General Information

Event name: PT-88-004
Nature of the harmful event:
Water Discoloration
Event directly affected:
Toxicity detected: No
Associated syndrome:
Unexplained toxicity:
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: No
Event occurred before in this location: Yes (Csesis Bay 1982; Albufeira Lagoon 1987; mariculture ponds at Ria Formosa Lagoon (Alvarve coast) 1987)
Individuals to contact: SAMPAYO, MĒ Antonia

Location & Date

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Location: Latitude: , Longitude:
General location information: Sao Martinho do Porto Bay,
HAB Area code(s): PT-01
Additional location information:
Bloom event dates (yyyy/mm/dd): Start: 1988-08-03, End: 1988-08-10
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information:


Causative organism known: Yes
Causative Species/Genus: Heterosigma akashiwo (9.7x10(6) cells/L)
Co-Ocurring Species/Genus: Skeletonema costatum (2x10(6) cells/L)
Small flagellates 3.7x10(6); Dinoflagellates 0.2 x 10(6)
Chlorophyll concentration, if known: µg/l
Additional bloom information: Heterosigma akashiwo has been associated with fish kills in other countries, in the Portuguese case only in the mariculture ponds at Algarve 1987 there was some mortality, this may be attributed to the confinment of the animals in the ponds
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: 18 °C, Min: 16 °C
Salinity Range During Event: Max: 35.5, Min: 34
Bloom location in the water column:
Growth: Advected
Growth Comments Probably advected from offshore and concentrated inside the Bay associated with some in situ growth
Additional Environmental information: Intense brown discolorations

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:
Additional harmful effect information: Oxygen deficiency observed at several localities in the early morning. Fish kills: none.
Checked at 05:32 on 22 Feb 2018