1991 Domoic Acid Outbreak
September--Sick Seabirds in Monterey Bay
October/November--Domoic Acid Detected on Washington Coast
Transported from California by currents?
Notes:
Slide 4. 1991 DOMOIC ACID OUTBREAK (1st time DA detected on West Coast)
-SEPTEMBER: Sick seabirds in Monterey Bay
-“acting drunk, swimming in circles and squawking pitifully”
-Anchovies from guts contained pseudos
-OCTOBER/NOVEMBER—DA detected on WA coast in razor clams
-Transported by currents to WA coast?
-researchers calculated that it could be possible
MESSAGE: DA APPEARED TO MOVE UP THE COAST
A bit more about what happened in 1991. In 1991, volunteers, partaking in a sea bird count, noticed large numbers of dead or dying seabirds along the beach of Monterey Bay. Once observer described them as “acting drunk, swimming in circles, and squawking horribly” In addition, they had peculiar grooming or pecking behavior.
Subsequent analyses of the stomach contents from these birds and analysis of anchovies of the bay identified domoic acid in high concentrations. It was determined that the anchovies were the vector of the toxin and that fish were feeding on a heavy bloom of the diatom Pseudo-nitzschia australis in the bay. Because of this occurrence, warnings were sent to other west coast states and British Columbia to be on the look out for possible domoic acid. By October and November, domoic acid was detected in razor clams on both the Washington and Oregon coast. However, Pseudo-nitzschia cells were not observed in the state’s coastal waters in large numbers after the razor clams tested positive for domoic acid.
Since little was known about possible transport mechanisms, it was hypothesized that the bloom had begun in California and transported up the coast to Oregon and then Washington states.