Natural toxin is killing birds, sea lions

Dozens of birds, sea lions and even whales and dolphins have been turning up sick or dead on beaches from Los Angeles to Laguna Beach, in one of the most severe incidents of domoic acid poisoning local animal control workers have ever seen.

About 78 birds have been seen by the Wetlands and Wildlife Care Center in Huntington Beach since Sunday, and in that time the Pacific Marine Mammal Center in Laguna Beach has taken in about 20 sea lions. Many of the animals died.

Domoic acid is produced naturally by algae blooms, which typically occur in the spring and early summer, said Astrid Schnetzer, a research assistant professor at USC.

It’s not clear what makes the algae produce domoic acid — a toxin to animals that can cause seizures and death — but Schnetzer said it could be related to the amount of nutrients in the water.

Test results on samples from the sick animals are expected today. Necropsies on birds brought to the Wetlands and Wildlife Care Center revealed symptoms of domoic acid poisoning, center director Lisa Birkle said.

It’s normal to see a few birds acting drunk and disoriented after eating fish that ate the acid-producing algae.

What is unusual about this week’s poisonings is that so many of the birds are dying, Birkle said.

“Usually we’ll be able to get more live birds and be able to stabilize them,” she said. “We’re not sure why all the birds are dying before we can treat them.”

Of the 78 birds brought to the center, 11 were alive Thursday afternoon. At the Pacific Marine Mammal Center, nine of the 20 sea lions brought in survived, said Emily Wing, the center’s director of development and marketing.

Only a few species of phytoplankton produce domoic acid, and one particular species has been producing a lot more of it than usual in the last three years, Orange Coast College marine biology professor Dennis Kelly said.

“Something changed in our local ocean, and it favors the stuff,” he said. “All of a sudden we’re seeing thousands of those little cells instead of dozens or none at all.”

Domoic acid can also be a toxin to people, and that’s what concerns Kelly.

Sea animals get sick when they eat fish that have consumed domoic acid, and “some of those fish are fish that people eat, like sardines or anchovy,” he said.