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The biometric characteristics and reproductive biology of the nereid polychaete Pseudonereis anomala were studied monthly from August 2009 to July 2010 at two ecologically different sites (Abu-Qir and El-Mex) on the Alexandria coast, south-eastern Mediterranean Sea. The maximum body length and weight showed different values at the two sites: 9.8 and 11.9 cm, and 0.77 and 1.3 g respectively. The formula of the length-weight relationship indicated allometric growth, whereas the regression equation between length to the 6th segment and weight reflected isometric growth. Immature individuals were the major component of the worm population at the two sites, making up 69.1% at Abu Qir and 66.9% at El Mex; the respective percentages of males and females at these sites were 5.8–8.1% and 22.8–27.3%. Spawning was observed all the year round with female fecundity conspicuously lower at Abu-Qir (annual average: 26556±999 eggs per female) than at El-Mex (annual average: 47 955±2916 eggs per female). However, oocyte size was greater at Abu Qir (diameter: up to 250 μm) than at El Mex (diameter: up to 220 μm).

The biochemical composition (carbohydrates, protein, lipids, fatty acids and amino acids) of the nereid polychaete Pseudonereis anomala Gravier 1901, from a shallow part of the Alexandria coast (Egypt), was studied seasonally. The results revealed that P. anomala had a lower water content, higher carbohydrates and protein, but approximately similar or higher lipid levels than several other polychaetes. Fatty acids appeared to be dominated by unsaturated acids, constituting seasonally 49.6–81%, while saturated acids reached high amounts in winter and spring (23.3 and 38.3% respectively). C20:5n-3 was the major polyunsaturated fatty acid, accompanied by small amounts of C18:4n-3, C20:4n-6, C16:1n-7 and C20:1n-9. C18:0 dominated the saturated fatty acids for most of the year, except in autumn when C16:0 was the major one.

The biometric characteristics and reproductive biology of the nereid polychaete Pseudonereis anomala were studied monthly from August 2009 to July 2010 at two ecologically different sites (Abu-Qir and El-Mex) on the Alexandria coast, south-eastern Mediterranean Sea. The maximum body length and weight showed different values at the two sites: 9.8 and 11.9 cm, and 0.77 and 1.3 g respectively. The formula of the length-weight relationship indicated allometric growth, whereas the regression equation between length to the 6th segment and weight reflected isometric growth. Immature individuals were the major component of the worm population at the two sites, making up 69.1% at Abu Qir and 66.9% at El Mex; the respective percentages of males and females at these sites were 5.8-8.1% and 22.8-27.3%. Spawning was observed all the year round with female fecundity conspicuously lower at Abu-Qir (annual average: 26556 ± 999 eggs per female) than at El-Mex (annual average: 47955 ± 2916 eggs per female). However, oocyte size was greater at Abu Qir (diameter: up to 250 µm) than at El Mex (diameter: up to 220 µm).

The Damietta coast is part of the Egyptian Mediterranean coast off the Nile Delta and has recently been polluted as a result of intensive human activities.The environmental parameters and protozoan community in the area were studied biweekly from January to December 2007. The results of the environmentalparameters indicated low salinity, oxic and anoxic conditions, high nutrient levels and intensive phytoplankton growth. A total of 69 protozoan specieswere identified, belonging to Amoebozoa (8 species), Foraminifera (12 species), non-tintinnid ciliates (22 species) and tintinnids (27 species). The numerical density of protozoans was high over the whole area, with annual averages between 8.2 × 103 cells m-3 and 51.4 × 103 cells m-3.Spring was the most productive season for protozoans, but several distinct peaks were observed during the year at the sampling sites. The protozoangroups showed clearly different spatial patterns in both composition and abundance: whereas amoebozoans and non-tintinnid ciliates were dominant in themore polluted areas (sites IV and V), tintinnids dominated in the less polluted areas (sites, I, II and III). Several pollution indicators wererecorded: amoebozoans - Centropyxis aculeata, Centropyxis sp., Cochliopodium sp.,Difflugia sp.; non-tintinnids - Bursaridium sp., Frontonia atra,Holophrya sp., Paramecium sp., Paramecium bursaria,Vasicola ciliata, Vorticella sp., Strombidium sp.; tintinnids- Favella ehrenbergii, Helicostomella subulata, Leprotintinnus nordgvisti,Tintinnopsis beroidea, Stenosemella ventricosa, Tintinnopsis campanula,T. cylindrica, T. lobiancoi, Eutintinnus lusus-undae.

Nineteen benthic polychaete species were recorded for the first time inthe intertidal zone of the Alexandria coast, south-eastern Mediterranean Sea. They belong toSyllidae (7 species), Hesionidae (3 species), Serpulidae (2 species) and7 other families (one species each). Of these species Eunice miurai Carrera-Parra& Salazar-Vallejo 1998 appears to be new to the Mediterranean Sea,while four of the alien species earlier recorded in the Mediterranean were found for thefirst time in Egyptian waters: Opisthosyllis brunnea Langerhans 1879,Loimia medusa Savigny 1822, Syllis schulzi Hartmann-Schröder1960, Phyllodoce longifrons Ben-Eliahu 1972. The newly recorded species demonstrated markedly different patterns offrequency of occurrence and numerical abundance. Spirobranchus triqueterLinnaeus 1758, S. schulzi, L. medusa and Salvatoria clavataClaparède 1863 were permanent and abundant species in fouling samples along the Alexandria coast.Saccocirrus papillocercus Bobretzky 1872 persisted in the sediments at two sites,with a much higher count at the stressed one, while Protodrilussp. inhabited sediments at two other sites throughout the year, sometimes invery high numbers. In addition, the alien species found earlier, Braniaarminii Langerhans 1881, Odontosyllis fulgurans Audouin &Milne-Edwards 1833 and O. brunnea Langerhans 1879, were frequentlyobserved along the Alexandria coast.

The purpose of the present study was to track the seasonal vertical distribution of zooplankton abundance in the epipelagic zone off Sharm El-Sheikh, Red Sea. Zooplankton samples were collected seasonally within the depth ranges of 0-25, 25-50, 50-75, 75-100 m at a single station off Sharm El-Sheikh City. The present study is a trial to expand knowledge about the structure as well as the vertical distribution of the epipelagic zooplankton community in the Gulf of Aqaba in general and in its southern part in particular. The results indicate the occurrence of 52 copepod species and several species of other planktonic groups in the study area; the zooplankton standing crop fluctuated between 1124 and 4952 organisms m-3. Copepods appeared to be the predominant component, forming an average of 86.5% of the total zooplankton count, and with other groups demonstrated a markedly different seasonal vertical distribution. Twelve bathypelagic copepod species were reported during the present study, and five species were new to the area, having migrated northwards from the main basin of the Red Sea.