General Information

Event name: NO-90-003
Country: NORWAY
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 (Gyrodinium bloomed in the area in 1966, 1976, 1981, 1982, 1985, 1988.)
Individuals to contact: DAHL, Einar

Location & Date

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Location: Latitude: , Longitude:
General location information: , SOUTHERN AND SOUTHWESTERN COAST
HAB Area code(s): NO-09 NO-10 NO-11
Additional location information:
Bloom event dates (yyyy/mm/dd): Start: 1990-08-01, End: 1990-08-31
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: August


Causative organism known: Yes
Causative Species/Genus: Gyrodinium sp. (20,000,000 cells/L)
Gyrodinium cf. Aureolum.
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: But normally the recordings were from some hundred thousands to a few million cells per litre.
Event-related bibliography:

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: 18 °C, Min: 13 °C
Salinity Range During Event: Max: 34, Min: 30
Bloom location in the water column:
Growth: Advected
In situ
Growth Comments The bloom was due to a combination of advected populations and in situ growth.
Additional Environmental information: The water column had a high stability although not as high as observed during the most dense surface blooms observed in earlier years.

Toxin Assay Information

Species containing the toxin Toxin type Toxin details Max. concentration Assay type
Kit used: Type of kit used:
Additional information:
Economic losses:
Management decision: Intensified local algae monitoring. Deep cages did probably save most of the farms in the area from large losses.
Additional harmful effect information:
Updated at 04:02 on 2 Dec 2019