General Information

Event name: US-00-006
Nature of the harmful event:
High Phyto concentration , Seafood toxins , Mass mortalities
Event directly affected:
Natural Fish , Aquatic Mammals
Toxicity detected: Yes (Approximate range: 1 - 29 ppm DA in mussels; 130 ppm DA in sardines; 50 ppm in anchovies.)
Associated syndrome: ASP
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (California Department of Health Services Marine Biotoxin Monitoring Program.)
Event occurred before in this location: Yes (Blooms of Pseudo-nitzschia spp. have been documented along the California coast, especially in the San Luis Obispo and Monterey area, since 1991.)
Individuals to contact: LANGLOIS, Gregg , LOSCUTOFF, Susan

Location & Date

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Location: Latitude: , Longitude:
General location information: Sanluis Obispo to Monterey Bay., California.
HAB Area code(s): US-20
Additional location information: Central California.
Bloom event dates (yyyy/mm/dd): Start: 2000-06-07, End: 2000-09-16
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: 7/6/2000 (mussels); 9/16/2000 (sardines).


Causative organism known: Yes
Causative Species/Genus: Pseudo-nitzschia australis ( cells/L)
Abundant at several sites along the San Luis Obispo and Santa Barbara coast by beginning of July. By August also abundant in Monterey and farther north in Humboldt Bay. Pattern continued through September except in Santa Barbara, where relative abundance
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: Co-ocurring dominant species: mix of diatoms and dinoflagellates with no other dominant species. By August the San Luis Obispo coast was experiencing increased numbers of Gonyaulax polyedra.
Event-related bibliography: Documented in our program's monthly/quarterly reports.

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: No Oxygen content (nL/L): Wind velocity:
Temperature (°C): Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: Current Velocity: 0
Nutrient information:
Temperature Range During Event: Max: °C, Min: °C
Salinity Range During Event:
Bloom location in the water column:
Growth Comments
Additional Environmental information: Sea surface temperature data being processed for the duration of this event.

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Anchovies Domoic Acid DA eq 50 ppm LC
Mytilus californianus Domoic Acid DA eq 29 ppm LC
Sardines Domoic Acid DA eq 130 ppm LC
Kit used: Type of kit used:
Additional information: The detection of 29 ppm DA in mussels was the highest concentration we have observed since the first documented DA event in California in 1991.
Economic losses:
Management decision: Health Advisories issued for San Luis Obispo County and Monterey Bay: alerted public to avoid eating any bivalve shellfish from these areas, as well as anhovies, sardines, and Dungeness and rock crab viscera.
Additional harmful effect information: Significant impact to marine mammals, principally California sea lions, throughout this region.
Updated at 01:15 on 10 Oct 2020