Ibrahim Bugla’s research while affiliated with Environment Agency - Abu Dhabi and other places

Knowledge of the habitat use of wildlife in highly impacted areas is essential to identify areas of biological importance and to implement appropriate conservation measures. The Arabian Gulf represents one of the most extreme marine environments and is considered one of the regions in the world with the greatest anthropogenic impact. Information on the habitat use and abundance of marine top predator species is, however, lacking, despite being a prerequisite for effective planning of conservation measures. Here, we provide novel information for the Indo-Pacific bottlenose dolphin (Tursiops aduncus) in the Arabian Gulf (Abu Dhabi, United Arab Emirates). Data from 80 daily surveys conducted between June 2014 and November 2019 were used both to assess correlates of bottlenose dolphin habitat use and relative density and to calculate mark-recapture abundance estimates. This study confirms the strong adaptability and tolerance of this top marine predator to extreme environmental conditions within a highly heterogeneous and impacted marine habitat. The observed preferences for areas with less human pressure were likely a result of the interactions of environmental factors with prey availability and human disturbance. This study also provides the first abundance estimates for a bottlenose dolphin population in the Arabian Gulf. Our findings support the call for increased marine-protected areas and the creation of transboundary conservation areas in the region. Regional connectivity should be of value to marine predators whose wide distribution and vulnerability to human activities means that alteration of their habitats can result in population declines and eventual local or regional extinctions.

Knowledge of the habitat use of wildlife in highly impacted areas is essential to identify areas of biological importance and to implement appropriate conservation measures. The Arabian Gulf represents one of the most extreme marine environments and is considered one of the regions in the world with the greatest anthropogenic impact. Information on the habitat use and abundance of marine top predator species is however lacking, despite being a prerequisite for effective planning of conservation measures. Here, we provide novel information for the Indo-Pacific bottlenose dolphin ( Tursiops aduncus ) in the Arabian Gulf (Abu Dhabi, United Arab Emirates). Data from 80 daily surveys conducted between June 2014 and November 2019 were used both to assess correlates of bottlenose dolphin habitat use and relative density and to calculate mark-recapture abundance estimates. This study confirms the strong adaptability and tolerance of this top marine predator to extreme environmental conditions within a highly heterogeneous and impacted marine habitat. The observed preferences for areas with less human pressure were likely a result of the interactions of environmental factors with prey availability and human disturbance. This study also provides the first abundance estimates for a bottlenose dolphin population in the Arabian Gulf. Our findings support the call for increased marine protected areas and the creation of transboundary conservation areas in the region. Regional connectivity should be of value to marine predators whose wide distribution and vulnerability to human activities means that alteration of their habitats can result in population declines and eventual local or regional extinctions.

Adult sea turtles migrate between foraging areas and nesting sites that may be 100 s–1000 s of km away. Little is known of the connectivity between these sites in the Arabian region for green sea turtles. We document linkages between two foraging areas in the United Arab Emirates (UAE) with key nesting sites and provide insights on effectiveness of marine protected areas for green sea turtles. Tracking 45 adult green sea turtles Chelonia mydas from foraging areas in the UAE, we show that the primary nesting destination for turtles foraging in Bu Tinah in the UAE is Ras al Hadd in Oman. The turtles use the waters of the UAE, Iran and Oman during breeding migrations and generally stay ~ 20 km off the coast, in waters 10–20 m deep except when crossing the Sea of Oman. Turtles display substantial fidelity to the original foraging sites, often traversing other known foraging sites when returning from the breeding migration. A small proportion of turtles also utilise more than one foraging site. Our data indicate that the Marawah Marine Biosphere Reserve in Abu Dhabi is broadly coincident with the foraging areas of turtles offering substantial protection from fishery activities and that the marine protected area in Ras Al Khaimah would be more effective in protecting green sea turtles if it extended offshore and along the coast. These data may contribute to targeted and effective national and international management and conservation initiatives in the Arabian region.

Adult sea turtles undertake periodic long-distance migrations between foraging and nesting areas during breeding migrations, and an understanding the connectivity between these two important habitats can contribute to efficient conservation planning. We present the first round-trip migrations of three green sea turtles in the Arabian region, from a foraging area to a nesting site and back, along with an interpretation of reproductive behaviour which would not have been possible from open-ended tracks. We studied habitat connectivity between seagrass foraging areas in the UAE and nesting beaches, and used laparoscopy as a diagnostic tool to determine gender and reproductive state to enhance the value of satellite tracking data. We identify habitat connectivity between a foraging area at Bu Tinah in the UAE and a nesting site at Ras al Hadd in Oman, document migratory behaviour in the Arabian region, and demonstrate the enhanced value of combining laparoscopy when satellite tracking sea turtles from foraging areas. The results of our work can help develop bilateral or multi-lateral conservation strategies, contribute to the identification of Important Turtle Areas (ITAs), and support national and regional population assessments. In addition, our findings will complement risk assessments for sea turtles in the face of urban and industrial development, climate change, fishery pressure, and shipping activities. This work successfully linked foraging areas and nesting sites, and our approach can be used to provide value-added benefits to future tracking of sea turtles from foraging areas.

Like coral reefs around the world, the reefs of the United Arab Emirates (UAE) are facing global climate change and associated threats. The coasts and islands that flank Abu Dhabi host an important number of corals that should be the focus of conservation actions. Well-designed conservation and management plans require efficient monitoring systems that include understanding coral reef patterns. To understand some of these patterns; coral cover data, satellite-derived and in-situ water quality parameters from nine key reef environments in the UAE from 2011 to 2014 to model coral patterns were used. The objectives were to model coral patterns and realistically predict coral damage intensity with changing environmental variables. Coral damage cover models were defined and estimated for the coral damage cover. Effects of environmental factors were estimated, and predictions of coral damage intensity were presented with changing factors. Main findings, based on the studied data, showed that nutrient enrichment, a proxy for anthropogenic pressure, and salinity are the most influential factors to induce coral damage in UAE waters. Furthermore, results demonstrated that the probability of severe damage increases with decreasing water oxygenation and with increasing temperature, light, salinity, acidity and nutrient levels. The defined and estimated predictions accounted for corals’ behavioural aspects, across individual reefs and over time. This approach is more appropriate than estimation predictions that just account for historic trends. Nevertheless, there are, probably, many components within the model framework that can be expanded and/or improved as more information become available. An extended dataset will enable a means to independently validate the defined models and test other modelling approaches. Continually increasing the in-situ and remote sensing data sizes, spatially and temporally, defines a long-term priority.

The Emirate of Abu Dhabi is strategically located within the Arabian Gulf in a combination of geographical, oceanographic and ecological conditions which enable the presence of a rich cetacean fauna. Although the preservation of suitable habitats is necessary, the persistence of cetacean species in Abu-Dhabi waters cannot occur without a better understanding of their distribution, demography and use of habitat. Here we report the distribution patterns and group dynamic of cetacean species as integral components of the information needed to manage human impacts on marine mammals in Abu Dhabi waters. Overall, 13 days were spent at sea in April 2017, totaling 107 hours and 1 145 km of boat-based observations. During this time there were 57 encounters with cetaceans (35 with Indo-pacific bottlenose dolphins, 14 with Indian Ocean humpback dolphins, and 8 with finless porpoises). During these encounters 268 Indo-pacific bottlenose dolphins, 92 Indian Ocean humpback dolphins, and 37 finless porpoises were observed. These surveys confirm Abu Dhabi waters as an important foraging habitat for all these cetacean species. Indeed, behavioural data confirm Abu Dhabi waters as a breeding/nursery zone for Indian Ocean humpback dolphins and Indo-pacific bottlenose dolphins. Although the Abu-Dhabi humpback dolphin population is considered one of the largest in the genus Sousa in the world, based on previous studies, the observed decline in presence of humpback dolphins could be cause of concern. A number of interacting factors may have played a role in this decline, ranging from natural fluctuations to the potential impact of human activities such as oil and gas exploration (including seismic surveying) in the Central region during the surveys period. Therefore, further surveys are needed to confirm if this decline is result of a short-term seasonal variation in presence or on the contrary, is due to a real decline in the occurrence of this endangered species.

Humpback dolphins threats in the Arabian Gulf

The Arabian Gulf is one of the most heavily impacted water bodies raising serious concerns about the conservation status of many marine species. A limited coastal range and near-shore distribution make Indian Ocean humpback dolphins particularly vulnerable to mortality and traumatic injuries from heavy maritime traffic and gill-netting practices. Prior to the present study, no research had focused on the ecology of this species in the Arabian Gulf, despite the potential for human impacts. The mark–recapture method of photo-identification, undertaken during 55 boat-based surveys conducted between 2014 and 2015, was used to assess the occurrence, abundance and use of habitat of this endangered species along the coast of the Emirate of Abu Dhabi (UAE). In all, 368 h and 6703 km of observation were carried out over a period of 5 months, and 54 encounters were made with humpback dolphins. The group size ranged from 1 to 24 individuals and group composition showed that 79% of the observed dolphins were adults. Abundance estimates were calculated and fitted with open population models. A review of all available data indicates that the studied population is the largest reported in the world with 701 (95% CI = 473–845) individuals. While their occurrence within Abu Dhabi near-shore waters is frequent, the survey area appears to be only a part of a much larger home range for this humpback dolphin population. The observation of multiple threats derived from anthropogenic activities increases our concerns regarding the conservation of this important dolphin population.

The waters of the southern Arabian Gulf are the most extreme marine environ-ment on the planet with temperatures ranging from 16 oC during the winter to over 36oC in the summer. We initiated a dolphin monitoring programme in the coastal waters of the Emirate of Abu Dhabi in the United Arab Emirates in 2014 in order to define the distribution, abundance, habitat use, residence patterns and threats to dolphins in these waters. There were 39 sightings made; 20 with Indian Ocean humpback dolphins (Sousa plumbea), 18 with Indo-Pacific bottlenose dolphins (Tursiops aduncus) and 1 with the Indo-Pacific finless porpoise (Neophocaena phocaenoides). The pres-ence of bottlenose dolphins showed a peak during summer and the presence of humpback dolphins showed a peak during winter. Photo identification results suggest that the Indian Ocean humpback dolphin is resident in Abu Dhabi waters whereas the Indo-Pacific bottlenose dolphin is transient. Because of their small population size and limited coastal range, the Indian Ocean humpback dolphin could be particularly vulnerable to local extinction. Key anthropogenic threats are injury and mortality associated with propeller strikes and the potential for drowning due to entanglement in coastal net fisheries.