'The Birds,' sea lions deaths linked

By ED SUSMAN UPI Science News

ANAHEIM, Calif., Jan. 21 (UPI) -- Director Alfred Hitchcock, in his brutal and disturbing film thriller, "The Birds," never explained why the feathered creatures suddenly go psycho, but scientists now think they have an answer.

Researchers speculated today that the dramatized actions of crazed birds could have been caused by a natural poisoning -- the same toxin responsible for a sea lion kill on the California coast last year.

Mary Silver, professor of ocean sciences at the University of California, Santa Cruz, said Hitchcock was aware of bizarre behavior of flocks of seagulls two years before his film.

In 1961, Silver explained, flocks of seagulls began acting funny. Newspapers featured pictures of dead gulls that had "attacked" police cars. "There were a lot of phone calls to the local newspaper about the incident," Silver said, "from a film director named Alfred Hitchcock."

In 1963, Hitchcock's film, based on a short story by Daphne du Maurier made Americans everywhere terrified of seeing more than two pigeons together on a city street.

Du Maurier gave no reason for the birds strange behavior in her short story written in 1952.

At a symposium of the National Sea Grant College Program, held in conjunction with the annual meeting of the American Association for the Advancement of Science in Anaheim, Calif., Silver said investigations into the sea lion kills along the coast of central California in 1998 in which dozens of the animals went into convulsions and died led scientists to suspect a food chain poisoning event.

A harmful algae bloom produced domoic acid -- a neurotoxin that can be fatal in humans. As larger organisms such as mollusks and certain fish feed on the phytoplankton, the toxin climbs the food chain.

Silver said schools of migrating anchovy ingested toxin-contaminated organisms and then the anchovy were eaten by birds or other animals such as sea lions.

The toxins can cause convulsions, nausea, vomiting, diarrhea, limb weakness among several species. Cultures taken from fecal waste of the convulsing sea lion confirmed domoic acid poisoning, Silver said.

"We think these outbreaks happen frequently in nature," Silver said. "We just didn't pay any attention to it." A major bird kill and the sea lion kill in the 1990s brought the extent of domoic acid poisoning into focus, she said.

Silver said earlier reports dating back to at least the 1930s of strange behavior among marine wildlife suggests these might also have been caused by a domoic acid outbreak -- including the 1961 Santa Cruz bird activity that caught Hitchcock's attention.