle. Screening for the infection can be done quickly, requiring only a blood sample, Hurty said.
A vaccine is available for dogs and while it’s not 100 percent protective, it does reduce the risk and the severity of illness, he said. Vets in his office will often assess the risk with dog owners. A dogs who frequent beaches, live on a farm, or spend time in wildlife habitats may be more at risk, he said.
Let nature take its course
Seal pups, on the other hand, pose no risk to people or their pets, but are at risk from them. Still too young to spend as much time in the water as adults, their moms will leave pups on the beach while they feed. When they return, if people or dogs are near the pups moms won’t approach and in some cases may abandon their offspring, Rice said.
“We need to drive home the point that they have to be left alone so that mom can safely come ashore to nurse. … Unless the mother and pup can reunite the pup isn’t going to survive,” he said.
Rice and his team don’t swoop in to save the day when they get a call about a baby seal or a sick sea lion, which surprises many people who call the network.
“Sea lions and harbor seals are at the upward population limit of what the environment can support,” he said. “Rehabilitating these animals does not provide a conservation benefit.”
The ODFW policy is to let nature takes its course, he said.
That doesn’t mean the stranding network never gets involved, particularly if an animal is on the list of species threatened with or in danger of extinction. Every year, a dozen or so sea turtles wash onto Oregon beaches near death from exposure to frigid waters, and frequently get rehabilitated and returned to the ocean through the intervention of aquarium staff.
Rice and his network also occasionally respond to animals tangled in fishing gear.
“We’ve been able to remove the gear and rescue the animal without putting them into rehab, enabling them to get back into the water and swim freely,” he said.
Rice emphasized that he knows visiting Oregon’s beaches is important to people and their pets. He encourages visitors to keep coming but to be smart about it. Folks can postpone letting a dog run free until they’ve inspected a stretch of beach and feel confident no pups or ailing sea lions are nearby.
“People should be responsible with their pets and keep them away from wildlife, “ he said. “ My dog loves the beach and we love to watch him run on the beach. … The message should be that people should exercise restraint.”
- Susan Palmer is a Eugene-based journalist. To see more of her work go here.
To keep baby seals safe, people should either keep their dogs leashed or have trained their dogs to reliable (100% reliable) voice control so that their dogs aren’t all over the beach and make sure their dogs stay within easy hearing distance of their voice, rather then freely harassing wildlife such as shore birds and baby seals. I walk on beaches in and around Newport fairly often all year, as soon as the weather improves, there’s always a percentage of dogs under zero control, chasing what birds still try to land and feed near the water’s edge or further away from the water, including snowy plovers trying to nest, or spooking black oystercatchers trying to feed (on rocky ridges exposed at low tides by the latter or in creeks flowing into the ocean) or bathe in fresh water as it flows into the ocean, great blue herons standing/stalking along the shore or in creeks flowing on their way to the ocean. Some surfers bring their dogs to the beach with them (particularly in the Otter Rock area), leave them to do as they please while they’re surfing. Some of those dogs chase other dogs, shore birds, steal balls from other dogs, etc. Please keep your dogs with you, don’t focus on your cellphone calls, your run/jog or chatting w/your friends, instead of paying attention to your dog. The beaches aren’t really large dog parks minus dog park rules — which is what very visible minority of dog owners seem to believe. People who are afraid of dogs, who don’t like dogs, who have balance issues and so are concerned about being jumped on or shoved by a dog charging past to chase a flock of plovers, whimbrels or a group of gulls, have as much right to peacefully enjoy the beach as people with dogs do.