Coral cover and community structure in the Arabian Gulf have changed considerably in recent decades. Recurrent bleaching events have dramatically reduced the abundance of previously dominant
Acropora
...corals and have given space to other more thermally resistant coral taxa. The loss of
Acropora
spp. has reduced reef structural complexity and associated biodiversity. Sir Bu Nair Island (SBN) is a nature reserve in the United Arab Emirates that sustains some of the last dense and extensive
Acropora
stands in the southern Gulf. This study investigated coral recruitment at a southern coral reef on SBN and examined larval dispersal and reef connectivity between SBN and other local and regional reefs through an agent-based model coupled with a 3D hydrodynamic model. Recruitment was surveyed with settlement tiles deployed from April to September 2019. Contrary to other reefs in the Gulf, we found that
Acropora
is indeed the major coral recruiter settling at SBN reefs, followed by
Porites
. The models indicate that SBN reefs are mostly self-seeding but also connected to other reefs in the Gulf. SBN can supply coral larvae to the neighbouring islands Siri and Abu Musa, and nearby reefs along with the north-eastern Emirates, Iranian coast and Strait of Hormuz. Findings highlight the importance of SBN to protect remnant populations of the locally almost extinct
Acropora
in a region where natural coral recovery is increasingly sparse.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Two individuals of
Epinephelus coeruleopunctatus
(Bloch, 1790), Whitespotted Grouper, were recorded in an offshore marine protected area of the United Arab Emirates on the Arabian Gulf coast at ...depths of 5 m and 10 m. These are the first records of the species in the southern Arabian Gulf, and they add this species to the few groupers that inhabit one of the most extreme environmental waters of the world.
The ecological state of the Persian or Arabian Gulf (hereafter ‘Gulf') is in sharp decline. Calls for comprehensive ecosystem-based management approaches and transboundary conservation have gone ...largely unanswered, despite mounting marine threats made worse by climate change. The region's long-standing political tensions add additional complexity, especially now as some Gulf countries will soon adopt ambitious goals to protect their marine environments as part of new global environmental commitments. The recent interest in global commitments comes at a time when diplomatic relations among all Gulf countries are improving. There is a window of opportunity for Gulf countries to meet global marine biodiversity conservation commitments, but only if scientists engage in peer-to-peer diplomacy to build trust, share knowledge and strategize marine conservation options across boundaries. The Gulf region needs more ocean diplomacy and coordination; just as critically, it needs actors at its science-policy interface to find better ways of adapting cooperative models to fit its unique marine environment, political context and culture. We propose a practical agenda for scientist-led diplomacy in the short term and lines of research from which to draw (e.g. co-production, knowledge exchange) to better design future science diplomacy practices and processes suited to the Gulf's setting.
The United Arab of Emirates (UAE) hosts valuable coastal and marine biodiversity, and oysters are one of the habitants of its marine ecosystem. Oysters play an essential role in the nearshore coasts ...where they work as an active filter. They filter nutrients, phytoplankton, sediments, heavy metals, and toxins out of the water, which improves the water quality. This is the first study that characterizes oyster bed habitats in the UAE by analyzing water quality parameters, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs)and heavy metals in water, sediments and oyster samples collected from five locations along the coasts of Sharjah, Ajman, and Umm al Quwain. Oyster bed areas supported a diverse assemblage of benthic life including oysters, scallops, pen shells, hard corals, and macroalgae. Mobile species in these habitats included groupers, emperors, snappers, sea snakes, among others. The phytoplankton assemblages were dominated by diatoms, dinoflagellates, and small cryptophytes. Harmful diatom Pseudonitzschia was found in all locations. No detectable concentrations of PAHs and OCPs were reported in this study, and water quality parameters were within the acceptable levels for the region. On the other hand, water quality index was reported marginal, mostly due to the presence of higher than acceptable concentrations of chromium and mercury in all sites studied. Bioconcentration factors concluded that oysters were able to bioconcentrate metals such as arsenic, cadmium, chromium, and zinc, when compared to water. No detectable concentrations of lead and mercury were reported in oysters, suggesting higher depuration rates for those metals.
•Oyster Bed habitats in the UAE have historical, societal, and economical value.•PAHs and OCPs were below detection, while heavy metals were detected in sediments, water, and oysters.•Zinc, arsenic, and cadmium had the highest concentrations in oysters than in water and sediments.•Diatoms, dinoflagellates, and small cryptophytes were the dominating phytoplankton assemblages.•Oysters, scallops, pen shells, hard corals, and macroalgae were the most common benthos in UAE.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
There is scarce information on the current importance of oyster beds as fishing grounds in the United Arab Emirates (UAE). This study aims to understand the socio-economic value of oyster bed ...fisheries through questionnaire-based surveys with fishers. Of 106 Emirati fishers interviewed, 67 % use oyster beds due to the proximity to shore, better catch quality, and species abundance. Oyster bed fisheries are recreational and commercial, with handline and fish traps the most common used gears. They provide food for local consumption and cash income. All respondents noticed a fish abundance and size decrease throughout the last decade. Fishers suggest establishing marine protected areas and updating fishing regulations to improve fishing stock status. During the Covid-19 pandemic, oyster fisheries increased, highlighting the value of these fishing grounds for food availability. These fisheries support the local economy and heritage, and urgently need management to ensure the protection of these often-overlooked habitats.
•Oyster beds provide food and income for local communities in the UAE.•Fishers were interviewed to assess their importance as fishing grounds.•Fishers indicated reductions in oyster beds' area and fish abundance and size.•Fishing activities in oyster beds habitats increased during the Covid-19 pandemic.•Management actions are needed to preserve oyster bed habitats and fisheries.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Shallow coastal lagoons are vital ecosystems for many aquatic species and understanding their biodiversity is essential. Very little is known about the distribution and abundance of globally ...threatened marine megafauna in coastal lagoons of the Arabian Gulf. This study combined underwater and aerial surveys to investigate the distributions and relative abundance of marine megafauna in a large lagoon. We identified 13 species of megafauna including sea turtles, sharks, and rays. Eleven of these are globally threatened according to the IUCN Red List of Threatened Species. The Critically Endangered Halavi guitarfish (Glaucostegus halavi), and the Endangered green turtle (Chelonia mydas) were the most frequently occurring species. Results demonstrate the value of combining aerial and underwater video surveys to obtain spatially comprehensive data on marine megafauna in shallow coastal lagoons. This new information emphasises the importance of Umm Al Quwain lagoon for biodiversity conservation to protect threatened marine species and their habitats.
•Coastal lagoons of the Arabian Gulf host globally threatened marine megafauna.•We combined aerial and underwater surveys to investigate megafauna.•We identified 13 species of megafauna, including sea turtles, sharks, and rays.•Threatened Halavi guitarfish and green turtles were the most abundant.•Key information to support conservation actions in UAE coastal lagoons
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Coral reefs across the southern Arabian Gulf have declined in the past two decades, with extensive loss of formerly Acropora table corals, which are now functionally extinct in nearshore reefs. This ...study documents the coral community at Sir Bu Nair (SBN), an offshore island buffered by less extreme environmental conditions, which contains the last remaining large stands of Acropora in the southern Gulf. We found that Acropora is a major reef-building coral throughout SBN. Mean coral cover was 27% (range: 6%–49%) across all sites and depths, of which more than half was comprised by Acropora. This varied around the island, with the highest densities to the south and southwest in shallow waters. Our study provides essential information for the management and conservation of these highly valuable and vulnerable corals.
•Sir Bu Nair MPA conserves the last Acropora spp. reefs in the southern Arabian Gulf.•We studied coral community changes in depth, location and before and after summer.•Mean coral cover was 27% and corals belonged to 14 genera and 10 families.•We found significant differences in coral assemblages among depths and locations.•This MPA protects a unique coral community with Acropora dominated reefs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Mesophotic coral ecosystems (MCEs) were compared between La Parguera and Ponce, off the south coast of Puerto Rico. In contrast to La Parguera, Ponce has a narrow insular shelf and hosts several ...river outlets, a commercial port, a regional sewage treatment plant with associated deep water outfall, and three deep dredge disposal sites. Off Ponce, MCEs receive higher (16×) rates of sedimentation than off La Parguera, a less impacted site. The most impacted sites were located offshore of Cayo Ratones and are in or down-current and in close proximity to one of the dredge disposal sites. There, MCEs are characterized by a steep, irregular, rocky slope with a cover of fine-grained, dark brown sediment, which increases with depth. At shallower depths, scattered rocky outcroppings are colonized by sponges, black corals and algae. The sediment cover contains two to three times the terrigenous content and a significantly higher percentage of the fine-grained fraction than off La Parguera. Thirteen remotely operated vehicle (ROV) dives east and west of Ponce showed that the deepest depth at which corals were observed increased with distance from Cayo Ratones and did not approach depths observed off La Parguera except at the eastern-most (up-current) site, Caja de Muertos, which was also significantly further offshore. Benthic communities off Caja de Muertos were comparable to those at La Parguera, while off Cayo Ratones, there were no mesophotic corals and sparse development of other benthic macrobiota except sponges. Management authorities should include MCEs when assessing potential impacts from anthropogenic activities and take the necessary steps to reduce local threats.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We investigated the variations of reef fish assemblages on coral reefs that experience different turbidity regimes, by assessing the association between the vertical extinction coefficient for ...photosynthetically active radiation (K
d PAR) and communities of fishes and corals at 21 reef sites in La Parguera, southwest Puerto Rico. Statistical correlations and non-metric multidimensional scaling (NMS) identified turbidity as an important environmental parameter affecting ecological processes on coral reefs, as reflected by changes in the composition and abundance of reef fishes and benthic communities. Lower fish density and species richness was found at turbid sites. Turbidity was also negatively correlated to percent coral cover, which together with rugosity, were additional habitat parameters shaping reef fish assemblages. Bluehead wrasse Thalassoma bifasciatum and yellowtail damselfish Microspathodon chrysurus were species rarely present at turbid sites and abundant at clear ones. The yellowtail hamlet Hypoplectrus chlorurus and sharknose goby Elacatinus evelynae had the opposite distribution along the turbidity gradient. We identified seawater turbidity as an additional predictor of the reef fish community structure in La Parguera, in addition to live coral cover and reef rugosity. Because coral reefs and reef fishes were less complex (lower rugosity, less species richness, less diversity) in more turbid sites, managing for clear water conditions within the coastal area of La Parguera should lead to improved ecosystem resilience and stability, and should become a primary goal of management.
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BFBNIB, NUK, PNG, UL, UM, UPUK
Habitat mapping is essential for the management and conservation of coastal marine habitats. However, accurate and up-to-date habitat maps are rarely available for the marine realm. In this study, we ...mapped the coastal marine habitats of >400 km of coastline in the north-western United Arab Emirates (UAE) using a combination of data sources including remote sensing, extensive ground-truthing points, local expert knowledge and existing information. We delineated 17 habitats, including critical habitats for marine biodiversity such as coral reefs and mangroves, and previously unreported oyster beds and deep seagrasses. This innovative approach was able to produce a coastal marine habitat map with an overall accuracy of 77%. The approach allowed for the production of a spatial tool well-suited for the needs of environmental management and conservation in a previously data-deficient area of the United Arab Emirates.
•Mapping of the coastal and marine habitats of >400 km of coastline.•Innovative approach produced a habitat map with an overall accuracy of 77%.•Integration of multiple data sources including local ecological knowledge.•Oyster beds and seagrass deeper than 5 m were mapped for the first time in the UAE.•Cost-efficient and integrative approach for coastal marine habitat mapping.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
