Abdulsalam Alkawri

As a part of an annual analysis on the phytoplankton distribution and composition, regular monthly sampling carried out during October 2007- September 2008 from salinity gradient zones in the intertidal waters along the coast of Goa. Among the 179 species of phytoplankton observed during this study, as many as 11 of them are recognized, potentially toxic ones. The toxic diatom species, Pseudo-nitzschia pungens was quite preponderant, in particular during the pre-monsoon month of May 2008 off Chapora, a perennially low salinity location. Among the 10 toxic dinoflagellate species detected, the known toxic species, Alexandrium minutum followed by Dinophysis acuminata were found to attain maximum cell numbers in the study area. It is apparent from our results that the toxic species do occur in all salinity zones sampled and during many months of the year in coastal waters off Goa. Though directly governed by the variations in nutrient concentrations, some of these toxic phytoplankton sp...

As a part of an ongoing monitoring study of phytoplankton in Yemeni coastal waters, phytoplankton samples were collected from November 2012 to September 2013 at four sampling locations along the coast of Hodeida City, southern Red Sea. A bloom of toxic dinoflagellate Pyrodinium bahamense var. bahamense Plate was observed in August 2013. The population density of P. bahamense were ranged from 1.6 × 10 to 3.3 × 10 cell L (accounting for 41.8 % of the overall phytoplankton community). This finding is the first observation of vegetative cells of this tropical species from the Red Sea. Water temperatures during the bloom was 32°C and salinity was 37 psu, indicating its tropical and subtropical nature. Among the phytoplankton species reported during this study, the red tide-forming species; Trichodesmium erythraeum (14.1%), Protoperidinium quinquecorne (6.3 %) and the known toxic species, Dinophysis caudata (1.4 %), and D. acuminata (1.00 %) were remarkable. It is apparent from our result...

General abundance and species composition of a dinoflagellate community in Yemeni coastal waters of Al Salif (southern Red Sea) were studied with a view to understand the annual variations in particular the toxic species. Dinoflagellates were more abundant among phytoplankton. Thirty five dinoflagellate taxa were identified, among which 12 were reported as potentially toxic species. A significant change in seasonal abundance was recorded with the maximum (2.27∗10(6)cellsl(-1)) in May, and the minimum (2.50∗10(2)cellsl(-1)) recorded in January. Kryptoperidinium foliaceum, which was reported for the first time from the Red Sea, was the most abundant species with a maximum in May 2013 (2.26∗10(6)cellsl(-1)). Spearman's rank correlation analysis indicates that, total harmful dinoflagellate cells, K. foliaceum, Prorocentrum gracile and Prorocentrum micans were significantly correlated with temperature. This study suggests that Yemeni waters should be monitored to investigate harmful species and to identify areas and seasons at higher risk.

As part of an ongoing monitoring study of phytoplankton in Yemeni coastal waters we report, for the first time, a dense bloom (14.310 6 cell L −1) of the marine dinoflagellate species Protoperidinium quinquecorne (Abé) Balech on June 6, 2012 from the coastal water of Al Hodeidah and Khor Al-Khateeb lagoon, southern Red Sea. Water temperature was 34°C and salinity was 36 during the bloom, indicating its tropical and subtropical nature. This bloom was accompanied by a massive kill of small pelagic fish, which were mostly sardines. Among the phytoplankton species reported during the P. quinquecorne bloom, the red tide-forming species, Trichodesmium erythraeum (cyanobacteria), Gonyaulax verior, and Prorocentrum micans, and the known toxic species, Dinophysis acuminata, were notable.

As part of an ongoing monitoring study of phytoplankton in Yemeni coastal waters, phytoplankton samples were
collected from November 2012 to September 2013 at four sampling locations along the coast of Hodeida City,
southern Red Sea. A bloom of toxic dinoflagellate Pyrodinium bahamense var. bahamense Plate was observed in
August 2013. The population density of P. bahamense were ranged from 1.6 × 104 to 3.3 × 105 cell L-1
(accounting
for 41.8 % of the overall phytoplankton community). This finding is the first observation of vegetative cells of this
tropical species from the Red Sea. Water temperatures during the bloom was 32°C and salinity was 37 psu,
indicating its tropical and subtropical nature. Among the phytoplankton species reported during this study, the red
tide-forming species; Trichodesmium erythraeum (14.1%), Protoperidinium quinquecorne (6.3 %) and the known
toxic species, Dinophysis caudata (1.4 %), and D. acuminata (1.00 %) were remarkable. It is apparent from our
results that the toxic species do occur during many months of the year in the Coastal Waters of Yemen with high
abundance observed in August followed by April 2013. Further studies are required to carry out the HAB
monitoring for preventing the risk of HAB events that may outbreak in future at the Red Sea coast.

General abundance and species composition of dinoflagellate community in different salinity gradients along thecoastofGoa (west coast of India) were studiedwith aview to understandtheannual variations in particular the toxic species. Regular monthly samples were collected from the inter-tidal regions for elucidatingtheeffectofphysicalandchemicalparametersondinoflagellateassemblageatfourdisparate locations in terms of their salinity. From this 13-month study, a total number of 25 dinoflagellate species were identified. Of these, 10 are known toxic species. Ceratium furca was the most dominant dinoflagellate species at all four sampling locations throughout the year. Its highest number, 5763 cells l1, was observed during September 2008 at the estuarine sampling location off Siridao. The toxic species, Alexandrium minutum (1171 cells l1) followed by Dinophysis acuminata (838 cells l1) were found to attain maximum cell numbers among the 10 different toxic species detected from the study area. It is apparent from our results that the distribution of both general and toxic dinoflagellate species in the study area is affected due to variations in physico-chemical parameters, in particular temperature, salinity and nitrate that in turn are governed by the monsoonal dynamics.