Search

Mobile species often aggregate at predictable places and times to ensure that individuals find mates and breed in suitable habitats. Sea turtles demonstrate this life history trait, which can make these species highly susceptible to population declines if nesting habitats are lost or degraded. Conservation management thus requires knowledge of where and when turtles nest and changes in abundance in these habitats through time. Here, we compiled new and published data and used a novel analysis to describe seasonality, annual abundance and spatial distribution of nesting green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) turtles in data-deficient populations that inhabit the Red Sea. Major new rookeries were identified for green turtles at Jazirat 1 Mashabah (113 and 179 nesting females in 2018 and 2019) and for hawksbill turtles at Jazirat Al Waqqadi (79 nesting females in 2018), both of which are located on nearshore islands of the Kingdom of Saudi Arabia in an area subject to industrial, residential and ecotourism developments. An upward trend in annual abundance of nesting sea turtles was estimated at some sites including Ras Al Baridi (Saudi Arabia), a major rookery of green turtles in the Red Sea, where the annual numbers increased from 14–110 individuals in 1982–1995 to 178 and 330 individuals in 2018 and 2019. This integrative work provides the most up-to-date, comprehensive information on nesting sea turtles in the Red Sea and documents a critical baseline for sea turtle conservation and future management effort.

Fish contamination has been extensively investigated along the Saudi coasts, but studies pertaining to bacterial pathogens are scarce. We conducted qualitative assessment and molecular identification of culture-dependent bacteria in 13 fish species from three coastal sites and a local fish market in Jeddah, Saudi Arabia. Bacterial counts of gills, skin, gut and muscle were examined on agar plates of Macconkey’s (Mac), Eosin Methylene Blue (EMB) and Thiosulfate Citrate Bile Salts (TCBS) culture media. Bacterial counts significantly differed between species, sources and feeding habits of examined fishes. Mugil cephalus exhibited higher counts on TCBS (all body parts), Mac (gills, muscle and gut) and EMB (gills and muscle). Fishes from Area I had higher bacterial loads, coinciding with those in seawater and sediment from the same site, indicating direct association between habitat conditions and the levels of bacterial contamination. By feeding habit, detritivorous fish harbored higher counts than herbivorous and carnivorous species. Bacterial counts of skin were higher in fish from market than field sites, and positively correlated with other body parts indicating the relation of surface bacterial load on the overall quality of fish. Rahnella aquatilis (Enterobacteriaceae) and Photobacterium damselae (Vibrionaceae) were among the dominant species from fish muscle based on 16S rRNA sequencing. These species are known human pathogens capable of causing foodborne illness with severe antibiotic resistance. Opportunistic pathogens, e.g. Hafnia sp. (Enterobacteriaceae) and Pseudomonas stutzeri (Pseudomonadaceae) also occurred in fish muscle. The inclusion of bacterial contamination in future monitoring efforts is thus crucial. Keywords: Marine environment, Fish, Bacterial contamination, Population count, Molecular identification, Sanger sequencing

All 209 congeners of polychlorinated biphenyls (PCBs) in edible fish tissue from the central Red Sea coast (Jeddah region) of Saudi Arabia were analyzed by isotope dilution high-resolution gas chromatography–mass spectrometry. The upper-bound total PCB (ΣPCB) levels in nine commonly consumed fish species from three areas were 0.2–82.5 ng/g wet weight (17–8450 ng/g lipid weight), which were at the lower end of reported global range and far below international tolerance limits (500–3000 ng/g ww). Dioxin-like congeners contributed up to 12.8% (mean 6.5%) to ΣPCB in tissue samples, with the total PCB toxic equivalencies (TEQs) at a tolerable range (0.05–2.6 pg TEQ/g ww or 2–238 pg TEQ/g lw) for all species. PCB profiles were dominated by moderately chlorinated homologs, mainly hexachlorobiphenyls, but less chlorinated congeners were also consistently elevated, notably in Siganus rivulatus (Area III) and Mugil cephalus (Area I). It remains to be ascertained if the latter were breakdown products or due to fresh inputs. The top congeners based on dominance by both occurrence and abundance were identified as potential markers of ΣPCB in fish tissue, which can be used for future selective biomonitoring in case of reasonable constraints on full congener approach.

We thank the Center for Environment and Water (CEW) at the Research Institute of King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia, for providing research facilities and the Marine Studies Section team of CEW for performing the fieldwork and laboratory analyses. We express our sincere thanks to the General Authority of Meteorology and Environmental Protection, Saudi Arabia and Saudi Company for Environmental Works Ltd. for their constant support. We also thank M/S Al- Gosaibi for providing services of their Oceanographic Vessel.

A new cold brine seep system with microbial mats and metazoan assemblages was discovered by a remotely operated vehicle (ROV) on the Saudi continental margin of central Red Sea. Now named as Thuwal Seeps, it has a shallow brine pool between 840 and 850 m water depths that is formed by focused brine expulsions from two sites (Seep I: 22°17.3′N, 38°53.8′E; Seep II: 22°16.9′N, 38°53.9′E). The seep is located at the base of a steep wall rock closer to the shore (20 km) than to the axial trough (120 km). The brine pool does not exhibit a significant thermal anomaly (

The 1991 Gulf oil spill heavily impacted the coastal areas of the Saudi waters of the Arabian Gulf and recent studies have indicated that even 15 years after the incident, macrobenthos had not completely recovered in the sheltered bays in the affected region such as, Manifa Bay. This study investigates the community conditions of macrobenthos in the open waters in one of the impacted areas, Al-Khafji waters, about 14 years after the spill. Diversity measures and community structure analyses indicate a healthy status of polychaete communities. The BOPA index reveals that oil sensitive amphipods were recolonized in the study area. This confirms that the benthic communities of the oil spill impacted area had taken only

Shallow water bays located in the western Arabian Gulf experience harsh environmental conditions. Some of these bays, including Manifa-Tanajib Bay System (MTBS), were also exposed to the 1991 oil pollution event. This study investigates the status of the macrobenthos in MTBS during 2006. This bay system is characterized by very shallow inner bays with elevated salinity and temperature compared to the rest of the bay area. As a result mainly of the hyper salinity, the inner bay communities are distinct from the outer bay communities. Overall, fairly high species richness with several rare species was observed. High Shannon-Wiener diversity values and ABC plots indicated the healthy status of the polychaete communities, while BOPA index indicated slightly polluted status in 20% of the stations. The oil sensitive amphipods were not completely re-colonized in 20% of the stations, even after 15 years of recovery from the 1991 oil spill.