General Information

Event name: US-07-001
Nature of the harmful event:
High Phyto concentration , Seafood toxins , Mass mortalities
Event directly affected:
Natural Fish , Shellfish , Aquatic Mammals
Toxicity detected: Yes (Approximate range: 1 - 169 ug/g tissue)
Associated syndrome: ASP
Unexplained toxicity:
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (California Department of Public Health Marine Biotoxin Monitoring Program)
Event occurred before in this location: Yes (Early spring/early summer event in central/southern California typical over the past several years)
Individuals to contact: LANGLOIS, Gregg

Location & Date

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Location: Latitude: , Longitude:
General location information: California, South Coast, Central Coast, Northern Coast
HAB Area code(s): US-19 US-20 US-21
Additional location information: 1, 3, 4. Santa Barbara, Ventura, Los Angeles counties (19): South of Pt. Conception. 2. San Luis Obispo County (20)
Bloom event dates (yyyy/mm/dd): Start: 2007-03-03, End: 2007-04-01
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: 1. Santa Barbara County: First detection of DA on March 15 following observed increase in Pseudo-nitzschia on March 5. Alert level exceeded by April 11 (62 ppm), with maximum measured concentration of 610 ppm reached by April 24 (A new CA record for DA levels in mussels). DA levels in mussels did not decline below the alert level until May 15. Low levels of DA persisted through the end of May. Elevate DA concentrations also detected in aquacultured Pacific oysters (59 ppm, Santa Barbara), brown rock crab viscera (110 ppm, Santa Rosa Island) and spiny lobster viscera (136 ppm, Santa Cruz Island). 2. Synchronous with the SB event, low concentration of DA detected on March 20, exceeded the alert level by April 4. Maximum concentration was 30 ppm on April 20, declining below alert level by April 25. 3. Ventura County: Continuation of SB event, DA exceeded alert level by April 19 (237 ppm). Declined below alert level by May 8. 4. LA County: Continuation of SB-Ventura pattern. Brief increase above alert level by April 27 (26 ppm), decreasing by May.


Causative organism known: Yes
Causative Species/Genus: Pseudo-nitzschia spp. ( cells/L)
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: 1-4. Santa Barbara/SLO/Ventura/LA Counties: Samples from volunteer monitoring network caught dramatic increase in Pseudo-nitzschia at Pismo Pier (SLO, March 3) and at Ellwood Pier (SB, March 6). Cell numbers continued to increase through April. Southwar
Event-related bibliography: Monthly/Annual reports issued by CDHS Marine Biotoxin Monitoring Program.

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: 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:

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Mytilus californianus Domoic Acid 23 ppm LC
Kit used: Yes Type of kit used: Jellet rapid extraction kit us
Additional information: HPLC
Economic losses:
Management decision: Harvest closures in commercial aquaculture areas; Health Advisory for sportharvested shellfish and viscera of sardine, anchovy, crab and lobster in Southern California.
Additional harmful effect information:
Updated at 01:18 on 10 Oct 2020