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The increase in maritime traffic means that ports have to continuously improve their efficiency. This involves reducing the inactivity caused by adverse conditions that affect its operation and maintenance which includes the sedimentation rate, the shallow depth, water current regimes and tidal cycle. This study examines the hypothesis that these factors could affect Taba Heights international marina. The results showed that the harbor offered very good protection against sediment deposition (rate of sediment deposition ranging from 0.2 to 1.9 mg•cm

Background: Sea cucumber populations in the Egyptian Red Sea have been exploited by uncontrolled fishery with no management takes place. The sea cucumber populations were surveyed at Abu Ghosoun area, Red Sea, during three period intervals in 2000, 2006, and 2016. Results: In 2000 and 2006, the total number of recorded species was 13 species, which decreased to only 7 species in 2016. The population density of sea cucumber were greatly affected by overfishing and showed a uniform pattern of very low density in 2006 and 2016 after the high density recorded in 2000. Holothuria atra recorded the highest density that reached 128.1 ind./100 m 2 in 2000 and decreased to 120.4 ind./100 m 2 in 2006 and 87.4 ind./100 m 2 in 2016. The dramatic decrease in densities was observed in other recorded species as in Thelenota ananas which decreased from 48.1 ind./100 m 2 in 2000 to only 5.6 ind./100 m 2 in 2006 and completely disappeared during 2016. The total abundance of all sea cucumber species recorded during 2000 was 13,880 individuals, which decreased to 7700 individuals in 2006, then to only 2420 individuals in 2016. The remaining individuals in 2016 comprise only 17.4% of the original population recorded in 2000, which means that 82.6% of the sea cucumber populations were lost during the 16 years. The study showed a difference in relative abundance between different species and years. In 2000, the relative abundance ranged between 3.03% for Actinopyga miliaris and 18.44 for Holothuria atra. In 2006, the relative abundance ranged between 2.08% for Stichopus horrens and 31.17% for Holothuria atra. While in 2016, the relative abundance ranged between 0% for several species and 71.9% for Holothuria atra. The total biomass recorded showed high decrease from 10,373.8 kg in 2000 to 5461 kg during 2006 and 1379.6 kg in 2016. Conclusion: The study revealed that sea cucumber species diversity and density were much reduced from 2000 to 2016. It also revealed a difference in dispersion among the different years of investigation, indicating the high influence of overfishing on the sea cucumber populations.

Over the last decade, holothuroid sea cucumbers in the Gulf of Aqaba of the Red Sea have been the target of continuous fishing. This has severely depleted sea cucumber stocks, especially the high-value species such as Holothuria fuscogilva. The present work demonstrates that restocking populations of H. fuscogilva that are at critically and chronically low levels by transplanting wild-captured juveniles can be effective. Juveniles were translocated from a robust population at Pharoan Island and released into two sites (Wadi Quny and Hidden Bay). Population density, growth rate and mortality at the original and two release sites were monitored for 2 yrs. The Pharoan population density was highest, with H. fuscogilva showing a strong preference for sandy habitat (21.3 -18.4 ind./100m 2 ), over seagrasses (3.6 -2.5 ind./100m 2 ) and corals (0.9 -1.7 ind./100m 2 ). The restocked population at Wadi Quny increased from 2.6 to 9.8 ind./100m 2 from 2013-2015. In contrast, density at Hidden Bay decreased from 2.8 to only 0.1 ind./100m 2 in the first year. Sea cucumbers in the restocked population at Wadi Quny had higher growth rates (0.65 -1.29 cm/month) compared to the original population at Pharoan Island (0.21 -0.45 cm/month), while Hidden Bay showed a negative growth rate. Mortality was low at Pharoan Island (1% -2%) and Wadi Quny (0.5% -0.75%), but high at Hidden Bay (49% -100% in the first year). There was a negative relationship between mortality and size (P = 0.003). The restocking of H. fuscogilva populations using wild-captured juveniles was very successful at Wadi Quny but a failure at Hidden Bay.All applicable international, national and/or institutional guidelines for the care and use of animals were followed by the authors.

Reproduction global warming temperature Gulf of Suez The reproduction patterns of E. mathaei's population at the Gulf of Suez were investigated during two periods, the first was 1992-1993 and the second was 2015-2016. The effects of elevating temperature during these periods on reproduction periodicities were studied. The surface water temperature showed an increase during the period 2015-2016 by 1.36 o C at summer and 1.24 o C at winter from that recorded during 1992-1993. In 1992-1993, individuals of E. mathaei had one definite lengthy spawning season, which were expressed by main spawning period from June to August with maximum gonadal activity in July. On contrary, there was an obvious shift at the spawning season during 2015-2016; individuals of E. mathaei exhibit more than one breeding season. However, they are resting