General Information

Event name: US-11-020
Nature of the harmful event:
Water Discoloration , High Phyto concentration
Event directly affected:
Planktonic life
Toxicity detected: No
Associated syndrome:
Unexplained toxicity: No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme: Yes (Chesapeake Bay Monitoring Program)
Event occurred before in this location: Yes
Individuals to contact: MARSHALL, Harold G.

Location & Date

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Location: Latitude: , Longitude: -76.567222
General location information: Elizabeth River, Norfolk, Virginia, Chesapeake Bay
HAB Area code(s): US-10
Additional location information: Generally very extensive, spreading to various inlets and bays. Blooms of this species occur annually in this river and its tributary the Lafayette River, generally lasting into early fall months. These blooms also enter the lower James River
Bloom event dates (yyyy/mm/dd):
Quarantine levels dates (yyyy/mm/dd): First detection: 2011-07-15, End: 2011-08-05
Additional date-related information: Blooms often extend into the lower Chesapeake


Causative organism known: Yes
Causative Species/Genus: Cochlodinium polykrikoides (5,000,000 cells/L)
typically 400,000-500,000 cells / L
Co-Ocurring Species/Genus:
Chlorophyll concentration, if known: µg/l
Additional bloom information: decomposition accompanied by odors, reduced oxygen levels
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: °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:
Checked at 05:06 on 15 Apr 2015