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The reproductive biology of the commercial seabait polychaete species Perinereis nuntia brevicirris, Lumbrineris funchalensis and Halla parthenopeia was investigated from samples obtained from the Suez Canal, Egypt, to determine sex-ratio, reproductive maturity stages, spawning season, and fecundity. Samples were collected monthly from January 2002 to February 2003. The results of sex-ratio indicated that males of the three studied worms outnumbered females through the whole study period. Based upon histological features of the coelomic contents, four maturity stages were described in females of P. nuntia brevicirris, three stages were described for females of L. funchalensis and three stages for females of H. parthenopeia. The spawning season of P. nuntia brevicirris was found to take place during spring and L. funchalensis does not have a defined breeding season, while H. parthenopeia has two reproductive periods, one in May and the second in November and lasted to January. Fecundity was estimated by counting the number of oocytes per each female-it showed that P. nuntia brevicirris is more fecund (mean ¼ 208.358 +2080 oocyte/female) than L. fanchalensis and H. parthenopeia (mean ¼ 2660 +654 and 142,068 +2005 oocyte/female respectively). This study is the first to document aspects of the reproductive biology of the highly commercial polychaetes in the Suez Canal and adds to our knowledge for understanding their reproductive patterns and strategies.

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In the current work, the overall ratio between males and females of Sarpa salpa was 1:0.32. The first sexual maturity of males was recorded at length group (21.1-24cm) by 66.6% and the female was recorded at length group (24.1-27) by 50%. Ovaries of S. salpa were examined. The smallest mature female had a total body length of 29 cm and 387.73 gm weight with absolute fecundity of 2,978,440 eggs. The largest female had total body length of 39 cm and body weight of 918.86 gm with absolute fecundity 1,685,729 eggs. Based on the results of maturity stages, gonadosomatic indices (G.S.I) and ova diameters, the study showed clearly that spawning season of S. salpa in the Libyan coast of the Mediterranean waters extends from October to December.

Dolphins were photographed for individual identification purposes in Samadai reef, Marsa Alam, Red Sea between January 2012 and March 2013. In this study, 255 spinner dolphin Stenella longirostris were identified with a mean identification rate of 45%. Photo-identification analysis provided a population size range of 567 to 637 for spinner dolphins utilizing Samadai daytime for resting and socializing. From the 255 identified dolphins, 33 individuals (12.9%) were re-sighted for 4-8 times and 131 individuals (51.4%) were only observed once. The discovery curve indicated the continuous entrance of new animals to Samadai reef, which increased between May and December.

he distribution of fish larvae near coral reefs can be influenced by physical and biological factors. This paper aims to determine the influence of some ecological features of adult fish on the distribution of their larva stages at offshore and inshore sites. The spawning mode of the adults, their habitats and the depth of water column at which they live were investigated. Fish larval were collected from Hurghada by plankton net of 0.5 mm mesh size from January to December 2005. The Chi square test showed that the distribution of fish larvae in the area was dependent on the spawning mode and neither on the adult habitat nor the depth they live at. The analysis of variance ANOVA indicated that the distribution of larvae of pelagic fishes was significantly different between offshore and inshore sites. The study has provided further information on the distributional patterns of the larvae of coral reef fishes that help to understand the interrelationships among fish species during their larval stages.

The natural feeding of 609 Octopus aegina was studied in relation to the environmental seasonal variations in three populations in the Suez Canal, the Gulf of Suez and the Mediterranean Sea. Samples were collected seasonally from March 2009 till May 2010. Analysis of the stomach contents revealed that O. aegina attained the highest percentages of empty stomachs during spring for the three populations. The (1/2) full stomachs was dominant in the collected samples (32.97 %). The study revealed that 34.43 %, 32.83 % and 32.10 % of the examined stomachs were empty in the samples of Suez Canal, Gulf of Suez and Mediterranean, respectively. There was no definite seasonal food preference, and crustaceans were the most preferable food item followed by fishes. The biochemical composition of O. aegina revealed that females are higher than males in total protein content (72.41 % and 69.29 % for immature and mature females respectively) and total lipid content (38.4 g/100 g dry weight and 33.2 g/100 g dry weight for immature and mature females respectively). Amino acid analysis showed that O. aegina contains higher percentage of non essential amino acids (NEAA) than essential amino acids (EAA). Leucine, Lysine and Arginine had the highest percentage of EEA, while Asparagine, Glutamate and Glycine had the highest percentage of NEAA. EAA in males increased from 36.64% to 37.93 % in immature and mature respectively, while in females it increased from 36.93 % to 41.5 % in immature and mature respectively. Fatty acid analysis showed that males O. aegina contain higher percentage content of fatty acid components (SFA and UFA) than females. The results also revealed that SFA tended to decrease by maturation in males and females. Palmitic (16:0) and Stearic (18:0) were the most abundant SFA. Mature males had the highest percentage content of PUFA.