Troubled waters : Threats and extinction risk of the sharks , rays and chimaeras of the Arabian Sea and adjacent waters

Rima W. Jabado1,2 | Peter M. Kyne3 | Riley A. Pollom4 | David A. Ebert5 | Colin A. Simpfendorfer6 | Gina M. Ralph7 | Shaikha S. Al Dhaheri1 | K. V. Akhilesh8 | Khadeeja Ali9 | Mohamud Hassan Ali10 | Tariq M. S. Al Mamari11 | K. K. Bineesh12 | Igbal S. El Hassan13 | Daniel Fernando14,15 | Edwin M. Grandcourt1 | Muhammad Moazzam Khan16 | Alec B. M. Moore17 | Fereidoon Owfi18 | David P. Robinson19 | Evgeny Romanov20 | Ana-Lucia Soares2 | Julia L. Y. Spaet21 | Dawit Tesfamichael22 | Tooraj Valinassab23 | Nicholas K. Dulvy4


| INTRODUC TI ON
Sharks and their relatives, including rays and chimaeras, are collectively termed chondrichthyan fishes and comprise one of the three classes of fishes (Class Chondrichthyes). Chondrichthyans are a relatively small lineage of approximately 1,250 currently described species (Eschmeyer, Fricke, & van der Laan, 2017) of an evolutionarily distinct conservative group that has functioned successfully in diverse aquatic ecosystems for over 400 million years (Compagno, 1990;Stein et al., 2018). Despite their evolutionary success, there is growing evidence that many species are increasingly threatened with extinction as a result of their conservative life-history traits that make them particularly susceptible to population decline from overfishing and habitat degradation (Dulvy et al., 2008(Dulvy et al., , 2014Kyne & Simpfendorfer, 2010;Stevens, Bonfil, Dulvy, & Walker, 2000).
Although there is considerable variation among species, many chondrichthyans grow slowly, mature relatively late, have a small number of young and have a low natural mortality (Stevens et al., 2000). These characteristics result in very low rates of population increase with little capacity to recover from overfishing, and habitat loss and degradation (Cortés, 2016;Dulvy et al., 2014;Pardo, Kindsvater, Reynolds, & Dulvy, 2016).  (2017)). Fisheries resources in the region are under extreme pressure with several teleost species thought to be fully or over-exploited with reported declines between 40% and 80% in the last 15-20 years (De Young, 2006;Flewwelling & Hosch, 2006;Grandcourt, 2012;Jin, Kite-Powell, Hoagland, & Solow, 2012;Mohamed & Veena, 2016). Within the same period, there has been growing demand for sharks for food security through the provision of animal protein as well as to supply the fin trade, and as a result, fishing effort has increased in traditional shark fisheries (Ali & Sinan, 2014;Bonfil, 2003;Henderson, McIlwain, Al-Oufi, & Al-Sheili, 2007;. The Arabian Sea and adjacent waters are now recognized as one of the regions of the world with the largest number of chondrichthyan fishers and traders (Dent & Clarke, 2015;Dulvy et al., 2017;Jabado & Spaet, 2017;Jabado, Al Ghais, Hamza, Henderson, Spaet, et al., 2015).
Performance analyses reveal that International Union for Conservation of Nature (IUCN) Red List of Threatened Species Criteria are closely aligned to and in harmony with fisheries reference points Fernandes et al., 2017;Porszt, Peterman, Dulvy, Cooper, & Irvine, 2012). Here, we present results from the first regional assessment of extinction risk of all chondrichthyans in the Arabian Sea and adjacent waters. We aim to (a) evaluate the status of all species using a consistent methodology; (b) identify the major threatening processes that chondrichthyans face in the region; and (c) recommend priority areas for future research, policy actions and appropriate management interventions needed to ensure the long-term survival of these species.

| MATERIAL S AND ME THODS
We first delineate the taxonomic scope and standards of our assessment, before summarizing the IUCN Red List of Threatened Species assessment approach, and the mapping of species distributions.

| Taxonomic scope
The nomenclature and authorities used for chondrichthyans follow those of the online electronic version of the Catalog of Fishes (Eschmeyer et al., 2017)

| Application of the IUCN Red List Categories and Criteria
The IUCN Red List Categories and Criteria (version 3.1) and Guidelines for Application of IUCN Red List Criteria at Regional and National Levels (version 4.0) were applied to the 153 species occurring in the Arabian Sea and adjacent waters (IUCN, 2012(IUCN, , 2016 These categories are used unaltered at the regional level with a few adjustments to account for connectivity with adjacent populations outside the assessment region (IUCN, 2012). A species is Regionally Extinct (RE) if there is no reasonable doubt that the species is extinct in the region, but exists elsewhere in the wild. A species qualifies for NA if it is deemed ineligible for assessment at the regional level (e.g. it is not within its natural range in the region, is a vagrant to the region, or occurs at very low numbers in the region). The proportion of species in each of the IUCN Red List Categories was calculated and is summarized in Table 1.

| Species mapping
Generalized distribution maps were produced for each species using ArcMap 10.1 (ESRI, 2014), based on known and inferred occurrences. Coastal species maps were generated using a standardized polygon that is either the 200-m isobath or 100 km from the shoreline, whichever is further from the coast. Maps for the oceanic species were digitized by hand using depth and habitat preferences as a broad guide. The maps were first drafted based on regional and global guides (i.e. Adam, Merrett, & Anderson, 1998;Almojil, Moore, & White, 2015;Anderson & Ahmed, 1993;Bianchi, 1985;Bonfil & Abdallah, 2004;Compagno, 2001;De Silva, 2015;Ebert, Fowler, & Compagno, 2013;Jabado & Ebert, 2015;Last & Stevens, 2009;Last et al., 2016;Raje et al., 2007). These were augmented with speciesspecific records from the literature (including unpublished fisheries and scientific reports) and with photographic records provided by experts at the workshop. Draft maps were reviewed during the workshop and subsequently vetted by taxonomic and regional experts. To determine diversity patterns, maps of regional species richness as well threatened (CR, EN and VU categories), DD and endemic species richness maps were produced. water and freshwater) mainly according to depth distribution and, to a lesser degree, position in the water column (see Dulvy et al., 2014 for details). Upper and lower depth bounds were plotted according the IUCN Red List Categories assigned to each species. Regional threats known to have major impacts on species were coded, although their relative importance for each species was not described.

| Major threats and species habitat classifications
The principal drivers of decline and local extinction risk were then evaluated and summarized for species considered threatened.

| Species diversity
An estimated 184 chondrichthyan species are reported from the Arabian Sea and adjacent waters, representing 15% of valid described chondrichthyans globally (Eschmeyer et al., 2017).

| Trends in regional chondrichthyan landings
Chondrichthyan population declines in the Arabian Sea and adjacent waters were attributed to several factors, including fishing activities and the effects of habitat loss and environmental degradation ( Figure 1). Although there is an increasing number of fishery-dependent surveys in the region, there was a real paucity of published trend information on fisheries catches and reliable species-specific landings data, particularly in the western part of the region in Djibouti, Egypt, Eritrea and Somalia. However, anecdotal evidence along with the available regional data supported largescale declines in populations of many species. Below, we provide some examples of these declines from various countries.
In Pakistan, data from tuna gillnet vessels, which land approximately 55% of sharks, exhibited an 80% decline in shark landings from 22,471 t in 2002 to 4,660 t in 2011 (Moazzam, 2012 The primary threats driving chondrichthyans to extinction in the Arabian Sea and adjacent waters based on the proportion (dark grey) and number (light grey) of threatened species (Critically Endangered, Endangered and Vulnerable) impacted by the threat class.
The "all use" category refers to both "intentional" mortality and "incidental" mortality 5 years from 13,000 t in 1994 to 9,000 t in 1999 and were steadily declining since 2001 despite increasing effort (Dissanayake, 2005).
De Silva (2006) noted that some species of reef-associated sharks such as the Zebra Shark (Stegostoma fasciatum, Stegostomatidae),

Tawny Nurse Shark (Nebrius ferrugineus, Ginglymostomatidae)
and Whitetip Reef Shark (Triaenodon obesus, Carcharhinidae) had become very rare in Sri Lankan waters due to overfishing. In the Maldives, shark populations were showing signs of decline in the early 1980s and many reef shark stocks in the northern atolls were reportedly overfished while oceanic stocks showed reduced catches (Ali, 2015). Results from interviews with fishermen in the UAE ("Gulf") and Eritrea (Red Sea) highlighted that fishers had seen significant declines in the abundance of sharks over the past two decades Tesfamichael, Pitcher, & Pauly, 2014). In Eritrea, these patterns of decline in "best" catch rates recorded from fishers (10.3% per year) (years where they landed the largest quantities) were similar to those observed using appraisal methods such as ecosystem modelling (11% per year) (Tesfamichael et al., 2014). Data from the monitoring of fish landing sites in Oman, Saudi Arabia (Red Sea) and the UAE indicated that shark fisheries were heavily exploited with larger, slower-growing species being replaced by smaller, faster-growing species over time (Henderson et al., 2004;Jabado et al., 2016;Spaet & Berumen, 2015). Reports from Iran based on a comparison of results from fisheries-independent trawl surveys in the "Gulf" indicated that the biomass of sharks (particularly whaler sharks, Carcharhinidae) had been decreasing since the 1970s (Valinassab et al., 2006). Whaler sharks (Carcharhinidae, mostly Carcharhinus spp.) comprised up to 22% of biomass in 1980-1981, yet 20 years later in 2002, they represented only ~2% (Sivasubramaniam, 1981;Valinassab et al., 2006).

| Extinction risk
Of the 153 chondrichthyan species assessed, 78 species (50.9%) were classified as threatened (Table 1). These species face an extremely high risk of extinction in the wild (CR: 9.2%), a very high risk of extinction in the wild (EN: 22.2%) or a high risk of extinction in the wild (VU: 19.6%). Twenty-seven species (17.6%) were considered NT.
Nineteen species (12.4%) were LC and not considered to be at risk of extinction now or in the foreseeable future. For 29 species (19%), there was insufficient or inadequate information available on their distribution or abundance to make a direct or indirect assessment of their status and these were classified as DD. Of these DD species, 17 were only known from a few records with limited data on their biology and distribution.
Most threatened species were assessed under Criterion A (93.5%, n = 78 of 153), which is based on the rate of population decline over the longer time frame of three generation lengths (the median age of parents of the current cohort) or 10 years (IUCN, 2016). This is primarily because the main source of population trend data for chondrichthyans in the region is derived from catch or landings data, and fishery-dependent surveys. The remaining threatened species were assessed using the IUCN geographic range Criterion B (n = 2: Aden Torpedo and Red Sea Torpedo (Torpedo adenensis and T. suessi, Torpedinidae)), or the small population size and decline Criterion C (n = 3: Whale Shark (Rhincodon typus, Rhincodontidae), Pondicherry Shark (Carcharhinus hemiodon, Carcharhinidae) and Ganges Shark (Glyphis gangeticus, Carcharhinidae)). No species were assessed under Criteria D or E, as sufficient data to support the presence of a very small or restricted population, and for a fully quantitative assessment (e.g. population viability analysis), were not available.

| Status by major taxonomic group
Of Efforts were made to place species into a category other than DD, and these assessments were mostly due to species with a limited number of records, limited geographic distribution and no information on their interaction with fisheries, resulting in a reduced capacity to evaluate their status. For example, the Arabian Catshark (Bythaelurus alcockii, Scyliorhinidae) is only known from one specimen caught in the Arabian Sea off Pakistan at a depth of over 1,000 m and its holotype is most likely lost (Compagno, 1990).
The Bluespotted Maskray (Neotrygon caeruleopunctata, Dasyatidae) was only recently confirmed from the region, and its current taxonomic uncertainty limits a full understanding of the species' range and regional occurrence (Last et al., 2016). Families containing only DD species include the sleeper sharks (Somniosidae), bullhead sharks (Heterodontidae) and lantern sharks (Etmopteridae), each with two species (Figure 4). For the rays, the deepwater stingray (Plesiobatidae) and sixgill stingray (Hexatrygonidae) were also DD.

| Spatial analyses
Species richness was highest in nearshore areas throughout the re-   (Dulvy, Allen, Ralph, & Walls, 2016). This regional extinction risk proportion is higher than the global assessment where one-quarter of chondrichthyans were predicted to be threatened (24%) (Dulvy et al., 2014). It has been recognized that certain locations have lower extinction risk at the regional scale

| Threatened species: the need for immediate action
Some of the families considered threatened encompass a disproportionately large amount of evolutionary distinctness (Stein et al., 2018). Of these, the sawfishes (Pristidae) have received the most attention in recent years, with remaining populations considered small and fragmented (Dulvy, Davidson, et al., 2016;Elhassan, 2018

| Least Concern species: food security opportunities
Many of the families dominated by LC species have low diversity (represented by one or two species), have limited geographical distributions and/or occur in the deepsea beyond the current range of intensive fisheries. These have a limited regional range in shallow inshore waters with scarce data on their biology but are mostly

| Data Deficient species: addressing knowledge gaps
Patterns of data deficiency in certain species groups should be used to prompt research initiatives across the region. Indeed, Data Deficient listings highlight the need for additional data collection, with the possibility that some species may meet threatened criteria with a better understanding of threats and their populations. This is especially true as many DD species occur within the range of expanding deepsea fisheries that may quickly begin to threaten them  to 900 t/year and effort from approximately 420 to 1,600 standardized trips/year (Tsehaye, Machiels, & Nagelkerke, 2007). In India, the mechanization of fishing fleets increased by 57% between 1960 and 1990, contributing to a situation of over-capacity and overfishing (Mohamed & Veena, 2016).

| Emerging trends: deepsea fisheries
The development and rapid expansion of intense deepsea fishing is a growing concern especially in the south-eastern Arabian Sea. Gulper shark stocks (Centrophorus spp., Centrophoridae) off the Maldives  Akhilesh et al., 2011). These stock declines within a short period of time after the beginning of their exploitation demonstrate that the limited biological productivity of Centrophorus spp. restricts their ability to sustain directed or by-catch fishing pressure and makes them highly susceptible to overexploitation (Ali & Sinan, 2014;Garcia, Lucifora, & Myers, 2008;Graham, Andrew, & Hodgson, 2001;Simpfendorfer & Kyne, 2009).
Although the gulper shark fishery has ceased off the Maldives, given their life-history population recovery is expected to be very slow (Simpfendorfer & Kyne, 2009 (Compagno, Dando, & Fowler, 2005;Springer, 1968) and does not appear to currently interact with fisheries. However, as marine fish stocks from nearshore waters off the south-eastern Arabian Sea are heavily exploited, it is likely that fisheries will continue to expand into deeper water with likely incursions into waters outside national EEZs, putting many species under pressure.

| Foreign fleets and pelagic fisheries
In addition to national fisheries, foreign fleets operate in the EEZs of many countries. Considering the warning signs of elevated extinction risk and the small number of species assessed as LC, food security in the region is jeopardized. These concerns are exacerbated by most countries in the region that allow, or have previously allowed, access rights to foreign fleets to operate in their waters (Jabado & Spaet, 2017). Accurate numbers of vessels operating in each countries' territorial waters are not available, but most reports suggest that illegal respectively, and steadily decreased to <50 t by the end of fisheries reflecting decreased fishing effort and the shifting of targeting from demersal fish to small pelagics (Romanov & Kukharev N.N., unpubl. data).
At least 400 longline vessels and purse seine fleets from countries in the European Union, as well as China, Japan, South Korea and Taiwan, are active in the waters of the north-west Indian Ocean (IOTC, 2013). Pelagic fisheries have operated in the Indian Ocean for more than 50 years with Japanese longliners in the western region since 1954 (Honma & Suzuki, 1972). Taiwanese, USSR and South Korean vessels have fished there since ~1956, 1964~1956, and 1966~1956, , respectively (Borodatov, 1968NMFS, FSFRL 1980). The introduction of large-scale tuna purse seine fisheries in 1982 also increased pressure on pelagic sharks, in particular those associated with fish aggregation devices (FADs) (Filmalter, Capello, Deneubourg, Cowley, & Dagorn, 2013;Romanov, 2002Romanov, , 2008

| Habitat modifications
It is clear that modifications to the natural environment are affecting a variety of species, particularly small coastal sharks and rays, as well as large species that use inshore habitats for breeding and nursery functions (e.g. Jennings, Gruber, Franks, Kessel, & Robertson, 2008). Across the Arabian Sea and adjacent waters, marine habitats have experienced high levels of disturbance and are quickly deteriorating in quality due to major impacts from anthropogenic activities. Red Sea coral cover has markedly declined in the last 30 years, mirroring increased coastal construction (Price et al., 2014). In the "Gulf," major impacts on marine habitats have been documented with the removal of shallow productive areas due to rapid large-scale residential and commercial coastal development, desalination plants, chronic and acute releases of oil (e.g. war-related), and the damming of the Tigris-Euphrates river system (Sheppard et al., 2010). For example, coastal seafilling (sometimes referred to as "land reclamation") has resulted in the almost total loss of mangrove areas around Bahrain (Morgan, 2006). In the broader Arabian Sea, intensive bottom trawling has reduced the complexity of benthic habitats, affecting the epiflora and epifauna and likely reducing the availability of suitable habitats for predators and prey (Bhagirathan et al., 2014;Kaisser, Collie, Hall, Jennings, & Poiner, 2002;Stevens, Walker, Cook, & Fordham, 2005). The Indus River, one of the few estuaries in the Arabian Sea and adjacent waters, has been severely impacted by riparian habitat degradation and pollution (including untreated discharge from industrial and chemical plants), increasing river use, sand mining and the construction of dams and barrages, which have fragmented the habitat, altered flow and affected river productivity (Braulik, Noureen, Arshad, & Reeves, 2015).
Fishermen across the region target shark and ray breeding aggregations and nursery areas, and land high volumes of juveniles of various species including Scalloped Hammerhead (Sphyna lewini, Sphyrnidae) and Silky sharks leading to concerns about the potential effects on targeted species (Bonfil, 2003;Henderson et al., 2007;Spaet & Berumen, 2015). Furthermore, some species, such as the Ganges shark, listed as Critically Endangered, have high habitat specificity to estuaries and rivers, which increases their susceptibility to the impacts of human activities. However, mating and nursery areas have not been defined for most species and critical habitats, particularly for offshore, open water, and deepsea species, are virtually unknown.

| Regional chondrichthyan management
While there has been progress with chondrichthyan management in the region, it remains poorly developed and inconsistent across countries due to stark differences in governance capacity and available data with which to inform policy (De Young, 2006;Pitcher, Kalikoski, Pramod, & Short, 2009). Fisheries in most of the region are managed by input and output controls developed for teleost fisheries, and yet, some have either fully banned the fishing of sharks and/ or rays (e.g. Maldives, Saudi Arabia, Sudan) or protected several species (e.g. India, Pakistan, Sri Lanka, UAE) (Ali, 2015;Jabado & Spaet, 2017;Kizhakudan et al., 2015). However, fisheries monitoring is so limited that it is difficult to evaluate whether these measures have been successful. In fact, effective enforcement is a challenge and an ongoing issue for most countries, political will appears to be weak, and current restrictions appear to be inadequate to ensure the longterm survival of many species and populations (see details in Jabado, Kyne, et al., 2017;Jabado & Spaet, 2017).
Regional Fisheries Bodies (RFBs) across the region have generally not adopted or developed actions for chondrichthyan fisheries (Fischer, Erikstein, D'Offay, Guggisberg, & Barone, 2012;Jabado & Spaet, 2017). Other RFBs, such as the Regional Commission for Fisheries, Regional Organization for the Protection of the Marine Environment and the Regional Organization for the Conservation of the Environment of the Red Sea and Gulf of Aden, have yet to adopt any measures for the conservation and management of sharks (Jabado, Kyne, et al., 2017;Jabado, Al Baharna, et al., 2017). International measures developed through various agreements to ensure sustainable catches, collection of species-specific fisheries data, special protections for threatened species, trade controls and the conservation of biodiversity are slowly being recognized (Fischer et al., 2012;Mundy-Taylor et al., 2014

| Future directions and recommendations
Chondrichthyan fisheries are of increasing economic and commercial importance in the Arabian Sea and adjacent waters primarily for food security through the provision of animal protein and income from the trade of products such as fins, meat, liver oil, gill plates (Mobulidae) and leather. This is particularly true as most teleost fisheries are over-exploited and chondrichthyans are becoming a valued by-catch of traditional fisheries, with increased retention of all species of sharks and rays (Clarke et al., 2006;Jabado & Spaet, 2017;Lack & Sant, 2011). This demand for fish is expected to increase given the growing animal protein needs, especially in developing countries (Mora et al., 2009). In parallel, populations of some chondrichthyan species in the Arabian Sea and adjacent waters have been so reduced that the only way to rebuild them, and avoid collapse with great certainty, is to shut down major fisheries until stocks are rebuilt to healthy levels. Even if this were possible, recovery would be slow because once collapsed, most fish populations do not recover rapidly, if at all (Hutchings & Reynolds, 2004 focuses on protecting species with the lowest biological productiv- ity. Yet, comprehensive management and recovery strategies require a good understanding of species behaviour, habitat, ecology and evolution, which affect population growth at low abundances (Hutchings & Reynolds, 2004 The continued discovery of new chondrichthyan species within the region, and the need for resolution of taxonomic issues related to even some of the most well-known species, reinforces that research needs to be not only sustained, but increased in the fundamental fields of taxonomy, systematics, life history, ecology and fisheries. The challenge for nations bordering the Arabian Sea and adjacent waters will be to ensure that precautionary policies are developed and protections are enforced. Indeed, it is often stipulated that fisheries management monitoring, implementation and effectiveness are affected by the economic and development status of a country, with high-income or high-development status countries, having significantly better fisheries management than low-income countries (Davidson et al., 2015;Gutierrez, Hilborn, & Defeo, 2011;Mora et al., 2009;Pitcher et al., 2009), but this might not be the case in the Arabian Sea and adjacent waters. The region is surrounded by some of the richest and poorest nations in the world, and yet, we could argue that the lower-and middle-income economies here have at the least better fisheries monitoring and policy development (Jabado & Spaet, 2017). Indeed, while countries surrounding the "Gulf" and bordering half of the Red Sea have high human development indexes, they remain data-poor due to little survey efforts, as well as a lack of infrastructure to monitor and report chondrichthyan catches (Jabado & Spaet, 2017;UNDP, 2016 Data collection and availability are an essential precursor to fisheries management, and we noted several challenges in compiling and analysing fisheries data from this region. First, we found that additional fisheries time-series data sets were available to certain workshop participants that had not been previously made public and disseminated. These showed important declines in batoids and the collapse of many carcharhinid species. Our results should serve to raise red flags calling for conservation actions while there remains a chance of recovery for some species and the prevention of permanent biodiversity loss. Despite long-standing warnings about population declines (e.g. Bonfil, 2003;Devadoss, Kuthalingam, & Thiagaranjan, 1989;Henderson et al., 2007;Valinassab et al., 2006), there is still no mechanism in place to ensure the funding, develop- 7. Initiate the development of National Plans of Action for the Conservation and Management of Sharks along with a Regional Shark Plan specifically aimed at increasing cooperation between countries in relation to the conservation and sustainable use of commercially exploited and by-caught chondrichthyans; 8. Establish and enforce MPAs with no-take zones to ensure they provide adequate protection to threatened species, and to alleviate pressure on certain nonmigratory species and on the critical habitats (e.g. breeding and nursery areas, feeding grounds) that are necessary for their conservation; 9. Ensure that the assessment and consenting (e.g. Environmental Impact Assessment process) of marine and coastal developments adequately consider project-specific and cumulative impacts of habitat loss and modification on chondrichthyan species; 10. Implement catch limits in accordance with scientific advice and when sustainable catch levels are uncertain, implement fishing limits based on the precautionary approach; 11. Strengthen finning bans, if applicable, by requiring all sharks taken in all fisheries to be landed with their fins still naturally attached; 12. Propose and work to secure science-based chondrichthyan conservation measures nationally and within RFMOs, especially for fisheries that target or affect species assessed as threatened or NT; and, 13. Engage with RFMOs to fully document fisheries including mapping of areas fished and fishing effort deployed through observer programmes or technologies such as vessel monitoring systems.
Research 1. Develop and facilitate training, particularly in the fields of taxonomy and population monitoring methods (to enable the accurate collection of species-specific landings data) and stock assessment; 2. Collect fisheries-dependent data on artisanal and commercial fisheries, especially data on catch composition, by-catch, landings, discards and catch per unit effort; 3. Improve knowledge of species by expanding fisheries-independent monitoring (especially for threatened and DD species), and ensure that such data are shared with relevant scientific bodies and RFMOs; 4. Conduct basic biological research for deepsea and DD species, particularly those that are commercially exploited; 5. Assess population status and safe fishing levels for chondrichthyan populations through stock assessments and ecological risk assessments with priority given to heavily fished, unassessed populations; 6. Promote research on gear modifications and fishing methods aimed at mitigating chondrichthyan by-catch and discard mortality; 7. Encourage research aiming at identifying and mapping of critical habitats in the region; 8. Establish monitoring schemes for small-scale artisanal and recreational fisheries; 9. Improve species identification for those taxa with threatened species and taxonomic problems, in all data collection activities (including both commercial landings and scientific surveys). This can be achieved through the provision of species identification training to fishers, observers and researchers; and, to publish available information on fisheries catches and make these data available to allow for in-depth analysis of the current status of species. Second, for many countries, when data were available, species-specific information was difficult to obtain for certain species groups with landings reported in aggregate form. At last, the data available were mostly less than three decades old; therefore, maximum reductions over that time frame are likely underestimates, as true historic maxima will have occurred well before fisheries management agencies began collecting data on species abundance (Hutchings & Reynolds, 2004). This limited data availability suggests that impacts on chondrichthyan populations in the region and reductions in stocks could in fact be much greater than reported here. This highlights the importance of effective fisheries monitoring and data dissemination moving forward.
At last, results from these assessments provide an important baseline for monitoring the regional status of chondrichthyans and indicate that encouraging improvements to our knowledge base through concerted research and monitoring should be a priority. It is clear that it is possible to draw together a network of researchers from the region and improve collaboration and engagement.
Coalitions now need to further include policy and decision-makers to regulate the exploitation of already depleted stocks and improve enforcement mechanisms. In the light of this newly collated information on chondrichthyans in the Arabian Sea and adjacent waters, a series of governance measures and research priorities that could support the conservation and management of chondrichthyans in the region are proposed in Table 2. This is not meant to be an exhaustive list of recommendations, but any progress made on these actions is likely to deliver conservation benefits to the most threatened species. The highest priorities should be directed at reducing fishing pressure and habitat loss by strengthening law enforcement and building the capacity of local communities to pursue sustainable livelihoods along coastal areas. The future of threatened chondrichthyans in the Arabian Sea and adjacent waters rests in the willingness and the ability of individual countries to take actions in their national waters but also to collaborate with neighbouring nations.

ACK N OWLED G EM ENTS
We would like to thank the management at the Environment Agency,