General Information

Event name: US-06-007
Nature of the harmful event:
Water Discoloration , High Phyto concentration
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 (This area frequently sees high concentrations of the species listed in section 3 below)
Individuals to contact: RABALAIS, Nancy

Location & Date

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Location: Latitude: , Longitude:
General location information: Bayou des Allemands, Bayou Chevreil, Louisiana
HAB Area code(s): US-17
Additional location information: Bayou des Allemands is a long narrow bayou that connects Lake Salvador and Lac des Allemands, two low salinity lakes in the upper part of hte Barataria Basin. Bayou Chevreil is a small bayou that drains into Lac des Allemands.
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: This summer and into fall our field personnel were reporting visible blooms regularly in this area as they collected routine data for various projects. Species data were enumerated from surface water samples collected from 7/13/06 to 10/10/06. The locations from which these samples were collected are not part of LUMCON's regular phytoplankton enumeration sites and thus are not duplicated elsewhere in these reports. Rather, their collection is prompted by something unusual noted by the field personnel. Cell concentrations are averaged where multiple locations were sampled on a single date.


Causative organism known: Yes
Causative Species/Genus: Raphidiopsis curvata (2.74x10^5 cells/L)
upper Bayou des Allemands, 7/13/06
Raphidiopsis curvata (1.87x10^6 cells/L)
upper Bayou des Allemands, 7/19/06
Raphidiopsis curvata (5.86x10^6 cells/L)
Lac des allemands and B. Chevreil, 10/10/06
Cylindrospermopsis raciborskii (1.61x10^7 cells/L)
Lac des allemands and B. Chevreil, 10/10/06
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: 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: Type of kit used:
Additional information:
Economic losses:
Management decision:
Additional harmful effect information: