A very intense bloom was observed in the
southeastern Black Sea between 18 to 20 April 2011.
Table 1 shows a resume of other intense blooms in
different geographical regions. The cell numbers
reported in this study (6.81 x 106 cells l-1) were within the range (105-108 cells/l) of red-tides in other regions
(Table 1), but higher than previous studies reported in
the Black Sea (Porumb, 1989; Harrison et al., 2011;
Mikaelyan et al., 2014).