| Event name: | ZAF-97-002 | |
| Country: | SOUTH AFRICA | |
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Nature of the harmful event: |
Water Discoloration , High Phyto concentration | |
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Event directly affected: |
Shellfish | |
| Toxicity detected: | No | |
| Associated syndrome: | OTHER | |
| Unexplained toxicity: | ||
| Species implicated in toxin transmission (transvector): | ||
| Report the outcome of a monitoring programme: | No | |
| Event occurred before in this location: | No | |
| Individuals to contact: | MANSFIELD, Lisa | |
| Location: | Latitude: -33.007500, Longitude: 18.004722 | |
| General location information: |
Saldanha Bay, West Coast HAB Area code(s): ZAF-01 |
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| Additional location information: | Occurred in a tidal dam, the site of and oyster farm | |
| Bloom event dates (yyyy/mm/dd): |
Event Date:1997-02-01 Start: 1997-02-01, End: 1997-03-31 |
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| Quarantine levels dates (yyyy/mm/dd): | ||
| Additional date-related information: | Actual dates of the bloom were not published | |
| Causative organism known: | Yes | |
| Causative Species/Genus: |
Aureococcus anophagefferens
(1-3x10e9 cells/L)
|
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| Co-Ocurring Species/Genus: | ||
| Chlorophyll concentration, if known: | 21-41 µg/l | |
| Additional bloom information: | First occurrence of brown tide organism, Aureococcus anophagefferens. | |
| Event-related bibliography: | PROBYN, T.A., G.C. PITCHER, R.N. PIENAAR and R. NUZZI 2001 – Brown tides and mariculture in Saldanha Bay, South Africa. Mar. Poll. Bull. 42(5): 405-408. | |
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| Nutrient information: | ||||||||||||||||||||||||||
| Temperature Range During Event: | Max: °C, Min: °C | |||||||||||||||||||||||||
| Salinity Range During Event: | ||||||||||||||||||||||||||
| Bloom location in the water column: |
Whole column
Surface Subsurface |
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| Growth: | ||||||||||||||||||||||||||
| Growth Comments | ||||||||||||||||||||||||||
| Additional Environmental information: | the morphology of the bay and the nature of exchange with coastal waters do provide a favourable environment for Aureococcus blooms under certain conditions. | |||||||||||||||||||||||||
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| Kit used: | Type of kit used: | ||||||
| Additional information: | |||||||
| Economic losses: | Following the appearance of Aureococcus in 1997, harvests of oysters declined considerably (from approx. >50000 to <10000 oysters per month).The bay-wide bloom in 1998 also had a negative effect on mussel farmers in Small Bay. | ||||||
| Management decision: | As a direct result of the brown tide related fall in oyster production the farm was placed in preliminary liquidation in April 1999. | ||||||
| Additional harmful effect information: | Should bay-wide blooms of Aureococcus become a more frequent, albeit seasonal, feature of the system, they could have dire consequences for the shellfish industry in this important mariculture development area. | ||||||
