Written By: Terri Pressley
In 1961, Northern California was hit by a deluge of seabirds that flew into homes, attacked and frightened seaside dwellers near the once sleepy California coastal town of Monterey Bay, Alfred Hitchcock decided that he would make a film about the incident and do what he does best. Scare the heck out of moviegoers. However, what caused the birds to attack to begin with?
Hitchcock, pioneer and master of psychological thriller, left cinema-goers terrified in 1963 with his movie The Birds, in which the life of a couple who live in a small, coastal Northern California town is turned upside down as birds of all kinds suddenly begin to attack people in increasing numbers and with increasing viciousness. Can our feathered friends can actually turn into vicious killing machines?
The mystery seems to have been solved by Sibel Bargu, an oceanographic researcher at Louisiana State University in Baton Rouge. Bargu, an ardent fan of Hitchcock's movies, was left deeply impressed by The Birds when she was a child and took it upon herself to crack the mystery behind whether it was possible for birds to attack humans.
On Aug. 18, 1961, a local newspaper reported that thousands of crazed seabirds were sighted on the shores of North Monterey Bay in California. The birds called sooty shearwaters, regurgitated and then flew into objects and died on the streets.
Hitchcock, visting in the region at the time, showed interest in the event and called the ‘Santa Cruz Sentinel’ for more information, according to Bargu.
The frenzy helped inspire Hitchcock's 1963 thriller "The Birds," which was adapted from a short story by Daphne du Maurier. In the movie, flocks of birds attack and kill residents in a community on the California coast. The cause of the outbreak in 1961 was never identified. 30 years later, disorientation and death struck brown pelicans in the same area.
"It looks like attacking, but it's actually crashing into walls, because they are very disoriented," Bargu said. This time, they found that the birds had eaten a toxin, domoic acid, produced by multiple species of Pseudo-nitzschia, which are diatoms, a type of algae.
Domoic acid can cause confusion, disorientation, scratching, seizures, and death in birds that eat the fish that ate the algae and becomes concentrated as it moves up the food chain.
Bargu and colleagues looked back about half a century by examining the gut contents of tiny floating marine animals, called zooplankton, collected July-August of 1961 in Monterey Bay and now housed in a collection at the Scripps Institution of Oceanography.
They found that toxin-producing species of Pseudo-nitzschia accounted for 79 percent of the diatoms present in the guts of these tiny animals at the time.
"We suggest that domoic acid generated by these diatoms accumulated in the food chain and led to the poisoning of migratory flocks of shearwater that foraged in these waters," Bargu wrote in a study published in the January 2012 issue of the journal Nature Geoscience.
Solving the mystery does not take away from The Birds the honor of being the one of the best thrillers of all time. Hitchcock had put in quite an effort to recreate the scene of attack, assembling mechanical birds and even training hundreds of real birds. Though nominated for the Academy Award for Best Special Effects in 1964, the film did not win (the winner that year was Cleopatra).