Harmful Algal Information System: Event US-96-009

General Information

Event name:	US-96-009
Country:	UNITED STATES
Nature of the harmful event:	Water Discoloration , Mass mortalities
Event directly affected:	Humans
Toxicity detected:	Yes (Approximate range: 200-260 MU. (Brevetoxin))
Associated syndrome:	NSP , Aerosolized toxins effects
Unexplained toxicity:	No
Species implicated in toxin transmission (transvector):
Report the outcome of a monitoring programme:	Yes
Event occurred before in this location:	Yes (Red Tide: Previously occurred in 1986.)
Individuals to contact:	STOCKWELL, Dean A.

Location & Date

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Location:	Latitude: , Longitude:
General location information:	Matagorda Bay to Port Isabel., Texas. HAB Area code(s): US-18
Additional location information:	Red Tide: Coastal texas - Matagorda Bay to Port Isabel (this includes San Antonio, Aransas, Matagorda and Corpus Christi Bays).
Bloom event dates (yyyy/mm/dd):	Start: 1996-09-11, End: 1996-10-20
Quarantine levels dates (yyyy/mm/dd):
Additional date-related information:

Microalgae

Causative organism known:	Yes
Causative Species/Genus:	Gymnodinium breve (300,000,00 cells/L)
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:	No	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: 27 °C, Min: 21 °C

Salinity Range During Event:

Max: 42, Min: 25

Bloom location in the water column:

Growth:

Advected
In situ

Growth Comments

Initial population advected into nearshore waters, with in situ growth occurring in coastal embayments.

Additional Environmental information:

Occurred in nearshore and shelf waters and in coastal embayments and lagoons.

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:

Red Tide: Shellfish harves bans due to Gymnodinium breve red tide - Matagorda Bay south to Texas-Mexico border. Bays closed from September 1996 - February 1997.

Additional harmful effect information:

Red Tide: Dead fish (approximately 5 million) - inshore and offshore within coastal lagoons. Water discoloration brownish-red. Respiratory irritation throughout the entire area. Noted oyster die-offs in areas of high concentrations.

Updated at 03:09 on 14 May 2018