| Event name: | ZAF-07-001 | |
| Country: | SOUTH AFRICA | |
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Nature of the harmful event: |
High Phyto concentration | |
|
Event directly affected: |
Shellfish | |
| Toxicity detected: | Yes (Approximate range: 0.5 - 11.7 mg STX eq kg-1) | |
| Associated syndrome: | PSP | |
| Unexplained toxicity: | No | |
| Species implicated in toxin transmission (transvector): | ||
| Report the outcome of a monitoring programme: | No | |
| Event occurred before in this location: | ||
| Individuals to contact: | MANSFIELD, Lisa | |
| Location: | Latitude: -32.039167, Longitude: 18.260000 | |
| General location information: |
Lamberts Bay, West Coast HAB Area code(s): ZAF-01 |
|
| Additional location information: | Mooring station 3.5km offshore of Lambert's Bay, within the St Helena Bay region. | |
| Bloom event dates (yyyy/mm/dd): | Start: 2007-03-20, End: 2007-04-11 | |
| Quarantine levels dates (yyyy/mm/dd): | ||
| Additional date-related information: | 20 March-11 April -2 upwelling periods occur | |
| Causative organism known: | Yes | |
| Causative Species/Genus: |
Alexandrium catenella
(6.1x10e5 cells/L)
at 5m on 22 March |
|
| Co-Ocurring Species/Genus: |
Dinophysis acuminata
(8.3x10e4 cells/L)
at 5m on 25 March Pseudo-nitzschia spp. (1.2x10e6 cells/L) at 5m on 29 March |
|
| Chlorophyll concentration, if known: | 38 - 63 µg/l | |
| Additional bloom information: | An increase in phytoplankton biomass was associated with the onset of each period of downwelling, depicted by subsurface chlorophyll-a maxima of 38µg/L (on 22 March) 63µg/L (on 29 March). The extended period of stratification during the later stages of the study, from 3 to 11 April, was distinguished by low phytoplankton biomass depicted by chlorophyll-a concentrations less than 5µg/L. | |
| Event-related bibliography: | HUBBART, B., PITCHER, G.C., KROCK, B. and A.D. CEMBELLA 2012 – Toxigenic phytoplankton and concomitant toxicity in the mussel Choromytilus meridionalis off the west coast of South Africa. Harmful Algae, 20: 30-41. | |
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| Nutrient information: | ||||||||||||||||||||||||||
| Temperature Range During Event: | Max: 16.5 °C, Min: 10.5 °C | |||||||||||||||||||||||||
| Salinity Range During Event: | ||||||||||||||||||||||||||
| Bloom location in the water column: |
Surface Subsurface |
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| Growth: | Advected | |||||||||||||||||||||||||
| Growth Comments | ||||||||||||||||||||||||||
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| Kit used: | Type of kit used: | |||||||||||
| Additional information: | Four different assays were carried out (LC-FD, ELISA, RBA and MBA) to test for PSP. Results and bias are compared in this study. | |||||||||||
| Economic losses: | ||||||||||||
| Management decision: | ||||||||||||
| Additional harmful effect information: | ||||||||||||
