General Information

Event name: NO-93-001
Country: NORWAY
Nature of the harmful event:
Mass mortalities
Event directly affected:
Aquaculture Fish
Toxicity detected: Yes
Associated syndrome:
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes
Event occurred before in this location: Yes (Bloom occurred in 1989, 1990, 1991 and 1992.)
Individuals to contact: DAHL, Einar , MARTINUSSEN, Ingrid

Location & Date

[View larger map]
Location: Latitude: , Longitude:
General location information: Ryfylkefjordene (near Stavanger)., SOUTH WEST COAST.
HAB Area code(s): NO-09
Additional location information:
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: Late June - August.


Causative organism known: Yes
Causative Species/Genus: Prymnesium sp. (2,500,000 cells/L)
Prymnesium cf. Parvum
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information:
Event-related bibliography:

Environmental Conditions

Weather: Turbidity (NTU): 4.5-6 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: 15 °C, Min: 10 °C
Salinity Range During Event:
Bloom location in the water column:
Growth Comments The bloom was first located in the inner parts of the fjord system. Some advection of algae and especially toxic flakes are observed throughout the fjord system.
Additional Environmental information: In the most intensive blooms period the temperature range 13-15 C.

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: Fish farms in the danger zones escaped the area.
Additional harmful effect information: To verify toxicity of the algae, test-cages of salmon were placed on different locations in the fjord-system. To detect floating toxic flakes an open well-boat with salmon was tracked in the fjord system. When entering toxic water the fish biked over. Mos
Updated at 02:35 on 5 Mar 2018