Content area
Full Text
correspondence
Mystery behind Hitchcocks birds
To the Editor On 18 August 1961,a Californian newspaper reported that thousands of crazed seabirds pelted the shores of North Monterey Bay, California regurgitating anchovies. Soon aer reading the report (Supplementary Fig.S1), local visitor Alfred Hitchcock was inspired to produce his famous thriller The Birds. Three decades later, in 1991, another mass poisoning occurred in the same area this time, of sh-eating, disoriented and dying brown pelicans. But on this occasion the culprit was identied: the pelicans had ingested domoic acid, a neurotoxin that is produced by the diatom Pseudo-nitzschia. Large quantities of this diatom, and the associated toxin, were found in the stomachs of sh in the region. It has been suggested that diatom-generated domoic acid was also responsible for the 1961 event1,
but direct evidence has been lacking. Here we
show that plankton samples from the 1961 poisoning contained toxin-producing Pseudo-nitzschia, supporting the contention that these toxic diatoms were responsible for the bird frenzy that motivated Hitchcocks thriller.
Algal toxins such as domoic acid are increasingly recognized as the cause of marine poisoning events. Domoic acid is a chemical analogue of glutamate and, as such, binds with high affinity to glutamate receptors in the brain2. When domoic acid passes through the bloodbrain barrier and binds to these receptors in birds and mammals, it causes symptoms such as confusion, disorientation, scratching, seizures, coma and even death3.
Over the past decade, Monterey Bay,a productive coastal environment in the California Current upwelling system,has been aected by recurrent blooms of Pseudo-nitzschia species that produce domoic
acid. These blooms have led to the deathor stranding of brown pelicans, Brandts cormorants and sea-lions47. Although Pseudo-nitzschia has resided in the waters o California for millennia, domoic acid was only detected in diatoms in the region in 19918.
Prior to this, episodes of seabird mortalityo the shores of California were attributed to other factors such as fog, infectious diseases, oil spills and shing practices9. One such event was that...