Harmful Algal Information System: Event CA-91-007

General Information

Event name:	CA-91-007
Country:	CANADA
Nature of the harmful event:	Seafood toxins
Event directly affected:
Toxicity detected:	Yes (Approximate range: 29 痢/g DA.)
Associated syndrome:	ASP
Unexplained toxicity:	No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme:	Yes
Event occurred before in this location:	Yes (Nitzschia pungens and low levels of domoic acid have been detected in New London Bay since 1988, but this is the first year that the bay was closed to harvesting due to domoic acid contamination.)
Individuals to contact:	SMITH, John C.

Location & Date

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Location:	Latitude: , Longitude:
General location information:	Eastern Prince Edward Island, Gulf Region HAB Area code(s): CA-24
Additional location information:	New London Bay
Bloom event dates (yyyy/mm/dd):	Event Date:1991-09-27
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information:	Mid-September to mid-October.

Microalgae

Causative organism known:	Yes
Causative Species/Genus:	Nitzschia pungens f. multiseries (800,000 cells/L) near the peak of the bloom.
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:	27	Current Velocity:	0

Nutrient information:

Temperature Range During Event:

Max: 16 °C, Min: 9 °C

Salinity Range During Event:

Bloom location in the water column:

Growth:

Advected
In situ

Growth Comments

Most probably, the population originated within New London Bay.

Additional Environmental information:

The water column was well mixed.

Toxin Assay Information

Species containing the toxin	Toxin type	Toxin details	Max. concentration	Assay type
Mytilus edulis (Sept 28)	Domoic Acid	DA eq	29 痢/g	Bioassay-Mouse
Mytilus edulis (Sept 27)	Domoic Acid	DA eq	17 痢/g	Bioassay-Mouse
Crassostrea virginica	Domoic Acid	DA eq	generally < 5 痢/g ,	LC

Kit used:

Type of kit used:

Additional information:

Economic losses:

Management decision:

Because levels exceeded the federal limit of 20 痢/g, New London Bay was closed to the harvesting of molluscan shellfish from September 30 to October 31.

Additional harmful effect information:

Updated at 07:10 on 25 Sep 2013