ASSESSING THE FISHERY AND ECOLOGY OF SHARKS IN THE UNITED ARAB EMIRATES

Large scale shark population declines have been documented worldwide due to overexploitation and the lack of adequate management frameworks to conserve shark stocks. This study aimed at gaining an understanding of the national shark fishery and the trade in shark products from the United Arab Emirates (UAE). Data were collected from June 2010 to October 2012 through interviews with local fishermen, market and landing site surveys, fishery independent surveys, and stomach content analysis. Interviews with local fishermen (n=126) provided information on the fishery characteristics and established that sharks were increasingly targeted due to their high value in the global fin trade industry. Fishermen confirmed that changes in species composition, abundance, and size of sharks have been ongoing for over two decades raising concerns about the sustainability of this fishery. Catch data and genetic analyses established that 30 species of sharks were found in UAE Gulf waters. Landings were dominated by six species, Carcharhinus sorrah, Rhizoprionodon acutus, Carcharhinus limbatus, Loxodon macrorhinus, Carcharhinus dussumieri, and Mustelus mosis, representing over 90% of the total catches. Most of these species were small bodied sharks while large bodied species were mostly below the size of maturation possibly suggesting recruitment overfishing. A fishery independent survey of sharks in nearshore areas also indicated a low level of abundance of sharks in waters off Dubai and Abu Dhabi. Data on the relative abundance, distribution, and various aspects of the biology of all species encountered were collected. Furthermore, a dietary study of stomach contents of R. acutus and L. macrorhinus provided information on their feeding habits suggesting that they have viii different preferences for their prey. Trade data were limited to products from the UAE and Oman, including meat and fins, and indicated that the majority of species traded were at global risk of extinction based on IUCN Red List classification. Results from the various studies undertaken suggest that these species are likely to be overexploited and that management measures will need to take into account the precautionary principle. There is an urgent need to formulate effective conservation and management plans to prevent further declines in a number of species. The data gathered can now serve as a reference to managers, fisheries scientists, and other stakeholders to prioritize future research, as well as lay foundations for the development and implementation of national management plans for the protection and conservation of sharks

Catch composition and life history characteristics of sharks and rays (Elasmobranchii) landed in the Andaman and Nicobar Islands, India

Detailed information on shark and ray fisheries in the Andaman and Nicobar Islands, India are limited, including information on the diversity and biological characteristics of these species. We carried out fish landing surveys in South Andamans from January 2017 to May 2018, a comprehensive and cost-effective way to fill this data gap. We sampled 5,742 individuals representing 57 shark and ray species landed from six types of fishing gears. Of the 36 species of sharks and 21 species of rays landed, six species of sharks (Loxodon macrorhinus, Carcharhinus amblyrhynchos, Sphyrna lewini, C. albimarginatus, C. brevipinna, and Paragaleus randalli) comprised 83.35% of shark landings, while three species of rays (Pateobatis jenkinsii, Himantura leoparda and H. tutul) comprised 48.82% of ray landings, suggesting a species dominance in the catch or fishing region. We provide insights into the biology of species with extensions in maximum size for seven shark species. Additionally, we document an increase in the known ray diversity for the islands and for India with three previously unreported ray species. We found that amongst sharks, mature individuals of small-bodied species (63.48% males of total landings of species less than 1.5 m total length when mature) and immature individuals of larger species (84.79% males of total landings of species larger than 1.5 m total length when mature) were mostly landed; whereas for rays, mature individuals were predominantly landed (80.71% males of total landings) likely reflecting differences in habitat preferences along life-history stages across species and fishing gear. The largest size range in sharks was recorded in landings from pelagic longlines and gillnets. Further, the study emphasizes the overlap between critical habitats and fishing grounds, where immature sharks and gravid females were landed in large quantities which might be unsustainable in the long-term. Landings were female-biased in C. amblyrhynchos, S. lewini and P. jenkinsii, and male-biased in L. macrorhinus and H. leoparda, indicating either spatio-temporal or gear-specific sexual segregation in these species. Understanding seasonal and biological variability in the shark and ray landings over a longer study period across different fisheries will inform future conservation and fishery management measures for these species in the Andaman and Nicobar Islands

Low genetic diversity after a bottleneck in a population of a critically endangered migratory marine turtle species

Hawksbill turtles (Eretmochelys imbricata), which are distributed throughout the world's oceans, have undergone drastic declines across their range, largely due to anthropogenic factors. Assessing sizes, genetic variability and structure of their populations at global and regional levels is critical to the development of conservation management strategies. Here, nuclear and mitochondrial markers were used to analyse patterns of parentage and population structure in hawksbill turtles in United Arab Emirates (UAE) waters, utilizing samples from two life stages (hatchlings and juveniles), and to compare the UAE population with neighboring populations. Weak genetic differentiation was detected between juveniles and hatchlings and between the nesting sites of Dubai and Sir Bu Nair. Parentage analysis suggested that only 53 females and 74–80 males contributed to the hatchlings from 67 nests across three nesting sites in UAE (Dubai, Sir Bu Nair, Abu Dhabi). No females were identified as nesting in more than one location. In Dubai and Abu Dhabi, single paternity was the norm (75%), whereas on Sir Bu Nair, multiple paternity was detected in the majority of nests (67%). Polygyny was also frequently detected on Sir Bu Nair (15% of the overall number of males), but not in the other nesting sites. Comparison of the UAE population with published data from other populations suggests that population structure exists both within the Gulf and between the Gulf and Indian Ocean populations, and that the UAE population has lower genetic variability than the Seychelles population. Finally, the data suggest that the UAE population, and the Gulf population overall, experienced a bottleneck/founder event. The observed overall low genetic variability, evidence of population structure in the Gulf, and strong differentiation between the Gulf and the Indian Ocean populations, raises concerns about the sustainability of this species in this near-enclosed basin. These results highlight the need for regional collaboration in the development of management measures for the long-term conservation of this Critically Endangered specie

Spotted Guitarfish Rhinobatos punctifer

The Spotted Guitarfish (Rhinobatos punctifer) occurs from the northern Red Sea to Sea of Oman and Arabian Gulf/Persian Gulf (hereafter referred to as the 'Gulf') to depths of 70 m. Due to previous misidentification with the Bengal Guitarfish (Rhinobatis annandalei), accurate information on the species is limited. Guitarfish are commonly caught in gillnet, trawl and line fisheries throughout the region, but specific threats to this species are poorly known due to the lack of information on distribution and fisheries data. Declines of several species of inshore guitarfish have been documented within the region and present levels of catches are of concern with fishing pressure increasing. Furthermore, the loss and modification of coastal habitats in the Gulf is a significant concern for inshore species such as this. A decline of <30% is suspected across its range due to current levels of fishing, which is ongoing and suspected to result in a future decline over the next three generation periods (2017-2032). The species is therefore assessed as Near Threatened (nearly meeting VU A2d+3d). Further investigation of this species is required to accurately define its range, biology, extent of catches in local fisheries and levels of declines. This assessment should be revisited as soon as this is available

Troubled Waters: Threats and Extinction Risk of the Sharks, Rays and Chimaeras of the Arabian Sea and Adjacent Waters

The extinction risk of sharks, rays and chimaeras is higher than that for most other vertebrates due to low intrinsic population growth rates of many species and the fishing intensity they face. The Arabian Sea and adjacent waters border some of the most important chondrichthyan fishing and trading nations globally, yet there has been no previous attempt to assess the conservation status of species occurring here. Using IUCN Red List of Threatened Species Categories and Criteria and their guidelines for application at the regional level, we present the first assessment of extinction risk for 153 species of sharks, rays and chimaeras. Results indicate that this region, home to 15% of described chondrichthyans including 30 endemic species, has some of the most threatened chondrichthyan populations in the world. Seventy-eight species (50.9%) were assessed as threatened (Critically Endangered, Endangered or Vulnerable), and 27 species (17.6%) as Near Threatened. Twenty-nine species (19%) were Data Deficient with insufficient information to assess their status. Chondrichthyan populations have significantly declined due to largely uncontrolled and unregulated fisheries combined with habitat degradation. Further, there is limited political will and national and regional capacities to assess, manage, conserve or rebuild stocks. Outside the few deepsea locations that are lightly exploited, the prognosis for the recovery of most species is poor in the near-absence of management. Concerted national and regional management measures are urgently needed to ensure extinctions are avoided, the sustainability of more productive species is secured, and to avoid the continued thinning of the regional food security portfolio

Putting sharks on the map: A global standard for improving shark area-based conservation

Area-based conservation is essential to safeguard declining biodiversity. Several approaches have been developed for identifying networks of globally important areas based on the delineation of sites or seascapes of importance for various elements of biodiversity (e.g., birds, marine mammals). Sharks, rays, and chimaeras are facing a biodiversity crisis with an estimated 37% of species threatened with extinction driven by overfishing. Yet spatial planning tools often fail to consider the habitat needs critical for their survival. The Important Shark and Ray Area (ISRA) approach is proposed as a response to the dire global status of sharks, rays, and chimaeras. A set of four globally standardized scientific criteria, with seven sub-criteria, was developed based on input collated during four shark, biodiversity, and policy expert workshops conducted in 2022. The ISRA Criteria provide a framework to identify discrete, three-dimensional portions of habitat important for one or more shark, ray, or chimaera species, that have the potential to be delineated and managed for conservation. The ISRA Criteria can be applied to all environments where sharks occur (marine, estuarine, and freshwater) and consider the diversity of species, their complex behaviors and ecology, and biological needs. The identification of ISRAs will guide the development, design, and application of area-based conservation initiatives for sharks, rays, and chimaeras, and contribute to their recovery

Scoliodon laticaudus, Spadenose Shark

The Spadenose Shark (Scoliodon laticaudus) is a small (to 91 cm total length) shark that occurs in the northern Indian Ocean from the Gulf of Oman to Myanmar. It is common in coastal and estuarine waters at depths of 10-75 m, but more typically less than 50 m and prefers muddy and sandy substrates and often occurs near large freshwater outflows. It is highly productive with annual large litters of 6–20 pups, early maturation at two years and a short generation length of 4.5 years. The species is caught mainly by trawl and gillnet in industrial and artisanal fisheries and is retained for human consumption. It is the dominant shark landed in Pakistan, northern India, and Bangladesh and fishing pressure is intenseacross most of its range. The high productivity of the species and short generation length likely provide it with resilience to fishing pressure, however, the intense and ongoing fishing pressure on this species is a cause for concern. It is suspected that the Spadenose Shark has undergone a population reduction of 20–29% over the past three generation lengths (14 years) and is close to reaching the population reduction threshold due to levels of exploitation, and it is assessed as Near Threatened (nearly meeting Vulnerable A2d)

Rhinobatos annandalei, Bengal Guitarfish

The Bengal Guitarfish (Rhinobatos annandalei) is a small (to 95 cm total length) guitarfish that occurs in the northern Indian Ocean from the United Arab Emirates (UAE) to Bangladesh, including Sri Lanka. The western boundary of this species distribution is uncertain due to confusion with the Spotted Guitarfish (R. punctifer). It is demersal on the inner continental shelf at depths of 5–73 m. The species is mainly a bycatch of a range of industrial and artisanal gears including demersal trawls, longlines, and gillnets. The meat is consumed locally and traded internationally, and the skins are exported from Bangladesh to Myanmar to be made into accessories (e.g. handbags). There is a high level of fisheries resource use and increasing fishing pressure across the range of this species. Severe population reduction is inferred from actual levels of exploitation, as well as several historical accounts and contemporary datasets from the UAE, Iran, Pakistan, and India. Landings data of guitarfishes and rays from the UAE, Iran, Pakistan, India, and Bangladesh indicate landings declines of 69–93% consistent with population reductions of 80% over the past three generation lengths (27 years). These levels of declines are not species-specific but are informative for understanding the broader levels of guitarfish decline in the region. It is suspected that the Bengal Guitarfish has undergone a population reduction of >80% over the past three generation lengths (27 years) due to actual levels of exploitation, and it is assessed as Critically Endangered A2d

Carcharhinus hemiodon Pondicherry Shark

The Pondicherry Shark (Carcharhinus hemiodon) is a small (to 102 cm total length) and very rare Indo- West Pacific whaler shark. It has a wide historic range from Oman to southern China, but known records are scattered, and it has only been reliably verified from a handful of countries. It appears to occur in shallow coastal waters, and has also been reported to enter rivers, although this has not been verified. The contemporary range of this species is poorly defined and museum specimens were collected pre- 1960. There are reports from 1979, the 1990s, and 2000, but none of these could be verified. Its identification is problematic, and it is easily confused with a number of other Carcharhinus species (for example, recent putative records from Sri Lanka)

Overfishing and Habitat Loss Drives Range Contraction of Iconic Marine Fishes to Near Extinction

Extinctions on land are often inferred from sparse sightings over time, but this technique is ill-suited for wide-ranging species. We develop a space-for-time approach to track the spatial contraction and drivers of decline of sawfishes. These iconic and endangered shark-like rays were once found in warm, coastal waters of 90 nations and are now presumed extinct in more than half (n = 46). Using dynamic geography theory, we predict that sawfishes are gone from at least nine additional nations. Overfishing and habitat loss have reduced spatial occupancy, leading to local extinctions in 55 of the 90 nations, which equates to 58.7% of their historical distribution. Retention bans and habitat protections are urgently necessary to secure a future for sawfishes and similar species