Article

Elasmobranch fisheries in the Arabian Seas Region: Characteristics, trade and management

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract and Figures

The Arabian Seas Region plays an important role in the global landings and trade of sharks and rays. The United Arab Emirates (UAE) and Yemen, two countries with stark socioeconomic differences, serve as major regional trade hubs for shark and ray products and four countries (Oman, Pakistan, UAE and Yemen) supply nearly 11% of dried fin exports to Hong Kong. Yet, little information is available on the characteristics of this trade and the fisheries contributing to it. Here, we review the fisheries characteristics , trade, utilization and distribution chain of sharks and rays in 15 countries of the Arabian Seas Region based on published and grey literature, landing surveys, field observations and interviews with fishermen and traders. Although regional shark fisheries remain mostly artisanal, reported shark and ray landings represent 28% of the regional total fish production, reaching 56,074 mt in 2012 (7.3% of total world catches), with Iran, Oman, Pakistan and Yemen ranking as the primary catchers. Utilization and distribution patterns are complex, vary between landing sites and countries, and remain unmonitored. Based on widespread over-exploitation of most teleost fisheries, current exploitation levels for most sharks and rays are potentially unsustainable. The situation is exacerbated by limited research and political will to support policy development, the incomplete nature of fisheries data, as well as insufficient regulations and enforcement. A better understanding of shark and ray fisheries will be key for regulating trade, promoting conservation and developing management initiatives to secure food security, livelihoods and biodiversity conservation in the region. K E Y W O R D S chondrichthyans, conservation, extinction risk, fin trade, fisheries management, sustainability
Content may be subject to copyright.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Within the Gulf of Aden (Africa), elasmobranchs are an important component of the artisanal fishery and they are caught to be exported or sold for local consumption (Bonfil, 2003;Henderson et al., 2007;Spaet and Berumen, 2015;Jabado and Spaet, 2017). A great proportion of shark catch is from small-scale fisheries from Djibouti, Saudi Arabia, Yemen, Somalia, and Eritrea, and do not appear in any fishery statistics or record (Gladstone et al., 2003;Alabsi and Komatsu, 2014;Jabado and Spaet, 2017). ...
... Within the Gulf of Aden (Africa), elasmobranchs are an important component of the artisanal fishery and they are caught to be exported or sold for local consumption (Bonfil, 2003;Henderson et al., 2007;Spaet and Berumen, 2015;Jabado and Spaet, 2017). A great proportion of shark catch is from small-scale fisheries from Djibouti, Saudi Arabia, Yemen, Somalia, and Eritrea, and do not appear in any fishery statistics or record (Gladstone et al., 2003;Alabsi and Komatsu, 2014;Jabado and Spaet, 2017). Although several species have been recorded in this area, few of them form the bulk of these landings, which include the milk shark Rhizoprionodon acutus (Ruppell, 1837) and the scalloped hammerhead shark Sphyrna lewini (Griffith & Smith, 1834) (Bonfil, 2003;Henderson et al., 2007;Spaet and Berumen, 2015). ...
... Within the Gulf of Aden, including Djibouti, sharks are a component of the artisanal fishery and are consumed by locals (Bonfil, 2003;Henderson et al., 2007;Spaet and Berumen, 2015;Jabado and Spaet, 2017). Subsequently, pollutants accumulated in sharks might migrate to the human body through diet and results in various adverse health effects (Bosch et al., 2016). ...
... A major supplier to the international shark fin market is the northwest Indian Ocean region, with countries including the United Arab Emirates (UAE), Yemen and Oman ranked highly in terms of global landings and/or fin exports [47]. However these countries display weak overall management measures [25,42,47]. Yet shark fisheries in the region is not a recent practice, as there is evidence of their exploitation throughout human history [55]. ...
... Management of shark fisheries in the region is limited [25,42,47]. Despite calls to improve shark management plans, the response has been slow. ...
... A handful of earlier field surveys provided scant data (e.g. [11,32]), and shark landings have not been reported, underreported, or lumped together with rays [42,55]. Past field studies in the region have focused on elasmobranch populations [10,36,37,43,55,68], however these have all been conducted on time scales of a few years at most. ...
Article
Scientific knowledge is lacking on marine species of economic and conservation importance, hindering their sustainable management. Local Ecological Knowledge (LEK) has the potential to provide valuable insights on large (spatial and temporal) scales, by drawing on the collective experiences of those who work closely with the taxa of interest. This study explored the status of shark population over time in four countries across eastern and southern Arabia (i.e. Kuwait, Bahrain, Oman and Yemen). Results indicate strong declines, with highly experienced fishermen reporting greater perceived declines (80%) in the abundance of sharks (in general), with mean year of perceived decline starting in the late 1990s to early 2000s. For three specific taxa investigated, hammerhead sharks (e.g. Sphyrna mokarran) had the greatest mean perceived decline (80%), while even the group with the least decline (small carcharhinids) had mean perceived declines of 50%. Management measures are urgently required in the region to ensure sustainability of historic shark fisheries that provide food security and coastal livelihoods (e.g. Yemen and Oman), and to prevent regional extinctions (e.g. hammerhead sharks). Older and more experienced fishermen who are both; witness to the greatest declines and may have local standing and influence could be valuable resources in developing more community-based sustainable fisheries, especially given the apparent lack of success of formal management measures.
... Kyne et al. (2019) while describing the threat of extinction being faced by wedgefish and guitarfish also gave an account of their fisheries (1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011) from Sindh and Balochistan, Pakistan. Some aspects of the fisheries of these species in Pakistan were also included in studies carried out by Jabado (2018Jabado ( , 2019, Jabado and Spaet (2017) and . Gore et al. (2019) in his recent work on the elasmobranch fisheries of Balochistan also covered some aspects of fisheries guitarfish and wedgefish in province of Balochistan. ...
... These include placing sharks, rays and guitafishes on CITES Appendices or on IUCN Red List (Dulvy et al., 2014;Jabado et al., 2018;Last et al., 2016). There has been a surge on the studies focused on fisheries of elasmobranch in the Arabian Sea and contiguous sea (Chen, 1996;Dent and Clarke, 2015;Dulvy et al.,2014;Haque et al., 2018;Henederson et al., 2004;Jabado, 2018Jabado, , 2019Jabado and Ebert, 2015;Jabado and Spaet, 2017;Jabado et al., 2014Jabado et al., , 2018Karnard et al., 2020;Kyne et al., 2019;Moore, 2017). Some of these studies specifically dealt with fisheries guitarfish and wedgefish (Jabado, 2018;2019;Jabado and Spaet, 2017;Kyne et al., 2019;Moore, 2017). ...
... There has been a surge on the studies focused on fisheries of elasmobranch in the Arabian Sea and contiguous sea (Chen, 1996;Dent and Clarke, 2015;Dulvy et al.,2014;Haque et al., 2018;Henederson et al., 2004;Jabado, 2018Jabado, , 2019Jabado and Ebert, 2015;Jabado and Spaet, 2017;Jabado et al., 2014Jabado et al., , 2018Karnard et al., 2020;Kyne et al., 2019;Moore, 2017). Some of these studies specifically dealt with fisheries guitarfish and wedgefish (Jabado, 2018;2019;Jabado and Spaet, 2017;Kyne et al., 2019;Moore, 2017). Jabado and Spaet (2017) Pakistan. ...
Article
Full-text available
Guitarfish and wedgefish are commercially exploited in Pakistan (Northern Arabian Sea) since long. It is estimated that their commercial landings ranged between 4,206 m. tons in 1981 to 403 metric tons in 2011. Analysis of the landing data from Karachi Fish Harbor (the largest fish landing center in Pakistan) revealed that seven species of guitarfish and wedgefish are landed (January 2019-February 2020 data). Granulated guitarfish (Glaucostegus granulatus) contributed about 61.69 % in total annual landings of this group followed by widenose guitarfish (G. obtusus) contributing about 23.29 % in total annual landings of guitarfish and wedgefish. Annandale's guitarfish (Rhinobatos annandalei) and bowmouth guitarfish (Rhina ancylostoma) contributed 7.32 and 5.97 % in total annual landings respectively. Spotted guitarfish (R. punctifer), Halavi ray (G. halavi), smoothnose wedgefish (Rhynchobatus laevis) and Salalah guitarfish (Acroteriobatus salalah) collectively contributed about 1.73 % in total annual landings. Smoothnose wedgefish (R. laevis) is rarest of all the members of Order Rhinopristiformes. G. granulatus, G. obtusus, R. ancylostoma, G. halavi and R. laevis are critically endangered according to IUCN Red List whereas A. salalah is near threatened and R. annandalei is data deficient. There are no aimed fisheries for guitarfish and wedgefish in Pakistan but these fishes are mainly caught as by-catch of bottom-set gillnetting and shrimp trawling. Some aspects of biology of these species are also presented in the paper.
... The Arabian Sea and adjacent waters region, which encompasses the Arabian/Persian Gulf (hereby referred to as 'the Gulf'), Sea of Oman, Gulf of Aden, and Red Sea, is believed to contribute up to 20% of global reported elasmobranch production and approximately 11% of raw dried fins exported to Hong Kong (Jabado and Spaet, 2017). Within this region, only two countries report shark-like batoids in the United Nations Food and Agriculture Organization (FAO) statistics, notably Iran (174 mt of Giant Guitarfish and 10 mt of sawfish in 2014), and Pakistan (2136 mt of 'guitarfishes etc. nei' (not elsewhere included) in 2014) (FAO, 2017). ...
... Differences in sizes landed and sex ratios can be difficult to interpret as it can be due to natural sexual or spatial segregation (Sims, 2005) or a range of other factors including gear selectivity and fishing locations (Henderson et al., 2007). However, the multi-gear and multi-species fisheries in the UAE and Oman are similar and operate across available fishing grounds and in shallow depths (less than 100 m) (Carpenter et al., 1997;Henderson et al., 2007;Jabado and Spaet, 2017). Overall, the majority of specimens across species were above the smallest reported maturity sizes (Last et al., 2016a) with few neonates of any species recorded. ...
... The current fisheries management regimes in the region, combined with weak enforcement and limited technical and financial resources for monitoring and management, do not provide any protection for shark-like batoids (Jabado et al., 2017b;Jabado and Spaet, 2017). This is worrying especially in light of potentially increasing markets for elasmobranchs and their products. ...
Article
Shark-like batoids (Rhinopristiformes) represent of some of the most threatened families of sharks and rays. In certain regions, they are a relatively important component of elasmobranch fisheries, commonly taken as by-catch in gillnets and longlines, but also increasingly targeted for their high value fins and meat. This demand, combined with intense fishing pressure, has resulted in global population declines as well as localized extinctions of many rhinopristoids. Yet, information on the life-history, ecology, and conservation status remains scarce for most species. From 2010-2012, data was opportunistically collected from thirteen rhinopristoid species, including four endemic to the Arabian Sea and adjacent waters, landed from fisheries in the United Arab Emirates or transported from Oman. Four taxa dominated and comprised 92% of total shark-like batoid landings by number, namely Rhynchobatus spp., the Halavi guitarfish (Glaucostegus halavi), bowmouth guitarfish (Rhina ancylostoma), and Bengal guitarfish (Rhinobatos annandalei). Details of the biological characteristics, including size composition and sex ratios, are presented for each species. While there remain identification challenges related to some unresolved taxonomic issues, with several likely undescribed species occurring in the region, the first regional checklist of rhinopristoids is provided. Evidence of significant declines in landings combined with increasing fishing effort over a short time period raises concern about the status and long-term persistence of many species. Increased research to understand the biology, ecology, diversity, and resilience to harvest by fisheries is critical to the effective management of these species and an urgent precautionary approach to their conservation is warranted.
... However, these nets can be used to target a variety of other species in addition to tunas, including demersal sharks and rays, Spanish mackerels (Scombridae), catfish (Arius spp., Ariidae) and seabreams (Sparidae), and can be used interchangeably as a bottom-set gill nets and drift nets depending on the season and target species (Khan, 2017;Shahid, Khan, Nawaz, Abdul Razzaq, & Ayub, 2016). Vessels also frequently use multiple gears in combination, such as drift gill nets with snoods attached along the lead line or nets hung between pelagic longlines, which further complicates estimates of fishing effort (Henderson, McIlwain, Al-Oufi, & Al-Sheili, 2007;Jabado & Spaet, 2017;Winter, Rudianto, Laglbauer, Ender, & Simpfendorfer, 2020;Yulianto et al., 2018). We attempted to capture the boats more likely using drift gill nets by selecting only powered vessels for the gear types longlines, purse seines and gill nets, and two target catch categories (pelagics 30-90 cm length and pelagics larger than 90 cm). ...
... A major concern for many species in our analysis (including demersal elasmobranchs) is additional impacts from other fishing sectors not managed by the IOTC, such as the set gill net, demersal longline and bottom trawl fisheries (Georgeson et al., 2020;Jabado et al., 2018). The limited conservation and management measures under the IOTC mandate only cover incidental catches of a relatively short list of non-target species, which is especially concerning for elasmobranchs as fishing patterns shift and demand from Asian markets grows (Jabado & Spaet, 2017;WWF, 2020). Sea turtles and cetaceans are usually less marketable than elasmobranchs, but in some contexts, they have value for subsistence, bait or other traditional purposes, particularly in many coastal gill net fisheries (Temple et al., 2021). ...
... However, the lack of a common definition for FADs limits their effective management and reports indicate high rates of non-compliance across all types of fishing regulations (e.g. gear and area restrictions) within most EEZs and on the high seas(Jabado & Spaet, 2017;Kaplan et al., 2014;Swimmer, Zollett, & Gutierrez, 2020;WWF, 2020).While safe-release practices can reduce species' mortality and therefore are an important component of the by-catch mitigation portfolio, they can still have significant effects on the animal's fitness(Adams, Fetterplace, Davis, Taylor, & Knott, 2018;Wilson, Raby, Burnett, Hinch, & Cooke, 2014). Furthermore, the safe release ...
Article
Full-text available
By-catch is the most significant direct threat marine megafauna face at the global scale. However, the magnitude and spatial patterns of megafauna by-catch are still poorly understood, especially in regions with very limited monitoring and expanding fisheries. The Indian Ocean is a globally important region for megafauna biodiversity and for tuna fisheries, but has limited by-catch data. Anecdotal and scattered information indicates high by-catch could be a major threat. Here, we adapt a Productivity Susceptibility Analysis tool designed for data-poor contexts to present the first spatially explicit estimates of by-catch risk of sea turtles, elasmobranchs, and cetaceans in the three major tuna fishing gears (purse seines, longlines, and drift gill nets). Our assessment highlights a potential opportunity for multi-taxa conservation benefits by concentrating management efforts in particular coastal regions. Most coastal waters in the northern Indian Ocean, including countries that have had a minimal engagement with regional management bodies, stand out as high risk for fisheries interactions. In addition to species known to occur in tuna gears, we find high vulnerability to multiple gear types for many poorly known elasmobranchs that do not fall under any existing conservation and management measures. Our results indicate that current by-catch mitigation measures, which focus on safe-release practices, are unlikely to adequately reduce the substantial cumulative fishing impacts on vulnerable species. Preventative solutions that reduce interactions with non-target species (such as closed areas or seasons, or modifications to gear and fishing tactics) are crucial for alleviating risks to megafauna from fisheries.
... The purpose of this paper is to review the elasmobranch fauna (sharks and related species) of the Arabian/Persian Gulf (hereafter referred to as the Gulf) in the context of potential species identification issues for fishery managers. As is the case throughout most of the world, elasmobranchs are heavily fished by Gulf countries, and the current levels of exploitation are unlikely to be sustainable (Jabado and Spaet, 2017). Reducing this pressure on regional stocks will require a concerted effort by the countries involved, but the difficulties involved in collecting reliable field data must first be addressed. ...
... Shark landings in the Gulf are diverse but dominated by small-bodied carcharhinids (Carcharhinidae) such as the Milk Shark R. acutus, Grey Sharpnose Shark R. oligolinx, Sliteye Shark Loxodon macrorhinus, and Hardnose Shark Carcharhinus macloti Moore et al., 2012b;Jabado et al., 2014;Jabado and Spaet, 2017). Although all of these species exhibit useful diagnostic features (Compagno et al., 2005), they are of similar size and general appearance. ...
... The implementation of effective management measures is urgently required in order to ensure the conservation of Gulf elasmobranch stocks (Jabado and Spaet, 2017). Some taxa, such as the sawfishes (Pristidae), were once common in the region but are now functionally extinct (Moore, 2015), while landings of others continue to decline despite increasing fishing effort (Jabado, 2018). ...
Article
Species-specific biological data are commonly combined with fishery operational data to model exploited stocks and determine appropriate levels of exploitation. However, this approach to fishery management is predicated on the ability of fishery data collectors to correctly identify exploited spe- cies. Sharks and other elasmobranch fishes (Elasmobranchii) can be particularly difficult to identify in the field, due to the close physical similarity to other species and/or a lack of taxonomic resolution in some lineages. This paper provides an overview of the difficulties surrounding the field identifica- tion of a number of elasmobranch species found in the Arabian/Persian Gulf, where they are heavily exploited and in urgent need of careful management.
... The Arabian Seas Region (ASR), bordered by 20 nations, is regarded as a global hotspot for marine biodiversity (Stein et al., 2018) and provides habitat for ∼15% of all chondrichthyan species . While the ASR is prolific in fish resources, it is also one of the most over-exploited marine environments globally (Jabado and Spaet, 2017;Jabado et al., 2018). Several teleost species in the ASR have been over−exploited in the last two decades causing extreme threats to the teleost fisheries, with reported declines of 40-80% (FAO, 2007). ...
... Both targeted and incidental catches of elasmobranchs are being tapped to supply this demand (FAO, 2007;Henderson et al., 2016). The ASR is recognized for having the largest number of chondrichthyan fishers and traders in the world (Dent and Clarke, 2015;Dulvy et al., 2017;Jabado and Spaet, 2017). Within this region the top fishing nations are India, Iran, Pakistan, Oman, Yemen, Somalia, and Sri Lanka, respectively (Dent and Clarke, 2015;Jabado and Spaet, 2017). ...
... The ASR is recognized for having the largest number of chondrichthyan fishers and traders in the world (Dent and Clarke, 2015;Dulvy et al., 2017;Jabado and Spaet, 2017). Within this region the top fishing nations are India, Iran, Pakistan, Oman, Yemen, Somalia, and Sri Lanka, respectively (Dent and Clarke, 2015;Jabado and Spaet, 2017). Regional reported landings of chondrichthyans in 2015 represented 9.62% of global landings, despite seven countries in the region not reporting their chondrichthyan catches (FAO, 2017). ...
Article
Full-text available
Chondrichthyes, an ancient and diverse class of vertebrates, are crucial to the health of marine ecosystems. Excessive demand for chondrichthyan products has increased fishing pressure, threatening ∼30% of species with extinction in recent decades. India is the second-largest shark landing nation globally and the province of Gujarat, is the largest contributor to its shark exports. Despite their significant contribution to global fish supplies, chondrichthyan fisheries in Gujarat remain understudied and many species, data deficient, posing challenges to the conservation of remaining populations in the region. Here, we report results from taxonomic assessment of elasmobranchs at four key landing sites in Gujarat. We identified thirty-one species of sharks and rays with a significant bias toward capture of females and juveniles by fisheries. Our data indicate the presence of nursery areas for species such as Sphyrna lewini and Rhynchobatus laevis in the neritic areas off Gujarat. Further, we discovered extensions of the current distribution range for three species -Torpedo sinuspersici, Carcharhinus sorrah, and Rhinobatos punctifer. Taxonomic identities for a subset of species were confirmed using genomic analyses conducted with portable DNA sequencing tools. We present assessments for six data deficient species in the region – Rhinobatos annandalei, Rhinoptera jayakari, Maculabatis bineeshi, Pateobatis bleekeri, T. sinuspersici, and Carcharhinus amboinensis. Our investigation underscores species with urgent conservation needs and reduces data deficiencies. These data will inform and pivot future scientific and conservation efforts to protect remaining populations of some of the most vulnerable Chondrichthyes in the Arabian Seas Region.
... Thus, these species are a component of a much-complicated socio-economic complex (Moore, 2017). Exploited throughout their range (Kyne et al., 2020) for the high market value of 'white' fins in the Asian shark fin trade (Moore, 2017;Dulvy et al., 2016), the fin trade is therefore prevalent throughout the rhino ray population range (Chen, 1996;Diop and Dossa, 2011;Jabado et al., 2017;Belhabib et al., 2012;Cooke, 1997;Bruckner et al., 2011;Jabado et al., 2017Jabado et al., , 2017Zynudheen et al., 2004). The rising demand for rhino ray products (especially meat and fins) suggest that more specimens will continue to be landed and traded throughout the region if management is not in place. ...
... Thus, these species are a component of a much-complicated socio-economic complex (Moore, 2017). Exploited throughout their range (Kyne et al., 2020) for the high market value of 'white' fins in the Asian shark fin trade (Moore, 2017;Dulvy et al., 2016), the fin trade is therefore prevalent throughout the rhino ray population range (Chen, 1996;Diop and Dossa, 2011;Jabado et al., 2017;Belhabib et al., 2012;Cooke, 1997;Bruckner et al., 2011;Jabado et al., 2017Jabado et al., , 2017Zynudheen et al., 2004). The rising demand for rhino ray products (especially meat and fins) suggest that more specimens will continue to be landed and traded throughout the region if management is not in place. ...
... Thus, these species are a component of a much-complicated socio-economic complex (Moore, 2017). Exploited throughout their range (Kyne et al., 2020) for the high market value of 'white' fins in the Asian shark fin trade (Moore, 2017;Dulvy et al., 2016), the fin trade is therefore prevalent throughout the rhino ray population range (Chen, 1996;Diop and Dossa, 2011;Jabado et al., 2017;Belhabib et al., 2012;Cooke, 1997;Bruckner et al., 2011;Jabado et al., 2017Jabado et al., , 2017Zynudheen et al., 2004). The rising demand for rhino ray products (especially meat and fins) suggest that more specimens will continue to be landed and traded throughout the region if management is not in place. ...
Article
Rhinopristioid rays are among the most globally threatened cartilaginous fishes, almost all of which are Critically Endangered. Fishery pressure and lack of knowledge, especially where these elasmobranch fish overlap their habitats off developing countries in the Indo-West Pacific, impede their biological conservation which in turns result in unnoticed population depletion. Rhino rays are an important component of the Bangladeshi artisanal fishery; however, an understanding of these fisheries and their trade is limited. Fishers and traders were interviewed between June 2018 and June 2019 in four areas of southeast Bangladesh to characterize rhino ray fishing, trade and fishers' perception of population trends. All interviewed fishers reported lifelong rhino ray catch in sizable numbers and noted a steep decline in the catch over time, especially for Rhynchobatus spp. Seven species were documented-not only targeted by un-baited longlines but also by-caught in gillnets and set-bag nets. Unregulated and undocumented catch fuelled by substantial international trade to Myanmar on high-quality skin, meat and fins; and national usages of meat, liver, cartilages and intestines. Between 9000 and 33000 kg (avg. 23000 kg) of rhino rays were bought annually by each trader during 2015-2018. Southcentral shallow-water char (sand island) areas are perceived as essential habitats, hence providing important fishing grounds. The predominant threats are overexploitation by unselective gear use, bottom trawling, target catch, international trade and source of protein and income. Compliance with international trade control treaties or the Bangladeshi law was low, with most fishers (78%) unaware of specific regulation regarding rhino rays. It is crucial to adopt precautionary principles to prevent further rhino ray population declines. We propose a combination of actions rooted in sustainability and inclusiveness in this regard; e.g. a) trade mitigation, monitoring and enforcement, b) need for sustainable fisheries management regimes, c) need for habitat protection; finally, d) the importance of fishers' inclusiveness in conservation decision making.
... 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). ...
... Chondrichthyan catches from the "Gulf," Red Sea and particularly Pakistan declined from 2003 to 2011, while those from Oman have risen over this period (Davidson, Krawchuk, & Dulvy, 2015;FAO, 2017). Despite seven countries in the region not reporting their chondrichthyan catches, these landings represent 9.62% of global reported chondrichthyan landings (753,761 t in 2015) with the top shark fishing nations including India, Iran, Pakistan, Oman, Yemen, Somalia and Sri Lanka (Dent & Clarke, 2015;Glaser, Roberts, Mazurek, Hurlburt, & Kane-Hartne, 2015;Herath & Maldeniya, 2013;Jabado & Spaet, 2017). ...
... Although sometimes targeted, chondrichthyan catches in the Arabian Sea and adjacent waters are predominantly the result of incidental capture in fisheries targeting other, more valuable, demersal or pelagic species such as shrimp or tuna (Jabado & Spaet, 2017). Historic fishery landings have been poorly documented in this region, and therefore, the status of most individual exploited chondrichthyan stocks is unknown (e.g. ...
Article
Full-text available
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.
... In this region, coastal nations and communities are heavily dependent on marine resources, which include important shark and ray fisheries. Across the Arabian Sea and adjacent waters region, shark and ray landings from industrial and artisanal fishing support up to one fifth of the world's chondrichthyan fisheries 26 . Similarly, across the Southwest Indian Ocean, approximately 60 million people benefit from and contribute to an annual "gross marine product" (equivalent to a country's annual gross domestic product) of at least US$20.8 billion, where sharks are a high-value commodity 27 . ...
... The copyright holder for this preprint this version posted March 9, 2021. ; https://doi.org/10.1101/2021.03.08.434293 doi: bioRxiv preprint dependence on marine resources for livelihoods and economic contribution 26,27,32 , however, we stress that other fisheries management activities are equally important to implement in the region. Moreover, there is evidence that sustainable take of shark or ray species can be the most appropriate management response, as complete bans or prohibition of trade (of meat, fins, or other body parts) have not typically been sufficient to reduce fishing pressure on sharks and rays 21, 49,50 . ...
Preprint
Full-text available
Sharks and rays are possibly the most threatened Class of marine fishes and their declines can be halted if protected areas are optimised to benefit these species. We identify spatial priorities for all 63 endemic sharks and rays in the marine biodiversity hotspot, the Western Indian Ocean (WIO). Collectively, while the WIO nations currently surpass the 10% Aichi ocean protection target, this amounts to a dismal protection of only 1.57% of each species’ distribution range. We show that the entire ranges of all endemics can be achieved by protecting 11% of EEZs of WIO nations, well within reach of the new 30% of oceans by 2030 target. Regional management bodies exist, which if taken advantage of to implement shark and ray management, provide opportunities to implement more efficient management across the region. We recommend key management actions to implement and explicit incentivisation of international cooperation in the post-2020 biodiversity framework. Science for Society The past decade has seen massive growth in the establishment of marine protected areas (MPAs), driven by the Aichi biodiversity target of protecting 10% of all ocean areas. This expansion of MPAs, however, has largely occurred in areas residual to extractive uses, often coinciding with less threatened areas of lower conservation value. This coming decade will see a further push to ensure 30% of the oceans are protected by 2030. It is important to understand how existing and future MPAs should be placed to benefit threatened biodiversity. Currently this is unclear for sharks and rays, comprising a species group that is the most evolutionarily distinct vertebrate radiation in the world and also one of the most threatened. We identify both regional and national conservation priorities for expanding marine protected areas to benefit all 63 endemic sharks and rays occurring in the Western Indian Ocean region. We find that the region has already exceeded the 10% ocean protection target, but this amounts to an average of only 1.57% protection of the distribution ranges of these species. We show that protecting the top 10% priority sites will conserve almost half of the geographic range of each species yet require only 1.16% of the total EEZ – a tiny fraction of the 30% by 2030 target. We also show that regional collaboration among all nations can result in more spatially efficient conservation priorities. We recommend that the post-2020 biodiversity framework needs to explicitly incentivise regional cooperation between nations to efficiently achieve urgent targets and maximise benefits to biodiversity.
... There has been a surge on the studies focused on fisheries of elasmobranch including sharks in the Arabian Sea and contiguous sea (Chen, 1996;Dent and Clarke, 2015;Dulvy et al., 2014;Haque et al., 2018;Henderson et al., 2004;Jabado et al., , 2018Karnard et al., 2020). Some of these studies specifically dealt with fisheries (Jabado and Spaet, 2017). Some aspects of the fisheries of these species in Pakistan were also included in studies carried out by Jabado and Spaet (2017) and . ...
... Some of these studies specifically dealt with fisheries (Jabado and Spaet, 2017). Some aspects of the fisheries of these species in Pakistan were also included in studies carried out by Jabado and Spaet (2017) and . They have given detailed description of shark fisheries of the Arabian Sea including Pakistan. ...
Article
Full-text available
Sharks are important component of the coastal and offshore fisheries of Pakistan. A total of 79 species of sharks belonging to Infraclass Selachii (Subclass: Elasmobranchii) and 6 orders are recorded from Pakistan. Order Carcharhiniformeswas observed to be most prolific taxon represented by 48 species belonging to 6 families. Commercially important genus Carcharhinus is represented 18 species whereas genus Chiloscyllium by 5 species, genus Sphyrna by 4 species and genus Alopias by 3 species whereas other genera are represented by either 2 or 1 species. Three species namely Pondicherry shark (Carcharhinus hemiodon), Ganges shark (Glyphis gangeticus) and Indian sand tiger (Carcharias tricuspidatus) used to commonly occurring in Pakistan but now seem to be locally extinct as no confirmed record of their occurrence is available far the last about 40 years. The paper reviewed the historical records of shark species occurring in Pakistan resolving some of the issues in their taxonomy.
... These regions have also experienced widespread collapse in elasmobranch abundance , principally due to intensive fishing ( Jabado et al., 2018) stimulated during recent decades by the far-eastern demand for shark fin (Davidson et al., 2015). Countries in the Western Indian Ocean and Arabian Gulf regions that developed significant shark fishing industries during that period include Iran (Gerami and Dastbaz, 2013;Nergi, 2014;Jabado and Spaet, 2017), Oman, Kuwait, Qatar and United Arab Emirates (Henderson et al. 2007(Henderson et al. , 2008; Moore et al., 2012), Yemen (Shaher, 2007;Jabado and Spaet, 2017) and India (Akhilesh et al., 2011;Varghese et al., 2017). ...
... These regions have also experienced widespread collapse in elasmobranch abundance , principally due to intensive fishing ( Jabado et al., 2018) stimulated during recent decades by the far-eastern demand for shark fin (Davidson et al., 2015). Countries in the Western Indian Ocean and Arabian Gulf regions that developed significant shark fishing industries during that period include Iran (Gerami and Dastbaz, 2013;Nergi, 2014;Jabado and Spaet, 2017), Oman, Kuwait, Qatar and United Arab Emirates (Henderson et al. 2007(Henderson et al. , 2008; Moore et al., 2012), Yemen (Shaher, 2007;Jabado and Spaet, 2017) and India (Akhilesh et al., 2011;Varghese et al., 2017). ...
Article
Full-text available
Pakistan was listed as eighth globally in its landings of sharks and other elasmobranchs during the 1990s. Balochistan occupies over three-quarters of the coast of Pakistan yet the nature of the elasmobranch fshery there remains undocumented. Landings of elasmobranchs at landing sites were surveyed; the main species recorded were blacktip shark (Carcharhinus limbatus), bull shark (C. leucas) and spot-tail shark (C. sorrah). Altogether 25 shark species were identifed, of which nine are regionally vulnerable, eight endangered, and one (the sand tiger shark, Carcharias taurus) critically endangered. Of the thirteen other elasmobranchs recorded, fve are regionally vulnerable, two are endangered and one (the sawfsh, Pristis pristis) critically endangered. Local fshers and processors were interviewed about their industry. Sharks were caught using both long-lines and nets, largely in May – July. The fshers retained some meat (for consumption) or liver (for the oil used for waterproofng boats), but did not process the sharks themselves, instead selling them to agents of companies that exported fns and other elasmobranch products. Results showed that recorded landings in both Balochistan and the neighbouring Sindh Province have declined to a tenth or less of peak catch. Meanwhile, the numbers of registered fshermen continued to increase, a persistent threat to elasmobranchs stocks. It is recommended that a realistic national plan of action and widespread public awareness programme, with support to fshers and processors would help to alleviate this critical situation. Keywords: economic value, elasmobranch overfshing, fshers, fsheries, population decline, processors
... The sustainability of marine fisheries became a global concern because of the rapid increase in fishing pressure and arbitrarily exploitation, which may cause negative consequences for the ecosystems and societies [1]. This situation is worse, particularly in developing countries where proper management tools and political will lack and pervasive illegal fishing of juvenile and brood fishes is the fisheries' governing features [2][3][4]. This worst-case scenario of the stocks provides the impetus for articulating effective management tools, focusing on all concerned stakeholders' participation to promote conservation of the ecosystems and achieve the optimum yields to sustain the livelihoods and sustainable food supply [4,5]. ...
... This situation is worse, particularly in developing countries where proper management tools and political will lack and pervasive illegal fishing of juvenile and brood fishes is the fisheries' governing features [2][3][4]. This worst-case scenario of the stocks provides the impetus for articulating effective management tools, focusing on all concerned stakeholders' participation to promote conservation of the ecosystems and achieve the optimum yields to sustain the livelihoods and sustainable food supply [4,5]. Again, an effective management plan encompasses various management tools, including effort control, minimum mesh size regulations for nets, and maximum allowable catch limits [6,7]. ...
Article
Full-text available
The anadromous tropical Hilsa shad formed the largest single-species fishery in Bangladesh, making the highest contribution to the country’s total fish production (14%) and nearly 83% of the global Hilsa catch in 2018. However, increased fishing pressure made the fishery vulnerable, and hence, information on the stock condition and its response to the current degree of removal is essential to explore the future potential for sustainable exploitation. This study carried out a rigorous assessment based on three different methodological approaches (traditional length-frequency based stock assessment method for fishing mortality and exploitation, Froese’s length-based indicators for fishing sustainability, and a surplus production-based Monte Carlo method-CMSY, for fisheries reference points estimation) for the best possible estimates of the Hilsa stock status in the water of Bangladesh. The present findings revealed that the stock is likely to be overfished due to over-exploitation. Depending on the outputs, this study recommended a lower length limit for the catch (> 33 cm), distinguished a selectivity pattern (mesh size limit ≥ 8 cm), and proposed a yearly landing limit (within the range of 263,000–315,000 tons) for the sustainable management of the Hilsa fishery in Bangladesh. Keywords: Hilsa fishery; stock assessment; three different methodological approaches; over-exploitation and depleted stock biomass; management recommendations
... At present, the world is concerned about the sustainability of marine fisheries due to the rapid increase in fishing pressure and arbitrary exploitation, causing negative consequences for ecosystems and societies as well [6]. This case is getting worse, particularly within developing countries where proper management tools, in addition to political will, are lacking and pervasive illegal fishing of juvenile and brood fishes is the governing features of the fisheries [7][8][9]. This worst-case scenario of the stocks provides the impetus for the articulation of useful management tools that specialize in the participation of all concerned stakeholders to achieve the conservation of ecosystems and optimum yields to sustain livelihoods and sustainable food supply [9,10]. ...
... This case is getting worse, particularly within developing countries where proper management tools, in addition to political will, are lacking and pervasive illegal fishing of juvenile and brood fishes is the governing features of the fisheries [7][8][9]. This worst-case scenario of the stocks provides the impetus for the articulation of useful management tools that specialize in the participation of all concerned stakeholders to achieve the conservation of ecosystems and optimum yields to sustain livelihoods and sustainable food supply [9,10]. Further, an efficient management plan encompasses management tools, including efforts control, minimum mesh size regulations for nets, and the setting of maximum allowable catch limits [11,12]. ...
Article
Full-text available
Assessment of fish stock status is generally required for fisheries management, which is difficult when the data are limited. The length-based Bayesian Biomass (LBB) approach is a powerful and new method, where only the length-frequency data are used for estimating the status of fisheries resources. Here, we applied the LBB method to assess the status of seven commercially valuable marine fishes from the northern tip of the Bay of Bengal (BoB), Bangladesh. These species were Lepturacanthus savala, Pampus argenteus, Nemipterus japonicas, Nemipterus randalli, Ilisha filigera, Saurida tumbil, and Upeneus sulphurous. The current relative biomass (B/B0) ratios were smaller than the BMSY/B0 in five stocks, except for N. japonicas and N. randalli, and this indicates that, of the seven populations assessed, two are grossly overfished, three are overfished, and two are healthy stocks. Moreover, the length at first capture (Lc) was lower than the optimal length at first capture (Lc_opt) in all seven populations, which indicates growth overfishing, suggesting that increasing the mesh sizes would be beneficial. The present findings confirm that Bangladesh’s coastal water fishery resources are declining. More specific targeted management measures should be taken to recover the country’s marine fishery resources.
... Considering that scalloped hammerhead shark is globally listed as 'Critically Endangered' and that findings from this study point towards potential human health risks, consumption of this species should be avoided. In countries bordering the Gulf of Aden, shark meat is either directly consumed by fishermen or commercially traded (Jabado and Spaet, 2017), and fresh sharks are marketed across the region at various fish markets including Djibouti, Somalia and Yemen (Bonfil, 2003;Jabado and Spaet, 2017). As previously showed by Boldrocchi et al. (2019), consumption of certain shark species caught in this area suggests some level of concern from the daily exposure to certain TEs, but also to other persistent organic pollutants. ...
... Considering that scalloped hammerhead shark is globally listed as 'Critically Endangered' and that findings from this study point towards potential human health risks, consumption of this species should be avoided. In countries bordering the Gulf of Aden, shark meat is either directly consumed by fishermen or commercially traded (Jabado and Spaet, 2017), and fresh sharks are marketed across the region at various fish markets including Djibouti, Somalia and Yemen (Bonfil, 2003;Jabado and Spaet, 2017). As previously showed by Boldrocchi et al. (2019), consumption of certain shark species caught in this area suggests some level of concern from the daily exposure to certain TEs, but also to other persistent organic pollutants. ...
Article
We provided the first multi-species study investigating the presence and organotropism of trace elements in three tissues of 12 elasmobranch species. Shark species showed comparable TE loads, although milk sharks and juvenile scalloped hammerhead sharks exhibited the highest Cd and Hg levels, respectively. Fins accumulated higher levels of Pb, Co, and Cr; muscles higher V, As, and Hg; livers higher Se and Cd levels. The organotropism of TEs calls for cautious when choosing a tissue to be sampled since certain tissues, like fin clips, do not provide reliable surrogate for the internal loads of some TEs. Strong correlations between essential and toxic TEs indicated detoxification mechanisms, while the TMF provided evidence for Hg, As and Se biomagnification along the food-web. Considering the difficulties in assessing elasmobranchs contamination from different areas, the proposed multi-species approach represents a valuable way to estimate the species-specific accumulation and transfer of pollutants in sharks.
... In Saudi Arabian Red Sea waters, sharks have been heavily exploited from as early as the 1970s (Bonfil 2003). Small-scale artisanal fishers use handlines, gillnets, and traps to target top predators on and around coral reefs (Sanders and GR 1989;Spaet and Berumen 2015;Jabado and Spaet 2017). These types of artisanal fisheries are a direct threat to smaller coastal species in addition to the larger shark species that use these areas as breeding and nursery areas (e.g., Jennings et al., 2008). ...
... Unsurprisingly, there were no batoids found in the fish market surveys. This is most likely due to their low economic value, and those that are caught as bycatch are likely released (Spaet and Berumen 2015;Jabado and Spaet 2017). However, UAV surveys did not observe any of the shark species reported in the fish market, and BRUV surveys observed two shark species (one individual of each species). ...
Thesis
Years of unregulated fishing activity have resulted in low abundances of elasmobranch species in the Saudi Arabian Red Sea. Coastal populations of sharks and rays in the region remain largely understudied and may be at risk from large-scale coastal development projects. Here we aim to address this pressing need for information by using fish market, unmanned aerial vehicle and baited remote underwater video surveys to quantify the abundance and diversity of sharks and rays in coastal habitats in the Saudi Arabian central Red Sea. Our analysis showed that the majority of observed individuals were batoids, specifically blue-spotted ribbontail stingrays (Taeniura lymma) and reticulate whiprays (Himantura sp.). Aerial surveys observed a catch per unit effort two orders of magnitude greater than underwater video surveys, yet did not detect any shark species. In contrast, baited camera surveys observed both lemon sharks (Negaprion acutidens) and tawny nurse sharks (Nebrius ferrugineus), but in very low quantities (one individual of each species). The combination of survey techniques revealed a higher diversity of elasmobranch presence than using either method alone, however many species of elasmobranch known to exist in the Red Sea were not detected. Our results suggest that aerial surveys are a more accurate tool for elasmobranch abundance estimates in low densities over mangrove-associated habitats. The importance of inshore habitats, particularly for batoids, calls for a deeper understanding of habitat use in order to protect these environments in the face of unregulated fishing, mangrove removal, and anticipated developments along the coastline of the Saudi Arabian Red Sea.
... These regions have also experienced widespread collapse in elasmobranch abundance , principally due to intensive fishing ( Jabado et al., 2018) stimulated during recent decades by the far-eastern demand for shark fin (Davidson et al., 2015). Countries in the Western Indian Ocean and Arabian Gulf regions that developed significant shark fishing industries during that period include Iran (Gerami and Dastbaz, 2013;Nergi, 2014;Jabado and Spaet, 2017), Oman, Kuwait, Qatar and United Arab Emirates (Henderson et al. 2007(Henderson et al. , 2008; Moore et al., 2012), Yemen (Shaher, 2007;Jabado and Spaet, 2017) and India (Akhilesh et al., 2011;Varghese et al., 2017). ...
... These regions have also experienced widespread collapse in elasmobranch abundance , principally due to intensive fishing ( Jabado et al., 2018) stimulated during recent decades by the far-eastern demand for shark fin (Davidson et al., 2015). Countries in the Western Indian Ocean and Arabian Gulf regions that developed significant shark fishing industries during that period include Iran (Gerami and Dastbaz, 2013;Nergi, 2014;Jabado and Spaet, 2017), Oman, Kuwait, Qatar and United Arab Emirates (Henderson et al. 2007(Henderson et al. , 2008; Moore et al., 2012), Yemen (Shaher, 2007;Jabado and Spaet, 2017) and India (Akhilesh et al., 2011;Varghese et al., 2017). ...
Article
Full-text available
A first account of elasmobranch from Pakistan
... There has been a surge on the studies focused on fisheries of elasmobranch in the Arabian Sea and contiguous sea (Chen, 1996;Dent and Clarke, 2015;Dulvy et al.,2014;Haque et al., 2018;Henderson et al., 2004;2016;Jabado and Spaet, 2017;Jabado et al., 2014Jabado et al., , 2015Jabado et al., , 2018Karnard et al., 2020). Jabado and Spaet (2017) have given a detailed description of shark fisheries including stingrays of the Arabian Sea including Pakistan. ...
... There has been a surge on the studies focused on fisheries of elasmobranch in the Arabian Sea and contiguous sea (Chen, 1996;Dent and Clarke, 2015;Dulvy et al.,2014;Haque et al., 2018;Henderson et al., 2004;2016;Jabado and Spaet, 2017;Jabado et al., 2014Jabado et al., , 2015Jabado et al., , 2018Karnard et al., 2020). Jabado and Spaet (2017) have given a detailed description of shark fisheries including stingrays of the Arabian Sea including Pakistan. Studies on the fisheries of these species in Pakistan were also included in . ...
Article
Full-text available
Stingrays belonging to Family Dasyatidae are commercially exploited in Pakistan (Northern Arabian Sea) since long and mainly landed as bycatch of trawling and bottom-set gillnet fishing, In some areas along Sindh and Balochistan coast target stingrays fisheries based on fixed gillnet used to main source of their landings. It is estimated that their commercial landings ranged between 42,000 m. tons in 1979 to 7,737 metric tons in 2019. Analysis of the landing data from Karachi Fish Harbor (the largest fish landing center in Pakistan) revealed that 27 species of stingrays belonging to 14 genera are regularly landed (January 2019-December 2019). Smooth coloured stingrays (Himantura randalli/M. arabica/M.bineeshi) contributed about 66.94 % in total annual landings of stingrays followed by cowtail and broadtail stingrays (Pastinachus sephen and P. ater) which contributed 24.42 %. Spotted/ocellated/reticulated stingrays (Himantura leoparda, H. tutul, H. uarnak and H. undulata) contributed and 5.71 % in total annual landings of stingrays. Scaly whipray (Brevitrygon walga) and aharpnose stingray (Maculabatis gerrardi) contributed about 1.95 % and 0.98 % in total annual stingray landings of stingrays respectively. Three species leopard whipray (Hiamntura undulata), round whipray (Maculabatis pastinacoides) and Indian sharpnose stingray (Telatrygon crozieri) are reported for the first time from Pakistan coast. There is an important aimed fisheries for stingrays based in some coastal villages along Balochistan coast where fixed bottom set gillnet placed in shallow waters (15-20 m.), however, these fishes are also caught as by-catch of gillnetting and shrimp trawling. The paper discusses about commercial landings and conservation aspects of stingrays in Pakistan. It urges for enactment of national and provincial legislation for protection of stingrays as well as for placing some of the species which are either critically endangered, vulnerable or near threatened to be placed CITES appendices. It also urges for evaluation of a large number stingrays which have not been assessed for their IUCN Red List listings.
... Despite the UAE having developed legislation to regulate shark fishing (including species-specific protections), most species (especially sharks) are still landed as bycatch due to an overlap between the seasonal shark fishing ban and open gillnet fishing season 22 . Unsustainable fishing and overexploitation of elasmobranch resources, coupled with weak enforcement of fishing policies, are widespread in the region and these low CPUE numbers are likely a reflection of stocks that have been depleted from over two decades of overfishing 21,23 . ...
Article
Full-text available
Data on the diversity and relative abundance of elasmobranchs (sharks and rays) in the Arabian Gulf have been limited to fishery-dependent monitoring of landing sites. Understanding the diversity and abundance of sharks and rays is, however, crucial to inform policy and management plans. Baited Remote Underwater Video Surveys (BRUVS) were conducted in 2015–2016 across the United Arab Emirates Arabian Gulf waters encompassing a range of depths and habitat types. Data from 278 BRUVS (757 hours soak time) were analysed to gather information on diversity, relative abundance, species distribution, and habitat associations. Surveys recorded 213 individuals from 20 species of sharks and rays at 129 stations. The frequency of occurrence of species usually discarded by fishers such as the Arabian carpetshark (Chiloscyllium arabicum) and stingrays (Himantura spp.) was high, accounting for 60.5% of observed elasmobranchs. Despite the large survey area covered and extensive sampling effort, the relative abundance of sharks and rays was low at 0.28 elasmobranchs per hour, 0.13 sharks per hour, and 0.15 rays per hour. This CPUE was reduced to one of lowest recorded abundance on BRUVS from around the world when removing the two discarded species from the analysis (0.11 elasmobranchs per hour). These results likely reflect the intense fishing pressure and habitat loss contributing to population declines of many elasmobranchs in the Arabian Gulf. Findings provide a baseline for future work and can support the design of conservation strategies for sharks and rays in the UAE.
... Our rapid on-site detection assays have shown good specificity and can be used for on-site law enforcement of all CITES-listed shark species which are commonly found in the fin market 3,12 . It will be useful for screening of processed shark fin products which is difficult to be identified using morphological identification guide and shark products such as shark meat as they are hardly identified based on morphology 22,45 . The result has also shown that COI and NADH2 regions are suitable for species-level identification, especially for species with a high nucleotide similarity with congeneric species. ...
Article
Full-text available
Shark fin is a delicacy in many Asian countries. Overexploitation of sharks for shark fin trading has led to a drastic reduction in shark population. To monitor international trade of shark fin products and protect the endangered species from further population decline, we present rapid, user-friendly and sensitive diagnostic loop-mediated isothermal amplification (LAMP) and effective polymerase chain reaction (PCR) assays for all twelve CITES-listed shark species. Species-specific LAMP and PCR primers were designed based on cytochrome oxidase I (COI) and NADH2 regions. Our LAMP and PCR assays have been tested on 291 samples from 93 shark and related species. Target shark species could be differentiated from non-target species within three hours from DNA extraction to LAMP assay. The LAMP assay reported here is a simple and robust solution for on-site detection of CITES-listed shark species with shark fin products.
... Both I. omanensis and R. oligolinx are species that show a significant intergender size difference, where females are much larger than the males (Henderson et al., 2009;Moore et al., 2012). The differences in sizes across the coasts of India and in regions around the Gulf could be related to the prey they consume, or could result from the type of gear used: for example, trawlers do not operate in fisheries off Oman and the United Arab Emirates (Jabado & Spaet, 2017). ...
Article
• Biological data including size, sex ratios, male maturity, and length and weight relationships for four commercially important shark species, including the milk shark (Rhizoprionodon acutus Rüppell, 1837), the grey sharpnose shark (Rhizoprionodon oligolinx Springer, 1964), the spadenose shark (Scoliodon laticaudus Muller & Henle, 1838), and the bigeye smoothhound shark (Iago omanensis Norman, 1939), landed in Porbandar, Gujarat, India, are provided. • All four species were landed by trawlers and gill‐netters across three defined seasons, with seasonal differences. Higher proportions of mature R. acutus and S. laticaudus were observed in the pre‐monsoon season, with neonates caught throughout the year, whereas higher proportions of mature R. oligolinx and I. omanensis were recorded during the monsoon season, with neonates caught in post‐monsoon and pre‐monsoon, respectively, showing important species‐level differences. • These small‐bodied shark species (less than 1 m in total length) showed positive allometry in their length and weight relationships. Unlike the other three species, I. omanensis showed high disparity in total lengths (LT) between the sexes, with females being larger than males, and with males maturing faster, with the smallest mature male of 33.58 cm LT. Females outnumbered males except in R. acutus, and pregnant females of all species were recorded at least once. Of the 971 males recorded across species, 55.1% were mature and 44.9% were immature. • Results from this study indicate that there is substantial overlap between the distributions of these species and fishing activities, and show that most, if not all, life stages are susceptible to mortality as a result of fishing. • This study provides managers with a better understanding of the life‐history traits of these commercially important species to support future quantitative population assessments, and provides a baseline of trends in fishing‐related mortality.
... However, distinct habitat clusters result in a high species turnover, or ß-diversity, within the Gulf, and comparisons with the nearby Red Sea reveal that the Gulf has a dissimilar species assemblage, making it of special conservation concern (Price 2002, Sheppard et al. 2010, Ludt et al. 2018. High primary productivity in the Gulf supports large fisheries for shrimps, lobsters, a wide variety of bony fishes, and elasmobranchs (Carpenter et al. 1997, Jabado & Spaet 2017), yet rapid development and regulatory differences between the eight countries bordering the Gulf have resulted in the overexploitation of many of these marine resources (Price 1993, Sale et al. 2011, Buchanan et al. 2019. Threats to the entire Gulf include factors such as population growth, increased oil exploration and shipping traffic, overexploited fisheries, and global climate change, making the need for categorizing the biodiversity of this region essential (Sale 2011, Sheppard et al. 2010. ...
Article
Full-text available
The Arabian Gulf is a semi-enclosed sea largely isolated from surrounding bodies of water. Due to several physical attributes, this basin comprises a variety of habitats that are influenced by strong seasonal fluctuations in abiotic conditions, which in turn puts considerable stress on local species. The biodiversity of this body of water has been historically understudied and is under increasing threats from overexploitation, development, and climate change. Documenting the current state of this biodiversity is therefore of paramount importance. The coastal waters of the United Arab Emirates make up the majority of the southern portion of the Gulf, and the species richness of these waters has never been formally documented. Here, we present the findings of an inshore and offshore biodiversity survey that recently sampled along the entirety of the southern coast of the Gulf. We focused on the non-elasmobranch ichthyological biodiversity (i.e. bony fishes), and established a regional collection housed at the Environmental Agency-Abu Dhabi (EAD) for future researchers to use and to reference. Additionally, we mtDNA barcoded a subset of the specimens collected using the mitochondrial cytochrome oxidase subunit 1 (COI) marker. In total, 631 specimens were collected from 164 different localities representing 158 species and 60 families. We sequenced 465 of these individuals to assess the match to all sequences in the BOLD database and their species identification. The results suggest possible cryptic species or strong population structuring that warrant future taxonomic exploration. This study represents the largest bony-fish barcoding effort for the region to date and provides data that will be useful for scientists, non-governmental organizations, and policymakers moving forwards.
... The near absence of marine megafauna such as sharks indicates that these top predators were likely removed by fishing decades ago. Although traditional Bedouin fishing methods are unlikely to be suitable to catch large sharks, they were caught occasionally up to the 70s (Melamid 1957;Baranes and Ben-Tuvia 1978) and overfishing of sharks is well-reported in the wider Red Sea (Tesfamichael et al. 2014;Spaet et al. 2016;Jabado and Spaet 2017). Both herbivorous and piscivorous fish showed declining population trends indicating that fishing at current levels is unsustainable. ...
Thesis
Full-text available
Coral reef ecosystems around the world are declining as a result of human impacts including overfishing, pollution and climate change. The coral reefs of South Sinai are significant because of their unique biodiversity, the income that they generate for Egypt through diving tourism and their importance as traditional fishing grounds for the Mzeina Bedu. This PhD takes a multidisciplinary approach to evaluate the status of coral reefs in South Sinai, with particular emphasis on Bedouin fishers and their fisheries. In Chapter 1, I examine the importance of culture and traditional knowledge in the successful management of coral reefs and natural resources in general. In Chapter 2, I focus on the Bedouin tribes of South Sinai to understand their history and socioeconomic status; investigating their fishing techniques and sites as well as their traditional understanding of coral reef biodiversity and ecology. Chapter 3 focusses on the ecological status of finfish populations at sites along the South Sinai coastline, evaluating the status of stocks and potential Bedouin fishery impacts. Chapter 4 examines the invertebrate fishery, which is mainly practised by Bedouin women and targets Tridacna clams. Chapter 5 takes a fishery-dependent approach to assess the catch of Bedouin fishers, to understand important biological and socioeconomic parameters that influence the fishery. In Chapter 6, I use statistical modelling techniques on long-term coral reef ecosystem data sets from the study area to analyse longer-term trends in the ecological status of reefs in South Sinai and likely causes for these trends. Coral reefs provide income, tourism, food and coastal protection to local communities and indigenous people throughout the tropics. The socio-cultural facets of the Mzeina Bedu have been inextricably connected to the reefs and associated fisheries of South Sinai for generations. However, exploited finfish and invertebrate communities have declined in both size and abundance with increased fishing pressure, resulting in ecosystem-wide impacts. The Mzeina themselves should be integral to any proposed fisheries monitoring or management initiatives, and technological approaches may provide useful cost-effective tools. Fisheries ecosystem-level declines have been apparent over at least the last decade and sustained monitoring is essential to ensure that the impact of management initiatives may be measured. If urgent collaborative management and enforcement actions are implemented alongside a programme to develop livelihood opportunities for the Mzeina, the reefs of South Sinai could return to a state that supports both the socioeconomic needs of the Bedu and continues to generate substantial tourism income.
... Therefore, independent genetic monitoring approaches, such as the one described here, should be implemented in other large shark fin trade hubs (e.g., China, Thailand, Singapore, Vietnam) to detect changes in trade of fins over time and to assess compliance with CITES reporting requirements. In addition, faster, cheaper, and more portable DNA forensic tools must be developed to increase the capacity of CITES parties to monitor the trade in products, such as meat, that are not easily identified to species and address emerging tactics by illegal actors to conceal fins from listed species by altering their morphology (Jabado & Spaet, 2017). The recent positive momentum for shark trade management by CITES parties has the potential to trigger the promotion of intergovernmental cooperation, funding, and capacity-building to implement new techniques and protocols to ensure more effective implementation of CITES listings for sharks. ...
Article
Full-text available
Trade‐driven overexploitation threatens many sharks. Twelve of the world's most vulnerable shark species have been listed on the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to regulate internationally traded products such as meat and dried fins. CITES records indicate that Hong Kong was the world's top legal importer of dried fins from listed sharks in 2015 (N = 8 species at that time), but traded a relatively small volume, with a few partners, in a small number of shipments (16). In contrast two CITES Appendix II listed hammerheads were consistently the fourth and fifth most common species (out of >80) in processed fin trimmings (N = 9,200) collected randomly from the Hong Kong retail dried fin market from February 2014 to December 2016 and were found in 100% of sampling events and in 66% of sampled retail vendors. This difference, and the fact that exporting nations previously known to land these species were not among those to report trade to CITES, suggest that listed species were often imported without CITES documentation in 2015. There are a number of incentives for trade hubs to meet their obligations to this treaty, which they could achieve by scaling up monitoring capacity and increasing inspection efficiency.
... Historically, all research efforts on fishing productivity have focused on species of high commercial value (e.g., tunas) (FAO, 2012). It was only in the last two decades that the lack of monitoring of elasmobranch fishing has become alarming since its impacts are now measurable (Stevens et al., 2000;Jabado and Spaet, 2017;Wosnick et al., 2019;Giovos et al., 2020). Nowadays, there is a consensus on the ecological importance of elasmobranchs, with unrestrained capture being a matter of concern worldwide (Carlson et al., 2019). ...
Article
The use of animals from commercial fishing for scientific purposes is a reality in Brazil, emphasizing the importance of a good relationship between researchers and fishermen. To assess the effectiveness of traditional communities' inclusion in research, this study provides comparative data on elasmobranch landing patterns and on-board processing before and after participatory activities. Through the inclusion of members of the fishing community, a change in behavior and recognition of the importance of elasmobranch research and conservation were detected. Such a strategy is an effective empowerment tool, benefiting not only the management of coastal species but also valuing traditional knowledge in research and creating a work environment based on trust and commitment.
... Silky sharks (Carcharhinus falciformis) have been the second most common species in the shark fin trade through one of the world's largest fin trade centers, Hong Kong Special Administrative Region of the People's Republic of China (hereafter "Hong Kong"), for the last two decades (Cardeñosa, Fields, Babcock et al., 2018;Clarke et al., 2006;Fields et al., 2018). This remarkably consistent contribution reflects high landings of this species, most likely because they have been the most common shark taken incidentally in pelagic tuna fisheries in subtropical and tropical regions worldwide (Amorim, Arfelli, & Fagundes, 1998;Clarke et al., 2014;Gilman et al., 2008;Hutchinson, Itano, Muir, & Holland, 2015;Jabado & Spaet 2017;Simeon et al., 2018;Simpfendorfer, Hueter, Bergman, & Connett, 2002). This is concerning because this species is classified as vulnerable by the International Union for Conservation of Nature (IUCN; Rigby, Sherman, Chin, & Simpfendorfer, 2017) and ecological risk assessments indicate that silky sharks are among the pelagic shark species most vulnerable to overexploitation (Cortés et al., 2010). ...
Article
Full-text available
The silky shark is the second most common shark in Southeast Asia’s dried fin markets and is managed in the Atlantic Ocean by the International Commission for the Conservation of Atlantic Tuna (ICCAT) and by three Indo-Pacific regional fisheries management organizations (RMFOs). ICCAT reports ~ 7% of global silky landings but there is a moratorium on the export of their fins. During a four-year period (2014- 2017) we used genetic differentiation observed between Atlantic and Indo-Pacific silky sharks to assess the contribution of Atlantic individuals to fins randomly obtained in the two largest shark fin markets in the world, Hong Kong and Guangzhou, China (N=604). We did not detect any Atlantic fins in either market despite robust sampling effort with an estimated Indo-Pacific contribution of 99.8% to these markets. These findings indicate that supply chains for silky shark fins in Hong Kong and Guangzhou primarily originate in the Indo-Pacific and are mainly under the purview of three RFMOs. Our results are consistent with the possibility that ICCAT parties have achieved high compliance with the ban on silky sharks. We suggest research and monitoring improvements that could enhance our understanding of the global trade of silky sharks and enable better fisheries management.
... Both I. omanensis and R. oligolinx are species that show a significant intergender size difference, where females are much larger than the males (Henderson et al., 2009;Moore et al., 2012). The differences in sizes across the coasts of India and in regions around the Gulf could be related to the prey they consume, or could result from the type of gear used: for example, trawlers do not operate in fisheries off Oman and the United Arab Emirates (Jabado & Spaet, 2017). ...
Poster
A preliminary assessment of life history studies of four commercially important shark species landed at Porbandar, Gujarat,
... Land-born plastic waste may reach the ocean during rain runoffs and tidal washing (Ng et al., 2018). Moreover, marine boats have historically contributed significantly to marine pollution: more than 23,000 tons of plastic packaging material were disposed of by the global fishing fleet in 1970 (Jabado and Spaet, 2017). ...
Article
Full-text available
The nature of micro- and nanoplastics and their harmful consequences has drawn significant attention in recent years in the context of environmental protection. Therefore, this paper aims to provide an overview of the existing literature related to this evolving subject, focusing on the documented human health and marine environment impacts of micro- and nanoplastics and including a discussion of the economic challenges and strategies to mitigate this waste problem. The study highlights the micro- and nanoplastics distribution across various trophic levels of the food web, and in different organs in infected animals which is possible due to their reduced size and their lightweight, multi-coloured and abundant features. Consequently, micro- and nanoplastics pose significant risks to marine organisms and human health in the form of cytotoxicity, acute reactions, and undesirable immune responses. They affect several sectors including aquaculture, agriculture, fisheries, transportation, industrial sectors, power generation, tourism, and local authorities causing considerable economic losses. This can be minimised by identifying key sources of environmental plastic contamination and educating the public, thus reducing the transfer of micro- and nanoplastics into the environment. Furthermore, the exploitation of the potential of microorganisms, particularly those from marine origins that can degrade plastics, could offer an enhanced and environmentally sound approach to mitigate micro- and nanoplastics pollution.
... The DMNP hosts the largest known M. alfredi aggregation in the Red Sea [27,29] and is considered a globally important site for the species' conservation [30]. While individuals are incidentally captured in artisanal gill net fisheries in the vicinity [30] there does not appear to be a regionally active fishery for M. alfredi or other devil rays [31]. DMNP may serve as a key refuge or source population for M. alfredi in the Red Sea and the broader East African coastline, but the population dynamics and movement ecology of M. alfredi in this region remain understudied. ...
Article
Full-text available
Background: Reef manta ray (Mobula alfredi) populations along the Northeastern African coastline are poorly studied. Identifying critical habitats for this species is essential for future research and conservation efforts. Dungonab Bay and Mukkawar Island National Park (DMNP), a component of a UNESCO World Heritage Site in Sudan, hosts the largest known M. alfredi aggregation in the Red Sea. Methods: A total of 19 individuals were tagged using surgically implanted acoustic tags and tracked within DMNP on an array of 15 strategically placed acoustic receivers in addition to two offshore receivers. Two of these acoustically monitored M. alfredi were also equipped with satellite linked archival tags and one individual was fitted with a satellite transmitting tag. Together, these data are used to describe approximately two years of residency and seasonal shifts in habitat use. Results: Tagged individuals were detected within the array on 96% of monitored days and recorded an average residence index of 0.39 across all receivers. Detections were recorded throughout the year, though some individuals were absent from the receiver array for weeks or months at a time, and generalized additive mixed models showed a clear seasonal pattern in presence with the highest probabilities of detection occurring in boreal fall. The models indicated that M. alfredi presence was highly correlated with increasing chlorophyll-a levels and weakly correlated with the full moon. Modeled biological factors, including sex and wingspan, had no influence on animal presence. Despite the high residency suggested by acoustic telemetry, satellite tag data and offshore acoustic detections in Sanganeb Atoll and Suedi Pass recorded individuals moving up to 125 km from the Bay. However, all these individuals were subsequently detected in the Bay, suggesting a strong degree of site fidelity at this location. Conclusions: The current study adds to growing evidence that M. alfredi are highly resident and site-attached to coastal bays and lagoons but display seasonal shifts in habitat use that are likely driven by resource availability. This information can be used to assist in managing and supporting sustainable ecotourism within the DMNP, part of a recently designated UNESCO World Heritage Site.
... The ongoing changing aspects of these two processes cause ongoing difficulties for those with conservation interests. Studies revealed that the Arabian Seas Region plays an important role in the global landings of sharks and rays [27,28]. The authors state that observed landings varied among regions and across seasons, results clearly showed that shark landings were dominated by small-sized specimens, which is indicative of overexploitation. ...
Article
Full-text available
Challenges that relate to shark conservation may well be a combination of the intersection of people's livelihoods and the ineffectiveness of management strategies. Given the current protection initiatives as well as the implementation of tighter laws restricting hunting and trade, shark conservation is still recognized as a major environmental challenge. The United Arab Emirates (U.A.E.) is used as an export hub and is one of the primary exporters of shark fins to Hong Kong, with a large proportion of fins traded to be from species at high risk of global extinction. The present-day management of shark fisheries also shows shortcomings concerning lawfulness, specifically those relating to regulatory compliance, fishing techniques, and control of finning occurrences. These concerns are not unique to the U.A.E. but emphasize the fact that there are far-reaching problems related to shark conservation. Even in a milieu of strengthened conservation measures and revised legislature, existing information on the effectiveness of a shark finning ban may still be misleading when viewed in the light of over-exploitation and global species abundance. It is therefore important that proper management must be implemented at the inception of shark fisheries. For the U.A.E., this has not always been the case. Instead, the trend was one of limited control and lack of compliance, unfortunately, resulting in a rapid decline in shark abundance, to the point where sharks struggle to recover. This paper focuses on the importance of the species, reviews the current monitoring framework, and seeks to enhance shark protection.
... The consumption of elasmobranch meat is common in many tropical countries (Kyne et al., 2020;Spaet and Berumen, 2015;Jabado and Spaet, 2017;Moore, 2017), including Bangladesh (mostly by tribal communities). The most sought-after and most valuable species (i.e. ...
Article
Trade in elasmobranch products is a circum-global practice negatively impacting elasmobranch populations. Although Asia is at the centre of the shark fin trade, countries like Bangladesh, remain data-poor regarding trade dynamics. In the Bay of Bengal region, Bangladesh has a long-standing history of producing and trading products from vulnerable and protected elasmobranchs both nationally and internationally. A limited understanding of trade currently precludes Bangladesh from enforcing regulations effectively and taking timely conservation actions. To address this knowledge gap, we characterized elasmobranch trade by identifying stakeholders involved in national and international trade, routes used, trade hubs, and ports in Bangladesh. We found that most of the trade remains unreported and violates the Wildlife (Conservation and Security) Act, 2012 and CITES mandates. We identified the south-eastern region as a trade hub with a syndicate of traders annually exporting elasmobranch products predominantly to China via Myanmar. High-quality fins and dried meat drive international trade, including products from Critically Endangered sawfish (Pristidae), guitarfishes (Glaucostegidae, Rhinobatidae), wedgefishes (Rhinidae), hammerhead sharks (Sphyrnidae), and large requiem sharks (Carcharhinidae). Also prevalent is a substantial national demand for elasmobranchs for consumption and traditional medicinal uses. Apart from limited alternatives, a low efficiency of acquiring maximum profits in trading other fishery products, an inequality of profit sharing and limited awareness of laws amongst traders results in their non-compliance towards the Wildlife Act, 2012. Along with amendments to this national Act, it is essential to protect threatened species beyond just legal regimes. Enhanced monitoring and inclusive policies are essential for disincentivizing traders to trade such products.
... Despite the significant contribution, the sustainability of small-scale marine fisheries has become a challenge regardless of geographical settings due to habitat loss, rapid increases in fishing pressure, and arbitrarily exploitation, all of which may cause detrimental consequences for the ecosystems and societies (Mora et al., 2009). This situation is worse, particularly in developing countries, where adequate management tools and political will lack, and widespread illicit fishing of juvenile and brood fishes are the common characteristics of the fisheries (Froese, 2004;Spaet et al., 2012;Jabado and Spaet, 2017). Given this, the formulation of effective management plans that ensure relevant stakeholders' participation is urgent to promote ecosystem conservation and achieve optimal yields to sustain livelihoods and food supply (Jabado et al., 2015). ...
Article
The small-scale fisheries in the northern Bay of Bengal coast of Bangladesh have been suffering due to an uncontrolled expansion of the fishing effort. Given this, it is important for all stakeholders to understand the current stocks’ status and their response to the present degree of removal. This study used two different methodological approaches to assess six commercially important fish species’ stock status from this coast with fisheries representative length-frequency data: a length-based Bayesian biomass estimation method (LBB) for relative fishing mortality and stock biomass, and Froese’s length-based indicators (LBIs) for the sustainability of the fisheries. The present findings revealed that the biomass of Bregmaceros mcclellandi, Escualosa thoracata, Ilisha filigera, Johnius belangerii and Coilia dussumieri was below the target reference points (B/Bmsy < 1 in LBB and SB < SBtarget in LBIs), suggesting overfished status of those fisheries. The biomass of Megalaspis cordyla, on the other hand, was above the threshold level (B/Bmsy=1.1 in LBB & SB > 0.4SBtarget in LBIs). Depending on the outputs, this study recommended not to catch fish with lengths equal or smaller than the length at first sexual maturity to avoid growth overfishing, exclude the mega-spawners (length > Lopt+10%) from the catch for preventing recruitment overfishing, and bring the fishing mortality back to the sustainable level (F=M) by reducing the existing number of boats to its half for fisheries long-term survivability.
Book
Full-text available
The Atlas is the results of occuring of tuna and allied resources along the Indian EEZ for last 3 decades
Book
Full-text available
This report provides an overview of the con- servation status of chondrichthyans (sharks, rays, and chimaeras) in the Arabian Seas Region (ASR) and describes the results of a regional Red List workshop held in Abu Dhabi, United Arab Emirates, in February 2017. It identies those species that are threatened with extinction at the regional level, so that appropriate conservation action can be taken to improve their status. A regional overview of chondrichthyan fisheries, management and conservation is also presented. Although 184 species of sharks, rays, and chimaeras occur in the ASR, only the confirmed 153 species were considered in this project.The geographic scope encompasses the Red Sea, Gulf of Aden, Arabian Sea, Sea of Oman and the Gulf.This includes the Exclusive Economic Zone (EEZ) of 20 countries bordering three Large Marine Ecosystems (i.e., the Arabian Sea, Red Sea, and Somali Current). This region comprises some of the largest and most important chondrichthyan fishing nations in the world, including India and Pakistan. All assessments followed the IUCN Red List Categories and Criteria Version 3.1 and the Guidelines for Application of the IUCN Red List Criteria at Regional and National Levels Version 4.0. During the workshop, a network of leading international and regional experts on chondrichthyans and fisheries compiled data and knowledge to prepare 30 global (endemic species) and 123 regional species assessments. All assessments were agreed on by consensus at the workshop and any changes to statuses during the review process were agreed on through email correspondence with lead assessors and contributors prior to their submission to the IUCN Red List of Threatened Species and inclusion in this report.
Article
In spite of the ecological services provided by elasmobranchs, their diversity and populations are significantly declining even before appropriate assessments are conducted. This paper presents information on elasmobranch diversity in the Saudi waters of the Arabian Gulf based on fishery-independent and dependent surveys. A total of 369 individual sharks and batoids were collected from 119 out of 228 trawl stations surveyed between 2013 and 2016. Gymnura poecilura and Carcharhinus dussumieri were the most dominant batoid and shark species, respectively. The catch per unit area indicated the waters around Jana Island as a hotspot of elasmobranchs. A total of 135 surveys at the landing sites and fish markets from 2016 to 2020 showed that 88% of elasmobranchs (out of 4,055 individuals recorded) were caught by gill nets. Sharks were the most abundant (> 80 %) with three dominant species: Carcharhinus sorrah, C. humani, and C. limbatus. In total, 47 species of elasmobranchs (24 sharks and 23 batoids) belonging to 16 families and 5 orders were recorded from a possible 58 total species predicted by species richness extrapolators (Chao 1). High values of Margalef richness (> 2) and Shannon-Wiener index (3-4) suggested rich diversity of elasmobranchs in the study area with homogeneous distribution over the years and seasons as shown by cluster and similarity profile analysis. Of the 47 species recorded, six species were Critically Endangered regionally, six Endangered, and seven species Vulnerable according to the IUCN Red List of Threatened Species, necessitating proper management and conservation measures.
Article
The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) controls the wildlife trade. All the Gulf Cooperation Council (GCC) countries are parties to CITES. GCC countries are the prime destination of exported falcons and Oud. In 2016, Saudi Arabia and the UAE were the destinations of approximately 26.8% of the world’s seized specimens of agarwood. These facts justify examining countries’ arrangements for implementing and enforcing the convention. Researchers used the Institutional Analysis and Development (IAD) framework for inquiry. Sources of information included site visits, surveys, interviews, and documents. The researchers interviewed 742 interviewees representing different stakeholder groups. Results show that the present legal framework is not wholly conducive to an integrated and holistic measure for complying with the convention. Traditions and culture, lack of trained cadres, complicated procedures, inadequate coordination, lack of economic incentives, and imperfect information are challenges for effective implementations of the convention. The research confirms the importance of institutional setup, legal systems, and socioeconomic context in successfully complying with and enforcing CITES. Coordination between executing agencies, strict law enforcement, and capacity building contribute to the effective implementation of the convention.
Article
Scomberomorus commerson (here after ‘Kingfish’) is the choicest table fish of the Gulf Cooperation Council (GCC) region and the most valuable finfish of Oman. Catch-effort data from 2000 to 2019 of Oman’s Kingfish fishery was fit to Schaefer model (log-normal assumption) for estimating maximum sustainable yield (MSY) and biological reference points (BRPs). Carrying capacity (K), catchability coefficient (q), population growth rate (r) and MSY of Kingfish were 36,745 tonnes, 0.0000161, 0.382 and 3,507 tonnes, respectively. At present, fishing effort (ENOW) (i.e. number of boats) is 18,982, which is beyond the sustainable limit i.e. EMSY = 11,846 and if the number of boats reaches to 23,692 then Kingfish stock may collapse. All the BRPs are higher than their sustainable limits, which indicate Kingfish stock is overfished. Stock Reduction Analysis suggests that the stock was in the safe zone between 2005 and 2007, it was in the overfishing zone from 2008 to 2012 and 2013 onwards the stock is in the overfished zone. A complete ban on Kingfish fishing in Oman may allow the stock to rebuild to Biomass at Maximum Sustainable Yield in three years or limiting the annual catch at 1,500 tonnes/year till 2026 may yield the same result. A transboundary management of Kingfish fishery is suggested for the GCC region. Forming a joint scientific council for monitoring and facilitating data availability, similar ban periods, mesh size regulations and a ‘payment for ecosystem services’ scheme may lead Kingfish fishery of the GCC region towards sustainability.
Chapter
The evolutionary origins of sharks date back more than 400 million years, ranking them among the oldest extant taxa of vertebrates. Sharks are found throughout the world’s oceans, inhabiting coastal waters and open seas, from the surface to depths of 3000 m. Of the more than 500 shark species described to date, only 29 are found in the Red Sea. In this chapter, I summarise the available information on life-history, habitat use, population genetics, fisheries and conservation of sharks in the Red Sea. This information is supplemented with unpublished data on reproductive parameters and shark fisheries that I collected between 2010 and 2014 along the Saudi Arabian Red Sea coast. Overall, it is apparent that, relative to other ocean basins, information on shark biology is sparse for the Red Sea. Yet, the presented data is sufficient to clearly indicate strong overfishing of Red Sea shark populations, calling for urgent regional efforts to assess the status of these species and to develop and implement effective management plans to ensure socio-ecological sustainability.
Article
Full-text available
There is recent evidence of widespread declines of shovelnose ray populations (Order Rhinopristiformes) in heavily fished regions. These declines, which are likely driven by high demand for their fins in Asian markets, raises concern about their risk of over-exploitation and extinction. Using life-history theory and incorporating uncertainty into a modified Euler-Lotka model, the maximum intrinsic rates of population increase (rmax) were estimated for nine species from four families of Rhinopristiformes, using four different natural mortality estimators. Estimates of mean rmax, across the different natural mortality methods, varied from 0.03 to 0.59 year⁻¹ among the nine species, but generally increased with increasing maximum size. Comparing these estimates to rmax values for other species of chondrichthyans, the species Rhynchobatus australiae, Glaucostegus typus, and Glaucostegus cemiculus were relatively productive, while most species from Rhinobatidae and Trygonorrhinidae had relatively low rmax values. If the demand for their high-value products can be addressed then population recovery for some species is likely possible, but will vary depending on the species.
Chapter
Marine recreational fishing is a popular sport that people in many countries performed, it especially in the Arabian Gulf and sea of Oman areas, where the topography of the region promotes such activity. With the boom of this sport as the technology of the fishing boats has developed, significant impacts of performing this activity became obvious, and management of its effects need to be implemented. Several countries have introduced different methods to estimates the catch being done by the recreational fishing boat so the total national fishing will be managed correctly. Other countries have gone further than this step and recognized the biological impacts that the recreational fishing can exert on the marine environment and put the remedies kerb the effects of these impacts as much as possible. In the Arabian Gulf and Sea of Oman areas, the biological impacts have not been identified, and no legislation of any sort has been introduced to reduce or to halt the effects of the influences of the recreational fishing. In the present chapter, a short review of the recreational fishing was given together with a short account about the status of the recreational fishing at both the Arabian Gulf and sea of Oman areas. Latter, the biological influences of the entertaining fish catching were discussed and at the end of the chapter several recommendations were given so the policy makers at the countries in the areas studied will consider in the next round of management of the fisheries in their countries.
Chapter
A total of 138 chondrichthyan species—11% of the world’s known species—are currently known to occur in the waters surrounding the Arabian Peninsula, including 68 sharks from 22 families and 41 genera, 68 rays from 14 families and 33 genera, and two chimaeras from one family and one genus. Of these, 29 species are endemic to the region. The chondrichthyan species assemblage in the Arabian Sea and its adjacent waters do not reflect global shark and ray diversity, with some orders (e.g., Carcharhiniformes, Myliobatiformes, and Rhinopristiformes) very well represented, other taxa (e.g., families Squalidae and Rajidae) poorly represented, and Squatiniformes (angel sharks) entirely absent. Almost all chondrichthyan species found in these waters are heavily impacted by artisanal and industrial fisheries as well as coastal development. In fact, a recent regional IUCN Red List of Threatened Species assessment indicated that over half of them were threatened with extinction. These include species listed on the appendices of both the Convention on the International Trade of Endangered Species of Flora and Fauna and the Convention on the Conservation of Migratory Species of Wild Animals. The lack of overall fisheries management or enforcement of existing measures is a major issue and actions need to be immediately taken to ensure the long-term survival of most chondrichthyan species in the Arabian seas.
Chapter
This chapter highlights the fact that achieving sustainability in fisheries is a challenging task as it is influenced by the values, interests, incentives and attitudes of the actors involved, as well as institutional arrangements, among others. This chapter provides strategic insights into the issues and challenges pertaining to fisheries sustainability at the local and regional level. Evidence from the literature review confirms that the conservation and effective management of fisheries resources is unlikely, particularly when (1) fisheries resources are shared by countries with no clear ownership, (2) the enforcement of fisheries regulations is weak that results in noncompliance behavior, and (3) institutional arrangements and performance are not at their best level. The highlighted issues are a global phenomenon. In this context, a practical option to achieve sustainability in fisheries within territorial waters and beyond is to create cooperative arrangements which are transparent and operational in their true sense. The principal message of this chapter is that to achieve fisheries sustainability, “business as usual” is not an option, as the issue of fisheries law enforcement, noncompliance, and sustainability will continue to be the national, regional and international policy agenda in the future.
Article
Full-text available
Despite the large size and economic value of the species, populations of oceanic manta ray (Mobula birostris) are often poorly studied and almost completely undescribed in the Red Sea. Here, photo‐identification (photo‐ID) was used to provide the first description of M. birostris movement patterns and population demographics for the northern Red Sea. Images collated from social media, researchers, and photo‐ID databases from 2004 to 2021 identified 267 individual M. birostris from 395 sightings in Egypt, Israel, Jordan, Saudi Arabia, and Sudan. Sexual parity was observed in the population with 134 females, 111 males, and 22 individuals of undetermined sex. Nearly half of the individuals in this study were first identified through social media searches, highlighting the value of the sightings data collected by the public. The regular presence of juveniles in Sharm el‐Sheikh, Egypt, indicates that this area is a potential nursery, which is the second identified for this species globally and the first in the Indo‐Pacific. Encounter data from this study recorded the first known movements of juvenile M. birostris and demonstrate that they can travel long distances of at least 525 km. Within the recorded population, 24.7% (n = 67) of individuals were resighted, including 21 oceanic manta rays that were encountered in more than one location. These records reveal long‐distance migrations of up to 700 km and confirm the international connectivity of M. birostris in the Red Sea. The lagged identification rate data are best fitted with an open‐population model, implying that the northern Red Sea is represented by one well‐mixed population. The baseline data presented here should encourage the expansion of directed research and citizen science initiatives for M. birostris. Increased knowledge of movement patterns and site use will be crucial to successfully protecting this endangered species in a region characterized by high levels of shipping traffic, unregulated fisheries, and extensive coastal development.
Article
Full-text available
The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes-sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world's ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery.
Article
Full-text available
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 fishers’ 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.
Article
Full-text available
The northwestern Indian Ocean harbors a number of larger marine vertebrate taxa that warrant the investigation of genetic population structure given remarkable spatial heterogeneity in biological characteristics such as distribution, behavior, and morphology. Here, we investigate the genetic population structure of four commercially exploited shark species with different biological characteristics (Carcharhinus limbatus, Carcharhinus sorrah, Rhizoprionodon acutus, and Sphyrna lewini) between the Red Sea and all other water bodies surrounding the Arabian Peninsula. To assess intraspecific patterns of connectivity, we constructed statistical parsimony networks among haplotypes and estimated (1) population structure; and (2) time of most recent population expansion, based on mitochondrial control region DNA and a total of 20 microsatellites. Our analysis indicates that, even in smaller, less vagile shark species, there are no contemporary barriers to gene flow across the study region, while historical events, for example, Pleistocene glacial cycles, may have affected connectivity in C. sorrah and R. acutus. A parsimony network analysis provided evidence that Arabian S. lewini may represent a population segment that is distinct from other known stocks in the Indian Ocean, raising a new layer of conservation concern. Our results call for urgent regional cooperation to ensure the sustainable exploitation of sharks in the Arabian region.
Article
Full-text available
Landing site and market surveys of sharks landed along the Arabian Gulf coast of the United Arab Emirates were undertaken between October 2010 and September 2012 to obtain biological data from this artisanal fishery. Data were collected on the size and sex of 12 482 individuals representing 30 species. Maximum sizes of Carcharhinus sorrah, C. amblyrhynchoides and Hemipristis elongata were extended by at least 300 mm total length (TL) compared with published global maxima. The size at 50% maturity was determined for males of five species and this indicated that the males of smaller shark species (<1 000 mm maximum TL) in the fishery were largely mature. For many species, including Loxodon macrorhinus and Mustelus mosis, overall sex ratios were male-biased, indicating that sexual segregation is likely in those species. Furthermore, sex ratios for several species, such as Rhizoprionodon acutus, showed differences across seasons. Overall, the landings contained a high proportion of juveniles, causing concerns about the sustainability of this fishery. Biological parameters of a number of species differed from those recorded earlier for the region, demonstrating a need for additional local data collection to support the development of management measures.
Article
Full-text available
1. Devil rays (genus Mobula) are pelagic elasmobranchs widely distributed throughout tropical, subtropical and warm-temperate waters. Their occurrence and distribution remains poorly documented in the Arabian Seas region. A review is provided of species occurrence in these water bodies along with a synthesis of regional information on their biology and ecology. 2. Based on the available evidence, five Mobula species occur in the region (M. eregoodootenkee, M. japonica, M. kuhlii, M. tarapacana, and M. thurstoni). Of these, three (M. eregoodootenkee, M. tarapacana and M. thurstoni) were found to occur in the Red Sea, and three (M. eregoodootenkee, M. japanica, and M. kuhlii) were found to occur in the Arabian/Persian Gulf. Mobula japanica and M. kuhlii are reported here for the first time in Gulf waters. All five species were found in the Indian Ocean waters between the Gulf of Aden and Pakistan. 3. To address the still uncertain taxonomy of M. kuhlii, a redescription of this species is provided based on a sample of fresh specimen material. 4. Mobula diabolus is a nomen ambiguum, never used to unambiguously designate any newly described species, and its use should be avoided. 5. Considering the life-history traits that make these species particularly vulnerable to fishing pressure, current levels of exploitation in by-catch fisheries are unlikely to be sustainable, despite the fact that the trade in gill plates does not seem to be prevalent in this region. Critical knowledge gaps unfortunately still exist, crippling effective management and conservation actions.
Book
Full-text available
This review focuses on the 26 top shark-fishing countries, areas and territories determined as those reporting at least 1 percent of global shark catches during the decade from 2000 to 2009 and ten RFMOs. Eighty-four (84) percent of the global shark catches reported to FAO from 2000 to 2009 was from the 26 top shark-fishing countries, areas and territories. Overall, global reported annual shark catches during this decade show a significant decline of almost 20 percent from about 900 000 tonnes to about 750 000 tonnes. The review shows that 18 of the 26 top shark fishing countries, areas and territories have adopted an NPOA Sharks and that an additional 5 of these countries are in the process of adopting or developing such a plan. Among the most commonly adopted management measures for sharks are shark fin measures; but other regulations have also been implemented such as closed areas and season, by-catch/discard regulations, protected species, total allowable catches (TAC) and quotas, special reporting requirements and others. Data collection and research on sharks is lacking in many regions. Overall, the reporting of shark catches to FAO has improved in the last decade. Shark catches reported at species level doubled from 14 percent in 1995 to 29 percent in 2010. Most of the top shark-fishing countries, areas and territories have taken steps to combat illegal, unreported and unregulated (IUU) fishing, either by signing the FAO Port State Measures Agreement (PSMA) (46 percent) or at least by adopting an NPOA IUU or similar plan (23 percent). Only five (20 percent) of the top 26 shark-fishing countries, areas and territories have not adopted an NPOA Sharks, signed the PSMA or implemented an NPOA IUU. Nonetheless, in quite a few countries the effective implementation of MCS schemes is problematic, often because of a lack of human and financial resources. All but one of the top shark-fishing countries, areas and territories are members of at least one RFMO. In particular, shark measures adopted by tuna bodies are binding in their areas of competence for all their member States that have not objected to the measure in question. The array of shark measures adopted by the RFMOs may vary from binding recommendations or resolutions to non-binding measures, as in the case of the Commission for the Conservation of Southern Bluefin Tuna (CCSBT). They include shark fin measures, catch and gear regulations, prohibited species, area closures, reporting requirements and research programmes. This means that in all but one area covered by RFBs there are internationally binding shark measures in place for high seas fisheries.
Article
Full-text available
An 829-bp fragment of the NADH dehydrogenase subunit 2 (NADH2) gene was used to assess the taxonomic statusof 1487 elasmobranch specimens, representing 52 putative species. Strong evidence was found for the existence of an undescribed Echinorhinus species and for cryptic speciation within Rhynchobatus djiddensis. The results also provide strong molecular support for the existence of two previously reported, but undescribed, guitarfish species.Potential, but less conclusive, cryptic lineage diversification was also noted in Carcharhinus leucas, Loxodon macrorhinus, Iago omanensis and Gymnura poecilura. A complex situation was found in the genus Himantura, with potentially three distinct lineages evident, one of which is probably an undescribed species, in the H. gerrardi complex. One dasyatid specimen could not be identified, but appears to be closely related to Dasyatis ushiei, while Himantura leoparda and Carcharhinus longimanus are reported from Oman for the first time. The results of the present study also reinforce previously reported geographical divisions within certain putative species, which has important implications for fishery management and conservation.
Chapter
Full-text available
Chapter
Full-text available
The status of coral reefs bordering the Red Sea and Gulf of Aden is generally good, with live hard coral cover averaging 20-50%. There are predominantly fringing reefs bordering the coasts of Djibouti, Egypt, Saudi Arabia, Sudan and Yemen. Atolls and pinnacle reefs occur mainly in the central and southern Red Sea. However, technical reports, personal observations and comparative data show recent decreases in live coral cover. Fish populations are also declining and there have been several small outbreaks of the crown-of-thorns starfish (COTS), some local bleaching events and an increase in bioeroding organisms such as the urchin Diadema setosum and the coral eating gastropods Drupella and Coralliophila. Threats to coral reefs differ within the region, and are continuously increasing with the increasing rate of coastal development. The major threats are land filling, dredging, sedimentation, sewage discharge, and effluents from desalination plants. In major tourism areas, there is physical damage by tourists and boats anchors. Fishing pressure is constantly increasing throughout the region to satisfy demands of growing and more affluent populations. Most countries have legislation for reef conservation and additional national laws and multinational agreements have been adopted by the countries with assistance of the Regional Organisation for the Conservation of the Environment of the Red Sea and Gulf of Aden (PERSGA). However, the implementation of these laws is difficult and completely lacking in remote areas. There is a need for enforcement of national and international laws, development of public awareness programs and the adoption of sustainable management strategies to reverse the current trend in deterioration of the environment.
Article
Full-text available
Global chondrichthyan (shark, ray, skate and chimaera) landings, reported to the United Nations Food and Agriculture Organization (FAO), peaked in 2003 and in the decade since have declined by almost 20%. In the FAO's 2012 ‘State of the World's Fisheries and Aquaculture’ report, the authors ‘hoped’ the reductions in landings were partially due to management implementation rather than population decline. Here, we tested their hypothesis. Post-peak chondrichthyan landings trajectories from 126 countries were modelled against seven indirect and direct fishing pressure measures and eleven measures of fisheries management performance, while accounting for ecosystem attributes. We found the recent improvement in international or national fisheries management was not yet strong enough to account for the recent decline in chondrichthyan landings. Instead, the landings declines were more closely related to fishing pressure and ecosystem attribute measures. Countries with the greatest declines had high human coastal population sizes or high shark and ray meat exports such as Pakistan, Sri Lanka and Thailand. While important progress had been made, country-level fisheries management measures did not yet have the strength or coverage to halt overfishing and avert population declines of chondrichthyans. Increased implementation of legally binding operational fisheries management and species-specific reporting is urgently required to avoid declines and ensure fisheries sustainability and food security.
Article
Full-text available
Although fish fauna in the Arabian/Persian Gulf have been studied for decades, shark diversity has only been recently investigated in the region. Here, we present a first comprehensive account of shark diversity from the United Arab Emirates based on fishery-dependent data collected at market and landing sites over a two-year period of field sampling. Landings across the country were dominated by carcharhinids, and six species were found to be most abundant, including the spot-tail shark, Carcharhinus sorrah, and the milk shark, Rhizoprionodon acutus, contributing 31.8 % and 29.9 %, respectively, of the total number of sharks. While observed landings varied among regions and across seasons, results showed that shark landings were dominated by small-sized species, which may be a reflection of overexploitation. We are now expanding the existing checklist of shark species in the Persian Gulf from 27 to 31, having utilized both morphological identification and genetic barcoding in validating the existence of the grey bamboo shark, Chiloscyllium griseum; the tawny nurse shark, Nebrius ferrugineus; the silky shark, Carcharhinus falciformis; and the sandbar shark, Carcharhinus plumbeus, in these waters. This inventory provides an urgently needed assessment of current regional diversity patterns that can now be used as a baseline for future investigations evaluating the effect of fisheries on shark populations. Results emphasize the need for research on life history traits of the various species in order to determine their regional conservation status, but also reveal that a precautionary approach to conservation will be necessary to mitigate anthropogenic impacts.
Article
Full-text available
New biological data relevant to the conservation of the rare and threatened shark Carcharhinus leiodon are presented, based on specimens sampled in fish markets in Kuwait, the UAE and Yemen. The maximum size of this species is extended to 1648 mm total length (TL); females are mature by at least 1312 mm TL and demonstrate placental viviparity with litters of 4–6 embryos. In the north-western Persian Gulf there is evidence that parturition occurs in spring when embryos are ,350–515 mm TL, with at least some neonate individuals probably remaining in the area through the summer. Further records of C. leiodon from the western Arabian Sea indicate that adults are present in this region throughout the year. Landings of C. leiodon apparently caught in the eastern Persian Gulf may extend the highly fragmented known distribution of this species. Contrary to an earlier study, the first detailed examination of dissected adult C. leiodon jaws revealed that fine serrations are present on upper teeth, and characters are provided to separate the dentition and jaws of C. leiodon from congeners. The stomach of an adult C. leiodon contained bentho-demersal fish, and an individual with fin abnormalities is noted.
Article
Full-text available
The nature of small-scale fisheries is frequently described as complex. This complexity is particularly true for the least developed countries, such as Yemen, in which natural resources management is challenged by rapid population growth, high unemployment rates, and chronic underdevelopment. This study presents the current fisheries management regime and analyzes its components to examine how appropriate the current strategy is in addressing conservation needs while sustaining the socio-economic benefits obtained from fisheries. The weak enforcement and low compliance and the widespread illegal, unreported, and unregulated fishing, suggest the need to restructure the fisheries management system. Moreover, for any future policy reforms, it will be necessary to consider introducing appropriate anti-corruption measures and policies to improve transparency and accountability. The fishery managers need also to adopt the precautionary approach widely, using the best available information, until results from research become available.
Book
Full-text available
This field guide covers the major resource groups likely to be encountered in the fisheries of Kuwait, Eastern Saudi Arabia, Bahrain, Qatar, and the United Arab Emirates. It includes marine plants, shrimps, lobsters, crabs, bivalves, gastropods, cephalopods, sharks, batoid fishes, bony fishes, sea snakes, sea turtles, sea birds, and marine mammals. In order to serve as a tool for ecological and biodiversity studies, all species know from the Gulf of certain groups are included. These include the sharks, batoid fishes, bony fishes, sea turtles, and marine mammals. Each resource group is introduced by a general section on technical terms and measurements pertinent to that group and an illustrated guide to higher taxonomic groups when relevant. Species are then treated in a subsequent guide that includes scientific nomenclature, common English and Arabic names where available, size information, information on habitat, biology, and fisheries, diagnostic features, and one or more illustrations, some of which are included in colour. The guide is fully indexed and a list of references is appended.
Article
Full-text available
The bushmeat trade, or the illegal acquisition and exchange of wild meat, has long been recognised as a severe problem in forest biomes, but receives little attention in savannas, perhaps due to a misconception that bushmeat hunting is a low-impact subsistence activity. Though data on impacts are scarce, indications are that bushmeat hunting is a widespread problem in savannas, with severe impacts on wildlife populations and wildlife-based land uses. The impacts of the bushmeat trade in savannas vary from edge-effects around protected areas, to disproportionate declines of some species, to severe wildlife declines in areas with inadequate anti-poaching. In some areas, bushmeat contributes significantly to food security, but these benefits are unsustainable, and hunting is wasteful, utilising a fraction of the wildlife killed or of its financial value obtainable through tourism, trophy hunting and/or legal game meat production. The bushmeat trade appears to be becoming increasingly commercialised due to elevated demand in rural areas, urban centres and even overseas cities. Other drivers for the trade include human encroachment of wildlife areas; poverty and food insecurity; and inadequate legal frameworks to enable communities to benefit legally from wildlife, and to create incentives for people to desist from illegal bushmeat hunting. These drivers are exacerbated by inadequate wildlife laws and enforcement and in some areas, political instability. Urgent efforts are needed to address these drivers and raise awareness among local and international governments of the seriousness of the threat. Failure to address this will result in severe wildlife declines widely in African savannas, with significant ecological, economic and social impacts.
Article
Full-text available
The impact of fishing on chondrichthyan stocks around the world is currently the focus of considerable international concern. Most chondrichthyan populations are of low productivity relative to teleost fishes, a consequence of their different life-history strategies. This is reflected in the poor record of sustainability of target shark fisheries. Most sharks and some batoids are predators at, or near, the top of marine food webs. The effects of fishing are examined at the single-species level and through trophic interactions. We summarize the status of chondrichthyan fisheries from around the world. Some 50% of the estimated global catch of chondrichthyans is taken as by-catch, does not appear in official fishery statistics, and is almost totally unmanaged. When taken as by-catch, they are often subjected to high fishing mortality directed at teleost target species. Consequently, some skates, sawfish, and deep-water dogfish have been virtually extirpated From large regions. Some chondrichthyans are more resilient to fishing and we examine predictions on the vulnerability of different species based on their life-history and population parameters. At the species level, fishing may alter size structure and population parameters in response to changes in species abundance. We review the evidence for such density-dependent change. Fishing can affect trophic interactions and we examine cases of apparent species replacement and shifts in community composition. Sharks and rays learn to associate trawlers with food and feeding on discards may increase their populations. Using ECOSIM, we make some predictions about the long-term response of ecosystems to fishing on sharks. Three different environments are analysed: a tropical shelf ecosystem in Venezuela, a Hawaiian coral reef ecosystem, and a North Pacific oceanic ecosystem. (C) 2000 International Council for the Exploration of the Sea.
Article
Full-text available
The Arabian Gulf (also known as Persian Gulf and ROPME Sea) represents an extremely important economic, political and strategic aquatic resource. Although the Gulf region is known world wide for its oil-gas deposits and production, very little is known about its ecosystem health, food web dynamics, fisheries, biodiversity and sustainability. The present study reviews and highlights the major anthropogenic stressors which threaten the marine and coastal ecosystems of the Gulf. The Arabian Gulf environment lacks the holistic, ecosystem-based research and monitoring that have been conducted in other marine ecosystems. There is a need for multi-disciplinary, multi-trophic and multi-agency international investigations including the application of emerging technology. Such an integrated strategy is urgently needed to save the rapidly changing marine ecosystems from the impact of rapid and vigorous coastal development across the entire Gulf region. The necessity of developing and implementing ecosystem health agreements between the various riparian countries is emphasized for expeditious protection, conservation and management of this precious but threatened natural heritage.
Article
Full-text available
We report on results of a trawl survey during 2003^2004 to assess the abundance of demersal ¢sh resources in the Persian Gulf and Oman Sea. Samples were taken at a total of 316 trawl stations selected following a strati¢ed random procedure. Catch rates (catch per unit area, CPUA) and total biomass were estimated. Total demersal ¢sh biomass was estimated to be approximately 73,000 tonnes in Persian Gulf waters and approximately 39,000 tonnes in the Oman Sea. The lowest CPUA was recorded in the west of the study area (stratum A, approximately 1700 kg/n.m. 2) and the highest in the east (stratum Q, 13943.4 kg/n.m. 2), although density of commercially important species was higher in the central area (stratum K). Catch rate and biomass varied signi¢cantly in relation to seabed depth. Commercially impor-tant demersal species made up around 60% of the estimated total biomass. The most abundant species groups were rays, cat¢sh, grunts, nemipterids and carangids. Several important species (e.g. silver pomfret, croakers and sharks) appear to have declined since the late 1970s while others, such as rays and cat¢sh, have increased.
Article
The main purposes are to collate information of the region, to review marine systems and processes in the intertidal and shallow sublittoral parts of the Arabian seas, and to highlight human utilisation and environmental consequences. The first section presents the geological, geographical, climatic and oceanographic background to the area. The second section examines what is known of the region's marine communities, interpreting the relationships between the marine systems and physical conditions for: reefs and coral communities; coral reef fish assemblages; other reef components and processes; seaweeds and seasonality; seagrasses and other dynamic substrates; intertidal areas - mangal associated ecosystems, marshes, sabkha and beaches; and the pelagic system. The next section synthesizes and concludes the biogeographical material and interprets the effects of natural stress on the biota. The final section describes and discusses the human use and management of the region, including fisheries. -after Authors
Article
A new whipray, Himantura randalli sp. nov., described from material collected off Bahrain, Kuwait and Qatar, appears to be endemic to the Persian Gulf. It has been frequently confused with forms of the more widely distributed whipray Himantura gerrardi Gray and other presently unidentified species from the Indian Ocean. Himantura randalli sp. nov. is distinguished from these species by a combination of characters, i.e. disc shape, morphometrics, squamation (including its rapid denticle development and denticle band shape), plain dorsal disc coloration, and whitish saddles on a dark tail in young. It is a medium-sized whipray with a maximum confirmed size of 620 mm disc width (DW) and a birth size of around 150-170 mm DW. Males mature at approximately 400 mm DW. Himantura randalli sp. nov. is relatively abundant in the shallow, soft-sedimentary habitats of the Persian Gulf from where it is commonly taken as low-value or discarded bycatch of gillnet and trawl fisheries.