Sick sea lions are washing up on SLO County shores, and more are expected

Diana Kramer knew it was going to be a long week Monday as she and her team responded to calls of a sea lion in distress at Oceano Dunes.

That’s when the Marine Mammal Center operations manager noticed another sea lion in the same location also displaying symptoms of disorientation.

“At the same time, we got calls for at least two others,” Kramer said Friday. “And from that point on, it has not slowed down.”

She said the Marine Mammal Center has rescued 20 sick sea lions along San Luis Obispo County shores — all displaying symptoms of “domoic acid toxicosis” — since Monday, and she expected to hit the 30 mark sometime Friday.

By late Friday morning, Kramer said she had received calls for eight stranded sea lions.

“And that’s just this morning, and it’s still early,” she said.

The illness, which can affect various species of marine mammals, is caused when an animal ingests small fish such as sardines and anchovies that have eaten toxic algae.

While the sickness has yet to be formally diagnosed, Kramer said domoic acid is the likely source.

“99 percent of the animals we have gotten over the past few weeks have all been experiencing the same symptoms,” Kramer said.

Symptoms include disorientation, a distinctive “head-bobbing” and, more concerning to rescuers, seizures.

Kramer noted that most of the Marine Mammal Center’s patients have been mature juvenile sea lions weighing around 130 pounds.

But while the diagnosis appears to be certain, the cause of the algae blooms is far from it.

“One factor that might cause it is warmer water,” Kramer said, adding that incidents of domoic acid poisoning tend to increase in the summer months.

Another possible contributor to the algae explosion is an increase in fertilizer run-off into the ocean.

“But we don’t actually ... know for certain yet why, for certain times a year, we see this huge increase,” Kramer said.

While sea lions are the primary species to exhibit domoic acid poisoning in San Luis Obispo County, Kramer said earlier this year there were reports of “multiple dolphins stranded on shore having seizures in Ventura and Santa Barbara counties.”

Kramer said she has seven sea lions on-site Friday morning. The SLO office of the Marine Mammal Center is primarily volunteer-run, and serves as a triage facility where animals can be stabilized and then sent to the Marine Mammal Center in Monterey Bay and from there to the main facility in Sausalito.

Kramer’s team treats the animals by “flushing them out” by injecting “a high volume of fluids ... just under the skin.”

The sea lions also are put on anti-seizure medication — the same kind used by humans, Kramer said — and, if they can eat, fed fish not contaminated by domoic acid.

Kramer said there have been a few fatalities, but most of the sea lions in treatment are in guarded condition. She said it’s all a matter of how quickly sick sea lions can be discovered; the greater the quantity of ingested acid, the more likely that the domoic acid will cause permanent damage.

That includes shrinking the sea lions’ hippocampus — the portion of the brain that governs memory and learning — and even causing miscarriages.

With 600 miles of coastline to cover, Kramer said her team’s resources are “stretched to the limit,” and she urged the public to help out in any way they can.

That can include donating money or volunteering time, but it can be as simple as being the eyes and ears of the center when out at the beach.

People who see a sick animal can call the Distressed Marine Mammal hotline at 415-289-7325.

This story was originally published July 21, 2017 at 4:55 PM with the headline "Sick sea lions are washing up on SLO County shores, and more are expected."