General Information

Event name: US-05-013
Nature of the harmful event:
Water Discoloration , High Phyto concentration
Event directly affected:
Toxicity detected: Yes (Approximate range: 0.578ug/l microcystin)
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

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Location: Latitude: , Longitude:
General location information: Lake Salvador, Louisiana,
HAB Area code(s): US-17
Additional location information: Low salinity lake in the upper part of the Barataria Basin
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information: The thickest part of the bloom was in the center of the lake, but extended south and west into adjoining bayous. The bloom was first detected by our field personnel on 4/27/05, where a preserved sample was taken for enumeration of species, but no water was collected for toxin analysis until the following week on 5/3/05. Species levels were still high at this time, but lower than the previous week.


Causative organism known: Yes
Causative Species/Genus: Anabaena spp. (4.46x10^8 cells/L)
Anabaena spp. (9.10x10^7 cells/L)
Co-Ocurring Species/Genus: Microcystis sp. (n/a cells/L)
Hard to quantify
Aphanizomenon sp. (1.98x10^7 cells/L)
Planktolyngbya contorta (5.47x10^7 cells/L)
Planktolyngbya sp. (9.95x10^6 cells/L)
Chlorophyll concentration, if known: µg/l
Additional bloom information: On site there was a pungent odor associated with the bloom which resulted in a slight burning sensation in the nostrils after prolonged exposure; one field member also experienced a serious headache and gastrointestinal problems shortly after sampling was
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: