General Information

Event name: US-16-027
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: Yes (VIMS HAB Monitoring Program)
Event occurred before in this location: Yes
Individuals to contact: REECE, kimberly

Location & Date

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Location: Latitude: , Longitude:
General location information: York River, Chesapeake Bay
HAB Area code(s): US-10
Additional location information: York River from Chesapeake Bay to the Naval Weapon Station. first seen at blooom levels (>1,000,000 cells/L) July 31, 2016; last seen at bloom levels August 16, 2016
Bloom event dates (yyyy/mm/dd): Start: 2016-07-31, End: 2016-08-16
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information:


Causative organism known: Yes
Causative Species/Genus: Cochlodinium polykrikoides (9,899,000 cells/L)
Co-Ocurring Species/Genus: Alexandrium monilatum (233,000 cells/L)
Chlorophyll concentration, if known: µg/l
Additional bloom information: Prorocentrum minimum (Dinophyceae) was co-occurring at the start of the bloom at 57,000 cells/L changing over to low levels of A. monilatum towards the end of the C. polykrikoides bloom
Event-related bibliography:

Environmental Conditions

Weather: Turbidity (NTU): Wind direction:
Stratified water: Oxygen content (nL/L): 15.6 Wind velocity:
Temperature (°C): 31.6 Oxygen saturation %: Current Direction:
Sechhi disk (m): Salinity: 18.2 Current Velocity:
Nutrient information:
Temperature Range During Event: Max: 32 °C, Min: 28 °C
Salinity Range During Event: Max: 22, Min: 18
Bloom location in the water column:
In situ
Growth Comments
Additional Environmental information: pH 8.73; uncorrected CHLa 536.6 ug/L for the bloom sample data listed above from 8/15/16

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: Larval oyster mortality; loss of approximately 50% of the stock for one grower.
Management decision:
Additional harmful effect information:
Created at 06:11 on 23 Mar 2017