Article impact statement: Environmental DNA provides habitat-characteristic molecular signatures and can be used efficiently to map marine biodiversity at large spatial scales.

Ocean circulation, geological history, geographic distance, and seascape heterogeneity play an important role in phylogeography of coral‐dependent fishes. Here, we investigate potential genetic population structure within the yellowbar angelfish (Pomacanthus maculosus) across the Northwestern Indian Ocean (NIO). We then discuss our results with respect to the above abiotic features in order to understand the contemporary distribution of genetic diversity of the species. To do so, restriction site‐associated DNA sequencing (RAD‐seq) was utilized to carry out population genetic analyses on P. maculosus sampled throughout the species’ distributional range. First, genetic data were correlated to geographic and environmental distances, and tested for isolation‐by‐distance and isolation‐by‐environment, respectively, by applying the Mantel test. Secondly, we used distance‐based and model‐based methods for clustering genetic data. Our results suggest the presence of two putative barriers to dispersal; one off the southern coast of the Arabian Peninsula and the other off northern Somalia, which together create three genetic subdivisions of P. maculosus within the NIO. Around the Arabian Peninsula, one genetic cluster was associated with the Red Sea and the adjacent Gulf of Aden in the west, and another cluster was associated with the Arabian Gulf and the Sea of Oman in the east. Individuals sampled in Kenya represented a third genetic cluster. The geographic locations of genetic discontinuities observed between genetic subdivisions coincide with the presence of substantial upwelling systems, as well as habitat discontinuity. Our findings shed light on the origin and maintenance of genetic patterns in a common coral reef fish inhabiting the NIO, and reinforce the hypothesis that the evolution of marine fish species in this region has likely been shaped by multiple vicariance events.

No abstract

Countries that border the Persian or Arabian Gulf (hereafter "Gulf") are adopting ambitious global commitments to protect their marine environments (1). The United Arab Emirates (UAE) has committed to protecting 30% of their lands and waters, with other Gulf states expected to soon join. Gulf countries will not meaningfully meet these and other global commitments (e.g., post-2020 biodiversity framework) without rebuilding trust, exchanging knowledge, and jump-starting conservation coordination across their maritime boundaries. Gulf scientists have an overlooked role in this work. The Gulf's political boundaries are crowded among Bahrain, Iran, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, and the UAE, making the regional networking of marine protected areas Letter for Science (Policy Forum) -submitted May 24, 2022 3 (MPAs) critical to system-wide conservation success (2). During the summer, the Gulf is the world's hottest marine system, with many organisms living near their physiological limits (3,4).

No abstract

Low‐density polyethylene (LDPE) and polystyrene (PS) films with hydrophilic surface were prepared by photochemical grafting of sulfobetaine‐based copolymer containing photolabile moiety, and long‐term stability of the hydrophilic nature of the surfaces in seawater was proved. The sulfobetaine‐based copolymer was prepared by copolymerization of N,N‐dimethyl‐N‐(3‐(methacryloylamino)propyl)‐N‐(3‐sulfopropyl) ammonium betaine with 2 or 5 mol% of N‐methacryloyl‐4‐azidoaniline, and the resulted polymers were grafted onto the plasma pretreated LDPE and PS films. The contact angle measurements were used to prove the modification as well as to follow the changes in the hydrophilicity during storage at room temperature under air atmosphere as well as in seawater at 32°C. The stability of the polymer layer was confirmed also by FTIR and AFM. Polysulfobetaine‐modified LDPE and PS surfaces exhibited significantly higher long‐term hydrophilicity compared with only plasma treated LDPE and PS surfaces.

No abstract

Coral reefs are one of the most biologically diverse and complex marine ecosystems that are being degraded at rapid rates. This consistent steadily trend is especially critical in coastal areas that have experienced an impressive coastal development, as has been occurring in the Arabian Gulf. This Gulf harbours the coral reefs subjected to one of the most extreme environmental conditions worldwide, i.e. high salinities (often >45 psu) and high sea temperatures (> 36° during summer season), together with extensive coastal development that have altered significantly the coastal regions of Bahrain, Qatar and UAE. In these countries most of coastal coral reefs have disappeared throughout the last decades because of habitat loss and alteration; however, offshore coral reefs have been away from these extensive disturbances and they may be considered as regional hotspots of corals. Even, the massive presence of submerged structures from offshore oil and gas platforms needs to be taken into account, since preliminary exploratory field surveys have shown a rich fouling community, dominated by a high variety of sessile groups. Thus, the conservation of coral reefs and associated macroinvertebrates and fish could be enhanced by studying the unexplored artificial reefs that grow attached to submerged structures of offshore oil platforms. This objective is currently being pursued in the framework of the project “Connectivity, diversity and genetic flow between offshore natural coral reefs and oil platforms - NPRP No.: 7-1129-1-201”. We herein analyzed video footages from oil platforms located at the Al Shaheen Oil Field, ca. 90 km offshore NE Qatar. The visual assessment was done by Maersk Oil Qatar in 2014, via a remotely operated vehicle (ROV). The video recordings were done during routine inspections conducted in 20 oil platforms, located at 8 locations. A total of 2000 video files were analyzed to study the relative abundance of Al Shaheen Oil Field's macroinvertebrates, using the CATAMI (Collaborative and Annotation Tools for Analysis of Marine Imagery and Video) classification scheme. This guide has been designed to promote consistency and standards for classifying marine biota and substrata captured in underwater imagery from a broad range of depths (shallow-abyssal) and habitats (temperate reefs, corals, etc.). A total of 17 morphology-based functional groups were identified (Encrusting; Porifera, Octocorallia, Hydrozoa and Bryozoa; Turf: Hydrozoa and Bryozoa; Fleshy arborescent: Antipatharia, and Octocorallia; Hard Coral: Scleractinia; Foliaceous: Hydrozoa and Bryozoa; Barnacle: Cirripedia; Bivalve: Mollusca; Massive simple: Porifera; None Flesh Bushy: Antipatharia, and Octocorallia; Fan Simple: Antipatharia, and Octocorallia; Fan Complex: Antipatharia, and Octocorallia; Whip: Antipatharia, and Octocorallia; Bryozoa: Bryozoa; Anemone: Actiniaria; Unstalked crinoid: Crinoidea; Regular urchins: Echinoidea). The MNCR's (Marine Nature Conservation Review) SACFOR (Superabundant, Abundant, Common, Frequent, Occasional and Rare) semi-quantitative abundance scale was used to study the relative macroinvertebrate abundance. The submerged structures of the oil platforms were studied from 0-60 m depth, divided into 8 depth layers (0-10, 10-20, 20-30, 30-40, 40-45, 45-50, 50-55 and 55-60 m), with time intervals of 30 seconds per layer. PERMANOVA (Permutational Multivariate Analysis of Variance) was used to calculate the similarities among samples using the resemblance of Bray-Curtis similarity. Age and depth were the main factors structuring the sessile macroinvertebrate community in the studied platforms. In contrast, no differences in community structure were found among the platform locations, probably due to the high level of connectivity within the Al Shaheen Oil Field. A total of 8 functional groups contributed >10% to the average dissimilarity of the community (hard coral, fleshy arborescent, foliaceous, encrusting, turf, barnacles, bivalve and massive simple). A clear vertical gradient is apparent for the coverage of epibenthic macroinvertebrates, with diversity and biomass increasing with depth. Encrusting sponges and bryozoans are dominant at shallow depths. Other types of macroinvertebrates become dominant as depth increases, such as foliaceous bryozoans and hydrozans, massive sponges, bivalves, anemones, crinoids and octocorals. Fleshy arborescent octocorals (Dendronephthya sp.) and azooxanthellate scleractinian corals were frequently found on the Al Shaheen oil platforms, at depths greater than 30m. The abundance of both groups tends to increase with depth and the hard corals also tend to be more abundant on older platforms. This study clearly showed that azooxanthellate scleractinian, reef building corals are recruiting and growing on the platforms the Al Shaheen Oil Field, in some cases at high densities. Given that no specimens could be obtained, precise taxonomic identification was not possible, but their morphology suggests they belong to the Caryophylliidae family. This finding is highly significant, given that this type of corals has not previously been reported in Qatari waters. Furthermore, it clearly illustrates the potential of this type of offshore infrastructure to support the establishment of functional reef ecosystems in areas where they are degraded or were previously absent, thus contributing to offset the current net loss of this important type of natural marine habitat.