General Information

Event name: US-99-006
Nature of the harmful event:
High Phyto concentration , Other ( Sporadic high level of domoic acid in plankton in 1997-1998 (up to 29 pg/cel 1 Pseudo-nitzschia), toxin analyses not yet complete for 1999 but no reas)
Event directly affected:
Toxicity detected: No
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 (Since monitoring began in 1990.)
Individuals to contact: DORTCH, Quay

Location & Date

[View larger map]
Location: Latitude: , Longitude:
General location information: Estuarine and Coastal Water of Mississippi Ri, Lousiana.
HAB Area code(s): US-17
Additional location information: Includes estuarine and coastal waters east and west of the Mississippi River.
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: All of 1999.


Causative organism known: Yes
Causative Species/Genus: Pseudo-nitzschia spp. ((10)7 cells/L)
Up to (10)7 cells/liter and 30% of samples
Pseudo-nitzschia multiseries ( cells/L)
Pseudo-nitzschia delicatissima ( cells/L)
Pseudo-nitzschia pseudodelicatissima ( cells/L)
Pseudo-nitzschia pungens ( cells/L)
Pseudo-nitzschia subfraudulenta ( cells/L)
Pseudo-nitzschia sp. ( cells/L)
Pseudo-nitzschia cf. Americana
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: Pseudo-nitzschia spp. Including: Multiseries, delicatissima, pseudodelicatissima, pungens, subfraudulenta, cf american and several unknown species.
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: °C, Min: °C
Salinity Range During Event:
Bloom location in the water column:
Growth Comments
Additional Environmental information:

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:
Additional harmful effect information: