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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 sawfishes (Pristidae) represent one of the most threatened groups of marine fish around the world. Between October 2015 and June 2016, interviews (n = 82) were conducted to assess the occurrence of sawfish in United Arab Emirates waters and gain insight from fishersí traditional ecological knowledge regarding the status, uses, and cultural significance of sawfish. Almost all respondents (95.1%) had previously seen a sawfish, and 92.6% confirmed that their numbers had declined in the last 20 yr. Most respondents reported encounters in the last 5 to 10 yr, with 18.3% (n = 15) having seen a sawfish in the last 2 yr. Sawfish were not perceived as a culturally significant resource (76.8%) and when caught were primarily used as food, their high-value fins sold to traders, and rostra retained as decorations. The consensus was that while sawfish were previously targeted, they are now caught primarily as bycatch in gill nets. Based on pictures and rostra encountered (n = 19), it appears that the green sawfish Pristis zijsron is more common in United Arab Emirates waters than the narrow sawfish Anoxypristis cuspidata, which is likely to be present off the Ras Al Khaimah coast. While the results of this study provide evidence of a large decline in sawfish, they hint at the possible importance of Abu Dhabi waters as a region where sawfish are still encountered and where research and monitoring, as well as conservation and recovery efforts, should be focused to avoid local extinction and recover their populations.