To assess the anthropogenic impact on Egyptian coast of Gulf Aqaba, particularly tourism and fishing influences. Eighteen sites were surveyed from November 2019 to February 2020. At each site, coral cover was determined using Point Intercept Transect (PIT) method, at depths 3 8 m. Also, abundances invertebrate species by belt transect method same for site. Mean percentages corals (hard soft) Da...

We report here, the effects of extended competency on larval survival, metamorphosis, and postlarval juvenile growth of four closely related species of tropical sea urchins, Echinometra sp. A (Ea), E. mathaei (Em), Echinometra sp. C (Ec), and E. oblonga (Eo). Planktotrophic larvae of all four species fed on cultured phytoplankton (Chaetoceros gracilis) attained metamorphic competence within 22-...

Data concerning the effects of high CO2 concentrations on marine organisms are essential for both predicting future impacts of the increasing atmospheric CO2 concentration and assessing the effects of deep-sea CO2 sequestration. Here we review our recent studies evaluating the effects of elevated CO2 concentrations in seawater on the mortality and egg production of the marine planktonic copepod...

Morphological, mitochondrial DNA, and single-copy nuclear DNA differences show that the tropical sea urchin Echinometra mathaei is composed of at least four independent gene pools. Evolutionary distance between species measured with restriction-site changes (for mitochondrial DNA) and thermal renaturation (for single-copy nuclear DNA) is 1%-3% nucleotide divergence. Thus these are the most clos...