|The Science Behind Hitchcock's 'The Birds'|
When thousands of frenzied seabirds invaded the coastline near Monterey, Calif., in the summer of 1961, the scene played out like a Hollywood horror movie. The Santa Cruz Sentinel reported a “rain” of birds known as Sooty Shearwaters slamming into homes and other shoreline structures.
“Dead and stunned seabirds littered the streets and roads in the foggy early dawn,” the newspaper reported on August 18, 1961.
Two years later, a similar plotline made it onto the big screen through the eyes of filmmaker Alfred Hitchcock—in the Macabre form of The Birds. The master of suspense and mystery, responsible for Psycho, Rear Window and other classics, happened to be visiting the area during the bird invasion. The event fueled inspiration for the film (along with a chilling avian story published in 1952 by British author Daphne du Maurier).
And now scientists have produced fresh evidence of what caused the birds to go crazy.
A team that includes Mark Ohman of Scripps Institution of Oceanography at UC San Diego recently reported in Nature Geoscience that high quantities of Pseudo-nitzschia, a type of phytoplankton, produced a neuro- toxin that likely moved up the food chain and was eventually gobbled up by the birds.
The researchers say the neurotoxin—known as domoic acid—poisons the brain and “causes symptoms such as confusion, disorientation, scratching, seizures, coma and even death.”
The key behind the new findings was the ability to travel back in time to study ocean samples from a half-century prior. The California Cooperative Oceanic Fisheries Investigations (CalCOFI), one of the world’s longest continuous marine monitoring programs, provided the necessary samples now stored in the Scripps Pelagic Invertebrate Collection, a library of archived marine samples. Such resources allowed Ohman and his colleagues to study the gut contents of several specimens of grazing zooplankton that were captured off Monterey prior to the bird frenzy.
It is an example, says Ohman, of how detailed and carefully preserved geo-referenced materials can provide answers to questions that were never anticipated when they were being collected.
—Mario C. Aguilera, ’89