In the W.H. quite a unique situation was observed in spring
at all stations, this was the presence of a potentially harmful
bloom of euglenoid flagellates Eutreptiella. More than 80% of
the phytoplankton cell counts corresponded to Eutreptiella,
except in station 5 (51.0%). On this occasion, minimum
concentrations of Eutreptiella had already been detected
in station 5, from which salinity recorded maximum value
(34.2 PSU) and co-occurred with minimum of nutrient salt
concentrations. During the days prior to event, gusty winds
occurred, with a temperature range of 24.1—25.68C and
salinity range of 22.7—34.2 PSU, as well as green sea water
discoloration. Eutreptiella sp. bloom reached a maximum
concentration of 66 106 cells l
1 at station 6, with 99.8%
dominance and no human health effects or intoxication was
associated with this event, i.e., no fish death was observed.
The genus comprises nine known species