General Information

Event name: US-05-012
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.)
Individuals to contact: RABALAIS, Nancy

Location & Date

[View larger map]
Location: Latitude: , Longitude:
General location information: Louisiana, Bayou des Allemands, Bayou Chevreiul
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 the Barataria Basin. Bayou Chevreiul 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 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 5/23/05 to 8/23/05.


Causative organism known: Yes
Causative Species/Genus: Anabaena spp. (5.05x10^8 cells/L)
Raphidiopsis spp. (2.42x10^7 cells/L)
Planktolyngbya contorta (2.78x10^7 cells/L)
Co-Ocurring Species/Genus: Microcystis sp. (n/a cells/L)
Microcystis sp. was present in huge numbers at most of these events, but due to the nature of that colonial species, reliable enumeration is difficult.
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: