Harmful Algal Information System: Event US-90-018

General Information

Event name:	US-90-018
Country:	UNITED STATES
Nature of the harmful event:	Mass mortalities
Event directly affected:
Toxicity detected:	No
Associated syndrome:	OTHER
Unexplained toxicity:	No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme:	Yes
Event occurred before in this location:	Yes (Suspected in fish kill at Lummi Island in 1976 possibly occurred in central Puget Sound in 1976 massive fish kills of salmon in net pens in northern Puget Sound, Sept. 1989.)
Individuals to contact:	HORNER, Rita

Location & Date

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Location:	Latitude: , Longitude:
General location information:	Central Puget Sound., Washington. HAB Area code(s): US-24
Additional location information:	Samish and Bellingham bays, Port Angeles Harbour, Port Townsend Bay, northern Hood Canal.
Bloom event dates (yyyy/mm/dd):	Start: 1990-07-01, End: 1990-07-14
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information:

Microalgae

Causative organism known:	Yes
Causative Species/Genus:	Heterosigma akashiwo (50,000 - 4 cells/L) Pen sites Heterosigma akashiwo (>12,000,00 cells/L) Port Angeles harbor
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known:	µg/l
Additional bloom information:
Event-related bibliography:

Environmental Conditions

Weather:	Sunny, calm 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: 17 °C, Min: 11 °C

Salinity Range During Event:

Max: 29, Min: 27

Bloom location in the water column:

Growth:

In situ

Growth Comments

In situ growth: started in sahllow back bays that warmed up quickly, then moved into more open water.

Additional Environmental information:

Secchi disk depth: 0.5 in patches - 5.3 m

Toxin Assay Information

Species containing the toxin

Toxin type

Toxin details

Max. concentration

Assay type

Kit used: No

Type of kit used:

Additional information:

Economic losses:

Management decision:

Fish growers harvested fish; two growers towed their pens to clear water after receiving contingency permits from the State Department of Fisheries.

Additional harmful effect information:

Killed Atlantic salmon in net pens in central Puget Sound; large fish (brood stock) were affected first. Also killed brood stock of White River spring chinook salmon in net pens.