Poisoned seas persist

Animal rescue and academic research organizations are working together to understand and stop the deadly proliferation of a natural toxic algae that has claimed the lives of hundreds of sea animals over the past month in Southern California waters.

Nearly 50 sea lions — most of them pregnant — have died in less than a month at the Pacific Marine Mammal Center in Laguna Beach.

The poison comes from a bloom of algae that produces the poisonous neurotoxin domoic acid, and wildlife experts are clamoring to stop it from killing more sea creatures.

The toxin has been registered at twice the amount ever recorded during an algae bloom, USC researcher Dave Caron said at a press conference held this week in San Pedro to raise public awareness of the toxin’s effects.

Laguna’s marine mammal center has attempted to save 53 sea lions picked up across Orange County since April 14. Nine of them were retrieved off Laguna Beach’s shores; most of them were too sick to be saved.

Of those 53, only five still survive. The center’s director of marketing and development, Emily Wing, said most of those that died were pregnant.

“It’s hard to lose so many animals in such a short time,” Wing said.

The center recently released nine rescued sea lion pups at Crescent Bay beach, none of which have returned to the center so far, Wing said.

The Marine Mammal Care Center in San Pedro is so full that ailing sea lions have to be left on the beach for 48 hours before they are brought in.

Sea lions have a gestation cycle that has most females pregnant through spring and having pups in early summer. This coincides with the spring algae blooms as they start birthing pups.

Because sea lions ingest domoic acid through eating filter-feeding fish such as anchovies and sardines, the pregnant females tend to get sicker. Pregnant females have to eat more than a male or nonpregnant female, hence the higher death rate.

Sea lions affected by the acid seizure rub excessively and bob their heads. Marine birds and cetaceans such as dolphins don’t have the same symptoms, making them even harder to save.

The Wetlands and Wildlife Care Center in Huntington Beach has attempted to bring in 165 marine birds in to the center, but 144 were dead on arrival. Eight died while being treated, and 13 are still alive.

Debbie McGuire, the wildlife center’s director, said there are also many bags of dead birds brought to the center that have yet to be tested.

“I’m running out of room in my freezer,” McGuire said.

Caron, of USC’s biology school, is an expert on marine microorganisms and has been studying the bloom of acid producing algae. Caron said the acid is diminishing for now, but may be back again this or next spring.

The acid is a neurotoxin that causes nerve damage, especially to the hippocampus part of the brain, which affects memory. The poison acts like a transmitter in the brain and makes the neurons go haywire.

The damage can cause the animals to forget to eat or breathe. The overuse causes the brain to shut down.

“It causes neurons to fire until, literally, they burn out,” Caron said.

Caron said the strain of algae has a bloom every spring, but the amount of domoic acid produced by this bloom is twice the amount ever recorded before in the world.

Caron said the extreme amount of domoic acid could be caused by either a higher concentration of the acid-causing cells or by a regular number of cells overproducing the acid, but his lab has been unable to discern which case it is.

There have consistently been domoic acid kill-offs in Southern California’s waters over the last few years, but none of them have been nearly as bad as this year’s, Caron said. He said there is a possibility of domoic acid buildup in marine animals over these years, but the effects this might have haven’t been explored yet.

Because the acid is only created by this strain of algae under certain conditions, Caron said he is fairly sure the acid is a result of a certain set of nutrients the algae is getting. Whether it is linked to human activity hasn’t been determined yet.

“Discharges from land may be contributing to the bloom, but I just can’t confirm that yet,” Caron said.

The Pacific Marine Mammal Care Center asks beachgoers who see a distressed sea lion to immediately call the center at (949) 494-3050. Wing said it’s important to keep a distance from beached sea lions. As the animals are wild and could be a danger to people, you should never try to push an animal back into the water, feed it or try to pour water on it. If the animal is already dead, contact local lifeguards or park rangers.