Harmful Algal Information System: Event US-22-010

General Information

Event name:	US-22-010
Country:	UNITED STATES
Nature of the harmful event:	High Phyto concentration , Seafood toxins
Event directly affected:	Planktonic life , Shellfish , Humans
Toxicity detected:	Yes (Approximate range: 16-48 ppm)
Associated syndrome:	ASP
Unexplained toxicity:	No
Species implicated in toxin transmission (transvector):	Razor clam, California Mussel, and Dungeness crab viscera
Report the outcome of a monitoring programme:	Yes (California Department of Public Health - Marine Biotoxin Monitoring Program)
Event occurred before in this location:	Yes
Individuals to contact:	ZUBKOUSKY-WHITE, Vanessa

Location & Date

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Location:	Latitude: , Longitude:
General location information:	California, HAB Area code(s): US-21
Additional location information:	Locations where razor clam meat >20 ppm: Del Norte County - Crescent Beach Humboldt County- Clam Beach Dungeness crab viscera low levels of domoic acid detected (<30 ppm) in Del Norte, Humboldt, Mendocino, Sonoma, San Francisco, San Mateo, and Monterey
Bloom event dates (yyyy/mm/dd):	Event Date:2022-01-28
Quarantine levels dates (yyyy/mm/dd):	End: 2022-11-23
Additional date-related information:

Microalgae

Causative organism known:	No
Causative Species/Genus:	Pseudo-nitzschia spp. ( cells/L)
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known:	µg/l
Additional bloom information:
Event-related bibliography:

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:

Nutrient information:

Temperature Range During Event:

Max: °C, Min: °C

Salinity Range During Event:

Bloom location in the water column:

Growth:

Growth Comments

Additional Environmental information:

Toxin Assay Information

Species containing the toxin	Toxin type	Toxin details	Max. concentration	Assay type
Dungeness Crab viscera	Domoic Acid		16 �g/100g	LC
California Mussels	Domoic Acid		45 �g/100g tissue	LC
Razor Clam	Domoic Acid		48 �g/100g	LC

Kit used: No

Type of kit used:

Additional information:

Razor clams are known to store/retain domoic acid in their meat tissue at high levels long after associated pseudo-nitzschia blooms have subsided.

Economic losses:

Recreational fishery closure for razor clams was in place for a potrion of the year due to samples frequently testing above the advisory threshold.

Management decision:

Recreational fishery closure for Razor clams in place the whole year. Precautionary biotoxin closures were placed on growing area in Humboldt Bay initially, but they were allowed to remain open if testing from growing area product showed results lower tha

Additional harmful effect information:

Mass mortalities of California Sea Lions were may have be linked to DA toxicosis. Contact Mariah Tengler (tenglerm@tmmc.org) for more info.

Created at 06:05 on 5 Apr 2023
Updated at 01:58 on 6 Apr 2023