Planktonic protozoan population in the Southeastern Mediterranean off Egypt

Abundance, distribution and population structure of planktonic protozoans in the Southeastern Mediterranean off Egypt were investigated during the period from April 2008 to February 2010. Protozoan population constituted 5.4% of the total zooplankton counts. Tintinnida were the highest abundant order (average 30.4 ind.m−3 constituting about 67.1% of the total protozoan counts) followed by Foraminifera and Radiolaria. A total of 116 protozoan species were identified, out of them 86 tintinnids, 15 foraminifers and 15 radiolarians. Among them, 56 species are new records in the Egyptian water. Temporal distribution of protozoan abundance indicated that they flourished during the cold months (the highest mean value, 90.3 ind.m−3 was recorded during winter). There was a decrease in abundance towards the offshore where the annual averages in the three depth zones; inshore, middle and offshore were 59, 44.3 and 32.6 ind.m−3 respectively, except at Fouka section where protozoan abundance decreased westwards. Generally, it would be concluded that, planktonic protozoan population in the investigated area is low in abundance but is highly diversified.