Toxic algae proves fatal for marine life

LOS ANGELES -- Birds falling from the sky. Pelicans having seizures. Dolphins dying on beaches.

For two months, a growing number of marine mammals and birds has been dying along the California coast. About 70 dolphins have washed up on state beaches, while more than 200 sea lions and 200 seabirds have gotten sick or died.

One of the leading suspects is domoic acid, a potent toxin that attacks the brain. The naturally occurring toxin is produced by the plankton species Pseudo-nitzschia.

The toxin moves up the food chain from the slender, glass-shelled diatoms to sardines, anchovies, crabs and other shellfish that, in turn, become dinner for birds and marine mammals.

"There's dead pelicans on the beach, and then these weird ones having seizures," said Jay Holcomb, director of the International Bird Rescue Research Center. "We had the public calling in, saying, 'These birds are falling out of the sky."'

Blooms of Pseudo-nitzschia have occurred before but experts said it was only recently that sealife kills were linked to them.

Scientists caution that other types of microscopic sea life also can produce toxins.

This month record high levels of domoic acid, ranging up to 380 parts per million, have been found in mussels taken from Santa Barbara waters. The federal alert level is 20 ppm, said Gregg Langlois, a marine biologist with the state Department of Health Services.

Some researchers believe domoic acid poisoning caused a 1961 incident that partly inspired Alfred Hitchcock's "The Birds." Seabirds that may have eaten tainted anchovies descended on Santa Cruz-area villages, nipping people, staggering around, smashing windows and smacking into cars and houses.

No human illnesses have been reported in California but state health officials advise against eating locally sport-harvested shellfish, crabs, sardines and anchovies.

Commercially harvested seafood is considered safe because it is inspected.

Humans eating tainted seafood can get amnesic shellfish poisoning, which can cause twitching, nausea, permanent short-term memory loss and even death.

Domoic acid suspected

High domoic acid levels prompted a partial shutdown of mussel harvesting along Prince Edward Island in Canada last month. The link between the acid and human illness was discovered there in 1987 after more than 100 islanders became ill and several died from eating tainted mussels.

In 1991 the crab season in Washington, Oregon and California was halted after tests detected domoic acid in crab meat. The deaths of more than 400 California sea lions in 1998 also were traced to the acid.

But research into the plankton is so recent that nobody is sure what sparks the algae growth or why the cells produce different levels of the toxin at different times.

California's long coastline means many more animals might have perished out of sight of the public. Also, the deaths could have a larger impact by whittling down isolated breeding colonies and by killing off mothers during breeding season.

By some estimates, harmful algal blooms have caused more than $1 billion in losses in the United States in the past several decades, including loss of tourism, fisheries and the costs of treating public illnesses, according to the National Oceanic and Atmospheric Administration.

Some bacteria and viruses attack certain algae species but more research is needed before a biological remedy might be available. Even then, the impact on the environment would be uncertain.

"It's a complex biological system and I don't think we have any idea of what will happen if you begin to perturb it," said Christopher Scholin, staff scientist with the Monterey Bay Aquarium Research Institute. "You might get something worse."

The latest outbreak began in March in northern California. The high levels found in Santa Cruz and Monterey Bay subsided and the problem now is concentrated in the south, Langlois said.

The Marine Mammal Care Center in San Pedro has treated about 170 sea lions. "They come in exhibiting seizures. Some are comatose. They're disoriented, lethargic," director Jackie Jaakola said.

"It's pretty overwhelming," she said. "This is also one of the saddest things we've seen. This is really hard."

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On the Net:

Marine Mammal Care Center: http://www.mar3ine.org/mmcc/

Algal bloom information: http://www.redtide.whoi.edu/hab/

NOAA: http://state-of-coast.noaa.gov/bulletins/html/hab--14/hab.html