Article

The trade in sharks and their products in the United Arab Emirates

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  • Elasmo Project
  • Free lance Ottawa, Canada
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... Shallow gulfs and seas often support substantial fisheries that in turn feed a wealth of seabirds including cormorants (Nelson 2005). Increasing demand for fish has led to increased commercial fish exploitation in these regions (Jabado et al. 2015). The Arabian Gulf region has undergone rapid change in the last three decades due to the discovery of oil in most of the Gulf States (Shihab 2001). ...
... The Arabian Gulf region has undergone rapid change in the last three decades due to the discovery of oil in most of the Gulf States (Shihab 2001). This has led to environmental degradation, along with increased fishing activities that are supporting the influx of people moving into the region (Jabado et al. 2015). Fishing in the Arabian Gulf is mainly targeting pelagic and demersal fish (Carpenter et al. 1997;Grandcourt 2012), although the true extent of the fisheries activities may not be fully reported (Jabado et al. 2015). ...
... This has led to environmental degradation, along with increased fishing activities that are supporting the influx of people moving into the region (Jabado et al. 2015). Fishing in the Arabian Gulf is mainly targeting pelagic and demersal fish (Carpenter et al. 1997;Grandcourt 2012), although the true extent of the fisheries activities may not be fully reported (Jabado et al. 2015). ...
Chapter
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Socotra Cormorants (Phalacrocorax nigrogularis) are regionally endemic, vulnerable seabirds limited to the Arabian Gulf and Sea of Oman regions. Global populations have undergone catastrophic declines, with several major colonies gone completely extinct in the central western Arabian Gulf. Major threats include breeding habitat loss due to oil exploitation, disturbance at breeding colonies, fisheries by catch and occasional hunting. Six of 12 large colonies have become extinct in the United Arab Emirates. Colonies in the western Gulf seemingly have suffered considerably, with much lower numbers compared to historic records. In comparison, the single colony on Siniya Island, Umm Al Quwain, in the eastern Arabian Gulf is arguably the largest in the UAE and possibly the entire Gulf with an increasing population of about 35,000 breeding pairs. Breeding studies indicate variable reproductive success possibly linked with habitat features, weather, diet and impact of predators. Planted trees on the island provide protection from soaring temperatures early in the breeding season and improve breeding performance. The island hosts native Red Foxes (Vulpes vulpes) and feral cats (Felis catus) that have a negative impact on the breeding performance. Additionally, ample evidence exists of conflict with fishermen. Many birds die annually to fishermen's nets or lines and fishermen generally perceive them to be competitors. Diet studies indicate that fish taken by cormorants have almost no overlap with commercially important species. The island is subjected to periodic disturbance by fishermen collecting sea grass from lagoons. Additionally, the island is littered with a wide range of plastic and other debris. Current trends in the population could be offset if any or all of the threats continue to increase. Conservation and management of this population must focus on removing plastics, eliminating disturbance during breeding seasons, engaging local fishermen to reduce by-catch mortality, protecting coastal areas to safeguard foraging sites, and creating awareness.
... Yet, after nearly a decade with just three shark species being listed on CITES Appendix II (Table 1), three listing proposals involving five shark species passed at the CoP16 in 2013, taking effect in late 2014 (Clarke, 2014). This was a significant change because the species listed prior to 2013 were fully protected in many jurisdictions prior to listing (Fergusson et al., 2009;Fowler, 2000;Fowler, 2005b), while the species listed at CoP16 were a larger part of legal landings in many parts of the world (Chuang, Hung, Chang, Huang, & Shiao, 2016a;Jabado et al., 2015;Tolotti et al., 2015). In 2016, at Cop17, two more proposals involving four species were adopted and took effect in late 2017 (Table 1). ...
... Hong Kong Special Administrative Region of the People's Republic of China (from now on referred as Hong Kong) is one of the largest shark fin trade hubs in the world, importing a total of 5,528,862 kg in 2015, and annually trading with an average of 83 exporting nations (Dent & Clarke, 2015;. Surveys in Hong Kong in 1999-2001(Clarke, Magnussen, Abercrombie, McAllister, & Shivji, 2006, and a few of their top trading partners (Chuang, et al. 2016a;Jabado et al., 2015;Sembiring et al., 2015) all showed that fins of several species listed at CoP16 were commonly traded prior the listings taking effect. The first objective of the present study was to assess the global position of Hong Kong as legal importer of fins from CITES listed species according to CITES trade records. ...
... Red letters/numbers and shark symbols depict CoP16 listed species (took effect late 2014), yellow letters/numbers and shark symbols depict CoP17 listed species (took effect October 2017) species to Hong Kong (Figure 1). Many exporting nations previously known to land these species were not among those to report trade, again, suggesting low compliance with CITES reporting requirements in 2015-2016 (Chuang, Hung, Chang, Huang, & Shiao, 2016b, 2016aJabado et al., 2015;Sembiring et al., 2015). Relatively low compliance with CITES regulations, especially in the initial phase of implementation, is documented in other taxa including seahorses (Foster, Wiswedel, & Vincent, 2014), tigers, rhinoceros (Cheung, 1995), and turtles (Rehman, Jafar, Ashraf Raja, & Mahar, 2015). ...
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.
... Shallow gulfs and seas often support substantial fisheries that in turn feed a wealth of seabirds including cormorants (Nelson 2005). Increasing demand for fish has led to increased commercial fish exploitation in these regions (Jabado et al. 2015). The Arabian Gulf region has undergone rapid change in the last three decades due to the discovery of oil in most of the Gulf States (Shihab 2001). ...
... The Arabian Gulf region has undergone rapid change in the last three decades due to the discovery of oil in most of the Gulf States (Shihab 2001). This has led to environmental degradation, along with increased fishing activities that are supporting the influx of people moving into the region (Jabado et al. 2015). Fishing in the Arabian Gulf is mainly targeting pelagic and demersal fish (Carpenter et al. 1997;Grandcourt 2012), although the true extent of the fisheries activities may not be fully reported (Jabado et al. 2015). ...
... This has led to environmental degradation, along with increased fishing activities that are supporting the influx of people moving into the region (Jabado et al. 2015). Fishing in the Arabian Gulf is mainly targeting pelagic and demersal fish (Carpenter et al. 1997;Grandcourt 2012), although the true extent of the fisheries activities may not be fully reported (Jabado et al. 2015). ...
Article
Socotra Cormorants (Phalacrocorax nigrogularis) are a regionally endemic, locally abundant species restricted primarily to the Arabian Gulf and coastal Oman. The species has declined since the 1980s and is currently categorized as Vulnerable by the International Union for Conservation of Nature. Breeding phenology, breeding performance and variation in breeding population size were studied on Siniya Island, the largest colony in the United Arab Emirates. Laying dates were between 13 September and 6 October during the 2011- 2015 breeding seasons. Incubation was estimated to be 24-27 days, and clutch size ranged from 2.21-2.79 eggs/ nest. Hatching success ranged from 58.71 ± 5.85 in 2011 to 81.76 ± 4.86% in 2012. The total population varied over the 5 years of study from 28,152 ± 3,780 pairs in 2011 to 41,568 ± 3,761 pairs in 2014. Population estimates using density-area calculations were closely aligned with ground counts. The use of a drone with a mounted camera greatly improved the counts in 2015. The Socotra Cormorant breeding population on Siniya Island appears to be stable over the short term with annual fluctuations comparable to other cormorant species. Thus, our data suggest the breeding population on Siniya Island could have surpassed that of other colonies in the Arabian Gulf, underscoring its global significance.
... Saudi Arabian samples were obtained from one fish market only (Jeddah), but landings at this site originated from fishing grounds spanning the country's entire Red Sea coast (Spaet and Berumen 2015) ( Fig. 1). Samples from the UAE were collected from landing and market sites in Abu Dhabi, Dubai, Sharjah, and Ras Al Khaimah as described in Jabado et al. (2014aJabado et al. ( , 2015. Samples from Oman were collected directly from landing sites along the Omani coast; samples from Bahrain were obtained at the wholesale market of the capital, Manama ( Fig. 1; Table S1). ...
... The fact that Arabian S. lewini, which comprise a large amount of the commercial harvest in the Arabian region (Jabado et al. 2015;Spaet and Berumen 2015), might represent a DPS raises a new layer of conservation concern and may warrant species-specific conservation actions under the Convention on International Trade in Endangered Species (CITES), Convention on the Conservation of Migratory Species of Wild Animals (CMS), and a re-evaluation of its IUCN Red List conservation status. Future research should focus on the identification of broader scale genetic breaks by sampling all four species further to the west and east of our sampling locations. ...
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.
... Most fishing is artisanal, contributing to 75% of total catches (Al-Abdulrazzak et al., 2015), and fisheries are multi-species and multi-gear (e.g. Jabado et al., 2015). Wire traps (gargours) are the most dominant fishing gear used in the Arabian Gulf (Amer and Al-Gaber, 2006;Chen et al., 2012;Hartmann, 2017), targeting commercially valuable demersal species, such as groupers (Family Epinephelidae), emperors (Lethrinidae), grunts (Haemulidae), snappers (Lutjanidae) and jacks (Carangidae) (Siddeek and Fouda, 1999;Amer and Al-Gaber, 2006;Chen et al., 2012;Hartmann, 2017). ...
... The state of fisheries across the region varies, but many fish stocks are now considered overfished (Grandcourt, 2012;Jabado et al., 2015). The UAE is the second largest country in terms of catches, with 12% of recorded catch from the Arabian Gulf (Al-Abdulrazzak et al., 2015). ...
Article
Underwater camera systems can be a valuable tool for evaluating fish assemblages and estimating relative abundance of stock, assessing behaviour of marine species, and monitoring ecosystem change. Within the Arabian Gulf waters of the United Arab Emirates (UAE), overall fish species diversity and distribution and frequency of occurrence were determined from baited underwater video (BUV) and trap video in commercial fish traps (gargours). A total of 75 species or species groups were recorded, with the highest species diversity recorded on BUV (70 species or species groups, compared with 58 and 55 species or species groups on trap video and in trap catch, respectively). Most frequently recorded species included Nemipterus peronii, catfishes (Netuma spp.), Echeneis naucrates, Himantura uarnak, and Lethrinus microdon. Sightings of 8 key species of commercial interest and Echeneis naucrates were found to be similar between season and method, but observations of some species appeared to vary by survey area (inshore, offshore trawlable, offshore untrawlable). Arrival time for key species to reach maximum numbers (MaxN) occurred between 50 and 100 min of trap deployment, indicating that the video observation length (up to 180 min) and trap deployment length (about 360 min) were appropriate for estimating abundance. Escapement within the observed period (about 180 min) varied from zero for Diagramma pictum and Lethrinus borbonicus to 13% for Epinephelus coioides and 20% for L. lentjan. Escapement post video reached 71% for Lethrinus borbonicus. The presence of the commercially important and predatory fish Epinephelus coioides appeared to affect the catchability of fishes with behaviours that included territoriality and predation.
... Hence, our finding was inconsistent with the available landing data in Sri Lanka (Hasarangi et al., 2012;Herath et al., 2019). Several genetic studies conducted in adjacent waters near Sri Lanka showed either an absence of blue sharks or low abundance (Haque et al., 2019;Jabado et al., 2015), suggesting the potential decline of blue shark stock. Although Prionace glauca is not considered to be a globally threatened species in the IUCN red list, where it is categorized as a Near Threatened (NT). ...
... Hence, it is worth highlighting that an immediate stock analysis of blue shark in the Indian Ocean is urgently needed. A large number of threatened species commonly occur in the elasmobranch fishery and many studies have revealed a similar result (as in many threatened species) by using DNA barcoding approaches (Bernardo et al., 2020;Feitosa et al., 2018;Haque et al., 2019;Jabado et al., 2015;Liu et al., 2013). Based on the results of this study, 62 % of tissues were classified as threatened shark species (CR or VU) by IUCN (Fig. 5). ...
Article
Sharks are considered to be top predators in marine ecosystems. Due to the high market value of shark fins, fishing pressure on these top predators has increased significantly and they are currently considered to be a threatened marine vertebrate group. Sri Lanka is an island nation with 21 major fish harbours in operation and one of the top 20 shark fishing countries. With an increasing local and global demand for shark meat and fins, the species consumed by Sri Lankans as well as species composition of the landing are in question because the identification of processed shark is difficult (e.g. fish filet) and there is a lack of species-specific landing data. In the present study, we applied a DNA barcoding approach to identify species composition of the shark catch in Sri Lanka. Shark tissue samples were collected in 2018 and 2019 from 10 fishing harbours and fish markets around Sri Lanka. In total, 330 out of 353 tissue samples were successfully barcoded and the results revealed 17 shark species corresponding to five families including Alopias superciliosus, Carcharhinus amblyrhynchoides, C. falci-formis, C. leucas, C. limbatus, C. longimanus, C. melanopterus, C. sorrah, Chiloscyllium griseum, Hemipristis elongate, Loxodon macrorhinus, Paragaleus randalli, Prionace glauca, Rhizoprionodon oligolinx, R. acutus, Sphyrna lewini and Galeocerdo cuvier. Among them, C. falciformis (silky shark) is the most dominant (39.4 %). Variation in fishing area and fishing gear used could be the main determinants of species composition across localities. The results showed 62 % of shark species identified in this study are threatened globally based on IUCN categories. Surprisingly , two banned species, A. superciliosus and C. longimanus, were found with low abundance. The results of this study provide crucial information for improving the Sri Lankan shark management plan in the future. In addition, we suggest a regular assessment of shark landing species composition be implemented to monitor the efficiency of current management.
... The crucial moment when the species began to be differentiated at the molecular level was when Hebert and collaborators (2003) promoted the mitochondrial gene Cytochrome c oxidase subunit 1 (COI) as an effective "barcode" capable of identifying the species (Krishna & Francis, 2012). As it relates to the sharks and the use of the same vernacular term to report a wide range of species, DNA Barcoding has already been applied to provide forensic evidence of the fin trade in Morocco (Alison et al., 2018), United Kingdom (Hobbs et al., 2019), Canada, China (Steinke et al., 2017), Hong Kong (Clarke et al., 2006a, United Arab Emirates (Jabado et al., 2015), Australia (Holmes et al., 2009), Madagascar (Doukakis et al., 2011, and Indonesia (Sembiring et al., 2015). These molecular-based identification methods were also used to identify shark meat species in Peru (Velez-Zuazo et al., 2015), Costa Rica (O'Bryhim et al., 2017), Taiwan (Liu et al., 2013), United Kingdom (Hobbs et al., 2019), Guyana (Kolmann et al., 2017), United Arab Emirates (Jabado et al., 2015), Indonesia (Sembiring et al., 2015) and in some regions of Brazil (Rodrigues-Filho et al., 2009;Ramos, 2017;Staffen et al., 2017;Almerón-Souza et al., 2018;Bunholi et al., 2018;Feitosa et al., 2018;Calegari et al., 2019;Bernardo et al., 2020). ...
... As it relates to the sharks and the use of the same vernacular term to report a wide range of species, DNA Barcoding has already been applied to provide forensic evidence of the fin trade in Morocco (Alison et al., 2018), United Kingdom (Hobbs et al., 2019), Canada, China (Steinke et al., 2017), Hong Kong (Clarke et al., 2006a, United Arab Emirates (Jabado et al., 2015), Australia (Holmes et al., 2009), Madagascar (Doukakis et al., 2011, and Indonesia (Sembiring et al., 2015). These molecular-based identification methods were also used to identify shark meat species in Peru (Velez-Zuazo et al., 2015), Costa Rica (O'Bryhim et al., 2017), Taiwan (Liu et al., 2013), United Kingdom (Hobbs et al., 2019), Guyana (Kolmann et al., 2017), United Arab Emirates (Jabado et al., 2015), Indonesia (Sembiring et al., 2015) and in some regions of Brazil (Rodrigues-Filho et al., 2009;Ramos, 2017;Staffen et al., 2017;Almerón-Souza et al., 2018;Bunholi et al., 2018;Feitosa et al., 2018;Calegari et al., 2019;Bernardo et al., 2020). ...
... These methodologies have got a wide range application in different real life purposes including fisheries assessment (Ardura Planes, & Garcia-Vazquez, 2013;Ludwig, 2008). Jabado et al. (2015) reported about the utility of molecular techniques in identifying morphologically challenging shark species and their body parts. Wong and Hanner (2008) identified seafood substitution in North American markets and demonstrated the role of DNA barcodes in addressing this issue. ...
Article
This study presents the molecular barcoding results of giant freshwater prawns and allied products collected from inland landing centres, markets and stores of Vembanad Lake (Kerala state, India) which is recognized as a natural abode for Macrobrachium rosenbergii. Prawns collected from landing centres of the lake could be easily identified as the above with their large size and morphological characters. There were certain ‘alien’ prawns and prawn products (headless shell on, peeled and deveined) traded in the markets and stores of this region as M. rosenbergii. Genotyping of all these samples using COI and 16S rRNA gene sequences confirmed the speciation of individuals from inland landing centres as M. rosenbergii, ‘alien’ prawns and certain prawn products as M. malcolmsonii. To ensure the same and to detect the presence of any other congeners of genus Macrobrachium inhabiting Vembanad Lake, additional homologous COI and 16S rRNA sequences available in NCBI were acquired and incorporated for molecular analyses. Results generated from NJ tree and genetic distance data confirmed the trade of non‐indigenous Macrobrachium species M. malcolmsonii in Kerala for the first time and its use as a species substituent for M. rosenbergii.
... Humans have depended on biodiversity for survival for millennia, but these anthropogenic activities are unfortunately altering and damaging ecosystems, causing alarming species extinction rates [1,2]. In particular, the ocean faces multiple threatspredominantly overexploitation for diverse commodities in international marketswhich puts marine biodiversity in a dire situation [2,3]. Over the last half-century, populations of pelagic sharks and rays have declined by over 70 per cent; and over a third of shark, ray, and chimaera species are now facing an elevated risk of extinction [4,5]. ...
Article
Wedgefishes (Rhinidae) and giant guitarfishes (Glaucostegidae) are amongst the most threatened marine taxa globally. Research was undertaken in Singapore, a globally significant trading hub for shark and ray products, between May 2019 (two months after they were proposed for listing on the Convention on International Trade in Endangered Species of Flora and Fauna (CITES)) and August 2019 (three months before listings entered into force). The study documents the composition of imports and landings, estimates the scale of the trade, describes the supply chain, and analyzes completeness of product labels through surveys in fishery ports and retail markets as well as informal interviews with traders. Of 590 individuals recorded at fishery ports, 215 from six species could be identified to the species-level. Rhynchobatus australiae was the most commonly encountered wedgefish species (66%) while only one species of giant guitarfish (Glaucostegus typus) was recorded. Individuals were primarily claimed to be imported from Indonesia and Malaysia. The high value of wedgefish fins was evident as a large proportion of individuals without fins (66%) were recorded. Businesses in Singapore were utilizing by-products of the fin trade which appeared to have a distinct supply chain. Traders noted declining supplies of wedgefishes and dried shark fins in recent years. Shark and ray products notably lacked information on species and country of origin on their labels. Findings here provide baseline data for determining the effectiveness of new trade controls and suggest that a multi-pronged approach with trade monitoring, additional traceability and labeling requirements, and enhanced fisheries management would conserve globally declining, wild populations.
... Despite legal protection, S. lewini is among the most landed shark species along the Saudi Arabian Red Sea coast [16]. Furthermore, S. lewini represents over 3% of all species traded in the Arabian Seas region [17]. At the same time, S. lewini populations in the western Indian Ocean appear fragmented with limited dispersal between the Arabian Seas region and other Indian Ocean regions [18]; yet, stock assessments and species-specific studies are missing in the area [19,20]. ...
Article
Full-text available
Background Despite being frequently landed in fish markets along the Saudi Arabian Red Sea coast, information regarding fundamental biology of the Scalloped hammerhead shark (Sphyrna lewini) in this region is scarce. Satellite telemetry studies can generate important data on life history, describe critical habitats, and ultimately redefine management strategies for sharks. To better understand the horizontal and vertical habitat use of S. lewini in the Red Sea and to aid with potential future development of zoning and management plans for key habitats, we deployed a pop-up satellite archival transmitting tag to track a single female specimen (240 cm total length) for a tracking period of 182 days. Results The tag was physically recovered after a deployment period of 6 months, thus providing the complete archived dataset of more than one million depth and temperature records. Based on a reconstructed, most probable track, the shark travelled a circular distance of approximately 1000 km from the central Saudi Arabian Red Sea southeastward into Sudanese waters, returning to the tagging location toward the end of the tracking period. Mesopelagic excursions to depths between 650 and 971 m occurred on 174 of the 182 days of the tracking period. Intervals between such excursions were characterized by constant oscillatory diving in the upper 100 m of the water column. Conclusions This study provides evidence that mesopelagic habitats might be more commonly used by S. lewini than previously suggested. We identified deep diving behavior throughout the 24-h cycle over the entire 6-month tracking period. In addition to expected nightly vertical habitat use, the shark exhibited frequent mesopelagic excursions during daytime. Deep diving throughout the diel cycle has not been reported before and, while dive functionality remains unconfirmed, our study suggests that mesopelagic excursions may represent foraging events within and below deep scattering layers. Additional research aimed at resolving potential ecological, physiological and behavioral mechanisms underpinning vertical movement patterns of S. lewini will help to determine if the single individual reported here is representative of S. lewini populations in the Red Sea.
... Despite legal protection, S. lewini is among the most landed shark species along the Saudi Arabian Red Sea coast [16]. Furthermore, S. lewini represents over 3% of all species traded in the Arabian Seas region [17]. At the same time, S. lewini populations in the western Indian Ocean appear fragmented with limited dispersal between the Arabian Seas region and other Indian Ocean regions [18]; yet, stock assessments and species-specific studies are missing in the area [19,20]. ...
Article
Background: Despite being frequently landed in fish markets along the Saudi Arabian Red Sea coast, information regarding fundamental biology of the Scalloped hammerhead shark (Sphyrna lewini) in this region is scarce. Satellite telemetry studies can generate important data on life history, describe critical habitats, and ultimately redefine management strategies for sharks. To better understand the horizontal and vertical habitat use of S. lewini in the Red Sea and to aid with potential future development of zoning and management plans for key habitats, we deployed a pop-up satellite archival transmitting tag to track a single female specimen (240 cm total length) for a tracking period of 182 days. Results: The tag was physically recovered after a deployment period of 6 months, thus providing the complete archived dataset of more than one million depth and temperature records. Based on a reconstructed, most probable track, the shark travelled a circular distance of approximately 1000 km from the central Saudi Arabian Red Sea southeastward into Sudanese waters, returning to the tagging location toward the end of the tracking period. Mesopelagic excursions to depths between 650 and 971 m occurred on 174 of the 182 days of the tracking period. Intervals between such excursions were characterized by constant oscillatory diving in the upper 100 m of the water column. Conclusions: This study provides evidence that mesopelagic habitats might be more commonly used by S. lewini than previously suggested. We identified deep diving behavior throughout the 24-h cycle over the entire 6-month tracking period. In addition to expected nightly vertical habitat use, the shark exhibited frequent mesopelagic excursions during daytime. Deep diving throughout the diel cycle has not been reported before and, while dive functionality remains unconfirmed, our study suggests that mesopelagic excursions may represent foraging events within and below deep scattering layers. Additional research aimed at resolving potential ecological, physiological and behavioral mechanisms underpinning vertical movement patterns of S. lewini will help to determine if the single individual reported here is representative of S. lewini populations in the Red Sea.
... dorsal, pectoral, caudal) of small-bodied species [<1 m total length (TL) at maturity, hereafter referred to as 'small species'], or juvenile specimens of large-bodied species (>1 m TL at maturity, hereafter referred to as 'large species'; Fields et al., 2017), from secondary fins (i.e. pelvic, anal, second dorsal) of large species, or any combination of these sources (Jabado et al., 2015). This is an important distinction to make because large body size is a predictor of increased extinction risk in elasmobranchs (Dulvy et al., 2014). ...
Article
The international fin trade is a major source of mortality for many threatened shark species but most of what it is known about this trade comes from assessments of large fins commanding high prices in trade hubs. There is growing international trade in ‘small, low‐value’ fins in Southeast Asia, which are used for inexpensive shark fin soup products. These fins could be derived from small species, juveniles of large species, or a combination of both. Resolving the species identification of these small fins has important conservation implications, because large sharks tend to be more vulnerable (VU) to overexploitation than small ones. Here we describe the first species‐specific assessment of the small, low‐value fins in the shark fin retail markets of Hong Kong. A total of 475 randomly collected samples were genetically identified using a portion of the cytochrome oxidase I, revealing at least 29 species. Around a third (34.5%) of the species found are in threatened International Union for the Conservation of Nature Red List categories, and 21.2% of the samples were from four species listed on Appendix II of the Convention on International Trade in Endangered Species (CITES). The size of the analyzed fins and the species composition found suggests that small fins come from a combination of small (62.9 %) and large (37.1%) species, with the majority of small fins coming from suspected juveniles of large species. We suggest the sources of most of these fins are likely to be multi‐species fisheries in shallow, coastal habitats used by large species and also occupied by small species. Our results represent the first step to better understand the trade in small shark fins on a species‐specific basis and highlight the need for market surveys and increased inspection of this fin category at border control check points for CITES‐listed species. We assessed the species composition of the small low‐value shark fins from the Hong Kong retail markets, using DNA mini‐barcoding protocols. A total of 475 samples were randomly collected and identified, reveling 29 different species. Around third of the species found are threatened with extinction and around 21% of the samples were from four species listed on the Convention on International Trade in Endangered Species (CITES). Our results represent the first step to better understand the trade ins mall shark fins on a species‐specific basis and highlight the need for increased inspection of this fin category at border control check‐points for CITES‐listed species.
... This dhow was consistently blamed for the drastic decline of shark populations in the area(Table 15.4). Sharks caught during this operation were either sold in Jeddah or transported to the Dubai fish market, which serves as major hub in the shark fin trade(Rose 1996;Jabado et al. 2015). ...
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.
... Higher availability of this species is needed to satisfy its increased demand since other sources of supply like aqua farming has not been in vogue for this species. This indicates possibilities of species substitution and misrepresentation using morphologically similar exotic, non-invasive, protected and low valued species, since seafood mislabelling is a global and significant issue in the present scenario [5][6][7][8][9][10] . In Kerala (S. ...
Article
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Species substitution is a case of fraud practised by the fish dealers for acquiring additional profit. During a fishery survey in the local markets of Kerala state (South India), some 'alien' fishes were encountered which were traded along with Parastromateus niger as 'black pomfrets'. Samples of these two groups were collected for morphological and molecular characterization (viz. COI gene). COI sequences of P. niger corroborated with the same in NCBI while morphological and molecular characters of 'alien' fishes corroborated with an exotic fish Piaractus brachypomus. Molecular analysis carried out using additional COI sequences of 'pomfret' and 'piranha' fishes acquired from NCBI confirmed the speciation of 'alien fishes' as P. brachypomus. This study reports the illegal trade of P. brachypomus as a species substituent for P. niger in Kerala and recommends the enforcement of strict laws for preventing food frauds as it could bring up serious economic breakdowns in fisheries sector.
... Australia, yet most of the sharks are discarded and the liver oil is unutilised [21]. Historically, the discarded WSLO was used for to proof wooden boats [22], but now these applications are no longer required as modern boats are fibreglass. The excess WSLO derived from these discarded shark livers in the fishing industry could instead be processed to obtain valuable products like biodiesel, squalene, and omega-3 PUFAs -including EPA and DHA. ...
Technical Report
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Biodiesel is a renewable alternative to “petro-diesel”. There is an established conventional production technology based on refined vegetable oils. However, this is always more expensive than petroleum-based diesel, mainly due to the feedstock cost, and the biodiesel market is based on subsidies. Use of a cheap non-edible feedstock, such as waste shark liver oil (WSLO), would reduce the biodiesel production cost and make the process more economically viable. In this study, production of fatty acid methyl ester (FAME) from WSLO using both acid (H2SO4) and base (NaOH) catalysts were investigated using a Design of Experiments approach (response surface methodology). Due to the high levels of FFA (free fatty acids) homogeneous alkali-catalysed transesterification of WSLO was less effective than the acid-catalysed process, resulting in WSLO to FAME conversion of 12% after 60 min, with maximum FAME conversion of about 40% after 15 min. Acid-catalysed WSLO transesterification achieved 99% FAME conversion at 10.3 M ratio of methanol to WSLO, 6.5 h reaction time, 60 °C temperature, and 5.9 wt % of H2SO4 catalyst.
... Shark fin product, including from scalloped hammerhead are very popular in Hong Kong [20], where trade regulations for endangered species and effective regulations are promoted [16,20,21]. The population structure of S. lewini, which is important for fisheries stock management, has been widely investigated in different coastal areas and ocean basins on a global and regional scale [17-19, 22, 23]. ...
Preprint
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The scalloped hammerhead shark Sphyrna lewini is an endangered species which expected to population declined worldwide including in Indonesia due to overexploited. However, there is a lack of information regarding recent population structure to promote proper management and conservation status in Indonesia. This study aimed to investigate the genetic diversity, population structure and connectivity of S. lewini population in Indonesia from three major sharks landing sites in Aceh (n= 41), Balikpapan (n= 30), Lombok (n= 29), and additional sequences retrieved from West Papua (n= 14) and Western Indian Ocean population (n= 65). Analyses of mitochondrial CO1 gene successfully identified a total of 179 sequences of S. lewini with an average 594 bp nucleotide with 40 polymorphic loci in 4 haplotypes for Indonesian population and 8 haplotypes for Western Indian Ocean. The overall values of genetic diversity in Indonesia was high (Hd= 0.7171; π= 0.0126), with the highest was in Aceh (Hd= 0.6683; π= 0.0198), and the lowest was in Papua (Hd= 0.1429; π= 0.0005), while in Western Indian Ocean the overall value was fairly low (Hd= 0.2322; π= 0.0010). The AMOVA and FST revealed three significant population subdivisions in Indonesia (FST= 0.4415; p < 0.001) with separated population for Aceh and West Papua, and a mixing population between Balikpapan and Lombok (FST= 0.044; p = 0.089), whereas relatively no significant differentiation within population in Western Indian Ocean (FST= -0.0131; p = 0.6011), and significant different level showed by Indonesian population compared with Western Indian Ocean population (FST= 0.7403; p < 0.001). The construction of haplotype network exhibited evidence of gene flow and haplotype sharing between populations. This result indicated a complex and limited connectivity population of S. lewini in Indonesia, and between Western Indian Ocean in regional scale which need co-management action across region.
... Therefore, any management suggestion, based on information from landings, should be seen with caution, especially if it proposes long-term measures or measures of large geographic coverage [3]. The difficulty in identifying landed shark species is being minimized by increasingly lower costs of molecular genetic techniques (for example, DNA barcoding) in global fisheries [43][44][45], therefore becoming an alternative to aid the identification and conservation of sharks in developing countries [46]. Affordable molecular tools may help refine data on shark catches, especially when a first ethnobiological approach is not conclusive. ...
Article
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Background: Accessing folk knowledge from small-scale fishers is an affordable and reliable approach to understand the dynamic and diversity of shark species worldwide, especially of those eventually caught. In this context, ethnotaxonomy (folk identification and classification) may represent an alternative to support sharks fisheries management, especially in data-poor places. This study aimed to investigate fishing and ethnotaxonomy of the main shark species caught by small-scale fisheries from the coastal waters of the Brazilian Northeast. Methods: Semi-structured and structured interviews were conducted with fishers targeting general aspects of fishing activities and specific topics regarding ethnotaxonomy, capture, and commercialization of sharks. For species identification, an ethnobiological systematic perspective was used to analyze the folk nomenclature and classification criteria. Non-parametric statistical tests were used to verify associations between species caught, fishing gear, and harvest period. Results: Fishers mentioned 73 binomial names, 21 main folk species, and eight synonymies. Some species belonging to the same scientific genus are often named and grouped by the same folk name, with no distinction between species by fishers. Sharks are most landed as bycatch and correspond to less than 5% of the total commercial fisheries in the communities, with socioeconomic value for subsistence consumption and local commercialization. Sharks were said to be mainly caught with hand line and surface long line during the rainy season, while gillnet captures were associated to the dry season. At least three of the species most mentioned by fishers are currently classified as vulnerable and endangered worldwide. Conclusions: Even though landed sharks account for a small proportion of the fishing catches, their biological and life history features place sharks among the most vulnerable organisms globally. Such an ethnobiological approach towards shark identification may contribute to generate basic information on species caught, their frequency in the landings, and how different species belonging to the same genus can be landed and sold together. This type of information can generate subsidies to the development of conservation and management plans for these fishing resources, where knowledge is scarce.
... 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). ...
Article
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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.
... Sharks are exploited primarily for their fins, meat, cartilage, liver oil and skin (Clarke, 2004), whereas rays are targeted for their meat, skin, gill rakers and livers. Most shark catch takes place in response to demand for the animals' fins, which command high prices (Jabado et al., 2015). Shark fin soup is a delicacy in many Asian countries-predominantly China-and in many other countries (Clarke et al., 2007). ...
Article
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This article looks into the shark and ray product collecting data from the biggest processing centers either for export of for meeting the domestic products in Bangladesh. This documents different type of products made and their end consumers as a part of a value chain study. This unveils an existing and emerging market for these products and identifies Bangladesh as a big exporter, hence recommends urgent conservation measures.
... Although there are more than 500 shark species worldwide, research has indicated that the fins of fewer than 50 shark species are considered commercially important 3 and recent studies in Hong Kong, SAR; Indonesia; Taiwan, Province of China and the United Arab Emirates have also shown that the species composition of the fin trade is dominated by fewer than 20 of the large-bodied carcharhinid and lamnid sharks, 4,5,6,7,8 many of which can be identified through the use of this guide. ...
Technical Report
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Identifying Shark Fins was created to help enforcement personnel to provisionally identify the dried and wet fins of commercially traded CITES listed shark species based on morphological characteristics of their most distinctive fins in their commonly traded form (frozen and/or dried and unprocessed) at the first point of trade. A preliminary visual identification will establish reasonable or probable cause in enforcement settings so that expert opinion can be sought or genetic testing can confirm field identification, aiding governments in successfully implementing and enforcing the CITES shark listings and promoting legal, sustainable trade
... Tissue samples were collected by fisheries observers and landing inspectors in Colombia and Ecuador from dead animals captured in longline fisheries. Additionally, whole specimens of sharks were transported overland by truck from the Oman fishery and were sampled as described in Jabado et al. [22]. Tissue samples were stored in 20% DMSO or 95% ethanol until DNA extraction was performed. ...
Article
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Microsatellites are useful in studies of population genetics, sibship, and parentage. Here, we screened for microsatellites from multiple elasmobranch genomic libraries using an enrichment protocol followed by sequencing on an Illumina platform. We concurrently screened five and then nine genomes and describe the number of potential loci from each respective round of sequencing. To validate the efficacy of the protocol, we developed and tested primers for the pelagic thresher shark, Alopias pelagicus. The method described here is a cost-effective protocol to increase the pool of potential useful loci and allows the concurrent screening of multiple libraries.
... Globally, the illegal trade in wildlife has recently reached unprecedented levels, estimated to be worth USD20 billion a year (CITES 2015). The surge in illegal trade has been documented in the West Asia region, with countries such as Jordan, Syria, the United Arab Emirates (UAE) and Yemen serving as transit hubs for smugglers from and to African and Asian countries (Jabado et al. 2015;Abido 2010). ...
Chapter
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In this assessment, the UNEP Secretariat and the authorsprovide an objective evaluation and analysis designed tosupport environmental decision making. Expert judgmentis applied to existing knowledge to provide scientificallycredible answers to policy-relevant questions. Environmental governance is the mechanism through which peace and resilience can be realized in West Asia. Good governance implies that issues such as conflict resolution, food, water and energy are examined in a holistic framework. Economic, social and environmental spheres must be integrated into a multi-sectoral policy design within the goals of sustainable development. Sustainable growth in the economies of West Asia will enable progress on food security, sustainable water sources, reduced vulnerability to natural and man-made disasters, reduced risks of climate change, permanent energy solutions and conservation of natural resources. The outlook calls for concerted efforts by governments, civil society and the private sector in West Asia to address environmental challenges in the region. (Source http://web.unep.org/geo/assessments/regional-assessments/regional-assessment-west-asia)
... Fishers operate 2 types of boats: small fiberglass dories ('tarad') and traditional wooden dhows ('lansh') with the primary fishing gear including drift nets, gill nets, hand lines, traps, longlines, and trolls (Grandcourt 2012, Jabado et al. 2015a. During a comprehensive fishery-dependent study of elasmobranchs in the UAE between 2010 and 2012 (Jabado et al. 2015b), only 1 sawfish (green sawfish) specimen was encountered at the Al Jubail landing site in Sharjah (R. Jabado unpubl. data). ...
Article
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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.
... (bull and shortfin mako). Skewed species composition is concordant with fin exports from Indonesia, United Arab Emirates, and Taiwan, which are important suppliers of HK, albeit each with its own unique set of dominant species (Jabado et al. 2015;Sembiring et al. 2015;Chuang et al. 2016). It is also concordant with the 1999-2001 HK trade (Clarke et al. 2006a(Clarke et al. , 2006b. ...
Article
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The shark fin trade is a major driver of shark exploitation in fisheries all over the world, most of which are not managed on a species-specific basis. Species-specific trade information highlights taxa of particular concern and can be used to assess the efficacy of management measures and anticipate emerging threats. The species composition of the Hong Kong Special Administrative Region of China, one of the world's largest fin trading hubs, was partially assessed in 1999–2001. We randomly selected and genetically identified fin trimmings (n = 4,800), produced during fin processing, from the retail market of Hong Kong in 2014–2015 to assess contemporary species composition of the fin trade. We used nonparametric species estimators to determine that at least 76 species of sharks, batoids, and chimaeras supplied the fin trade and a Bayesian model to determine their relative proportion in the market. The diversity of traded species suggests species substitution could mask depletion of vulnerable species; one-third of identified species face serious risk of extinction. The Bayesian model suggested that 8 species each comprised >1% of the fin trimmings (34.1-64.2% for blue [Prionace glauca]; 0.2-1.2% for bull [Carcharhinus leucas] and shortfin mako [Isurus oxyrinchus]); thus, trade was skewed to a few globally distributed species. Several other coastal sharks, batoids, and chimaeras are in the trade but poorly managed. Fewer than 10 of the species we modeled have sustainably managed fisheries anywhere in their range, including the most common species in trade, the blue shark. Our study and approach serve as a baseline to track changes in composition of species in the fin trade over time to better understand patterns of exploitation and assess the effects of emerging management actions for these animals.
... Shark fin product, including from scalloped hammerhead are very popular in Hong Kong [20], where trade regulations for endangered species and effective regulations are promoted [16,20,21]. The population structure of S. lewini, which is important for fisheries stock management, has been widely investigated in different coastal areas and ocean basins on a global and regional scale [17-19, 22, 23]. ...
Article
Full-text available
Scalloped Hammerhead shark (Sphyrna lewini) is an endangered species which its populations have been declining globally including in Indonesia, the world's top shark fishing country. However, there is a lack of information on the recent population structure of this species to promote proper management and its conservation status. This study aimed to investigate the genetic diversity, population structure, and connectivity of the S. lewini population, in three major shark landing sites: Aceh (n = 41), Balikpapan (n = 30), and Lombok (n = 29). Meanwhile, additional sequences were retrieved from West Papua (n = 14) and the Western Indian Ocean (n = 65) populations. From the analyses of the mitochondrial CO1 gene, a total of 179 sequences of S. lewini, with an average size of 594 bp, and 40 polymorphic loci in four and eight haplotypes for the Indonesian population and the Western Indian Ocean population were identified. The overall values of genetic diversity were high (h = 0.717; π = 0.013), with the highest values recorded in Aceh (h = 0.668; π = 0.002) and the lowest in Papua (h = 0.143; π = 0.000). On the contrary, the overall value was fairly low in the Western Indian Ocean (h = 0.232; π = 0.001). Furthermore, AMOVA and F ST showed three significant subdivisions in Indonesia (F ST = 0.442; P < 0.001), with separated populations for Aceh and West Papua, and mixed between Balikpapan and Lombok (F ST = 0.044; P = 0.091). In contrast, genetic homogeneity was observed within the population of the Western Indian Ocean (F ST =-0.013; P = 0.612). The establishment of a haplotype network provided evidence of a significantly different population and a limited genetic distribution between the Indonesian and the Western Indian Ocean populations (F ST = 0.740; P < 0.001). This study showed the presence of a complex population of S. lewini with limited connectivity only in Indonesia separated from the Western Indian Ocean and requiring specific management measures based on the population structure at the regional level.
... First, it keeps the focus squarely on human beings' wants and needs, and locates the potential loss in a failure to meet them, now or in the future. But this seems perverse, since it is precisely humanity's efforts to satisfy our wants and needs that are driving global biodiversity loss (Jabado et al., 2015). Preventing mass extinction would necessarily involve reining in people's self-interested economic activities (Mushet et al., 2014;Pidgeon et al., 2014)-as well as limiting the overproduction of human selves, each of whom inevitably places significant demands on the same limited resources needed by other organisms (Cincotta and Gorenflo, 2011;Mora and Sale, 2011). ...
Article
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If we want a whole Earth, Nature Needs Half: a response to Büscher et al. - Philip Cafaro, Tom Butler, Eileen Crist, Paul Cryer, Eric Dinerstein, Helen Kopnina, Reed Noss, John Piccolo, Bron Taylor, Carly Vynne, Haydn Washington
... At many sites sampled around the world, smaller-sized species are predominantly landed, as many of the larger-bodied shark species have been overfished [47][48][49][50]. Similarly, on peninsular India, shark stocks have declined over the past decade with smaller, faster-growing shark species displacing larger, slower-growing species [5,11,[51][52][53][54]. ...
Article
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Detailed information on shark and ray fisheries in the Andaman and Nicobar Islands, India are limited, including information on the diversity and biological characteristics of these species. We carried out fish landing surveys in South Andamans from January 2017 to May 2018, a comprehensive and cost-effective way to fill this data gap. We sampled 5,742 individuals representing 57 shark and ray species landed from six types of fishing gears. Of the 36 species of sharks and 21 species of rays landed, six species of sharks (Loxodon macrorhinus, Carcharhinus amblyrhynchos, Sphyrna lewini, C. albimarginatus, C. brevipinna, and Paragaleus randalli) comprised 83.35% of shark landings, while three species of rays (Pateobatis jenkinsii, Himantura leoparda and H. tutul) comprised 48.82% of ray landings, suggesting a species dominance in the catch or fishing region. We provide insights into the biology of species with extensions in maximum size for seven shark species. Additionally, we document an increase in the known ray diversity for the islands and for India with three previously unreported ray species. We found that amongst sharks, mature individuals of small-bodied species (63.48% males of total landings of species less than 1.5 m total length when mature) and immature individuals of larger species (84.79% males of total landings of species larger than 1.5 m total length when mature) were mostly landed; whereas for rays, mature individuals were predominantly landed (80.71% males of total landings) likely reflecting differences in habitat preferences along life-history stages across species and fishing gear. The largest size range in sharks was recorded in landings from pelagic longlines and gillnets. Further, the study emphasizes the overlap between critical habitats and fishing grounds, where immature sharks and gravid females were landed in large quantities which might be unsustainable in the long-term. Landings were female-biased in C. amblyrhynchos, S. lewini and P. jenkinsii, and male-biased in L. macrorhinus and H. leoparda, indicating either spatio-temporal or gear-specific sexual segregation in these species. Understanding seasonal and biological variability in the shark and ray landings over a longer study period across different fisheries will inform future conservation and fishery management measures for these species in the Andaman and Nicobar Islands.
... Their importance is partly due to the finning trade, which displays high commercial value (CARDEÑOSA et al., 2018). However, catching sharks only for their fins is a waste, as medium-sized sharks provide about 3% fins, 35% fillet, 13% liver rich in vitamins A and D, 9% skin, that can be used for making leather goods, and 40% waste that can be processed into animal feed meal (SZPILMAN, 2004;JABADO et al., 2015;TRAN, 2019). ...
Chapter
The dragonflies and damselflies (Odonata) are predatory insects that need water to reproduce. The males, sexually active, seek to live near to aquatic environments, and females visit the water, usually for copulation (mating) and laying (egg release). Biological collections are important sources of information. So that collections can, for example, effectively contribute to the construction and updating of the lists of Threatened Species, the specimens deposited therein must be identified at the species level and their data organized in a digital repository of records. This work aims to analyze the information available in the repository of records of the Reserva Natural Vale (RNV) about the Order Odonata. We found 200 specimens of Odonata, of which 18 (9%) are Aeshnidae, seven (3.5%) are Calopterygidae, 15 (7.5%) are Coenagrionidae, one (0.5%) are Dicteriadidae, 129 (64,5%) are Libellulidae, four (2%) are Heteragrionidae and 26 are (13%) specimens without any identification. Considering that 45 (21%) of the species registered in Espírito Santo (Brazil) do not have information about the locality of occurrence, identifying all the specimens and performing a biological survey for Odonata in the RNV may contribute significantly to the knowledge about this group of insects and to the analysis of the risk of extinction, as well as to the conservation of the species that inhabit there.
... Their importance is partly due to the finning trade, which displays high commercial value(CARDEÑOSA et al., 2018). However, catching sharks only for their fins is a waste, as medium-sized sharks provide about 3% fins, 35% fillet, 13% liver rich in vitamins A and D, 9% skin, that can be used for making leather goods, and 40% waste that can be processed into animal feed meal(SZPILMAN, 2004;JABADO et al., 2015;TRAN, 2019). ...
Chapter
Elasmobranchs are an ancient and diverse group of animals that inhabit aquatic ecosystems widely distributed around the globe. Due to late maturation and the production of few offspring, these organisms are currently among the most endangered species of all vertebrates. Overexploitation through predatory fishing and habitat degradation caused by anthropic activities are among the main threats to this group. In addition, a high number of species lacking information to assess their actual conservation status is noted. One of the obstacles to the conservation of this group is the incorrect identification of individuals caught during fishing activities and the lack of further studies that associate fishing activities to genetic diversity. In this regard, the use of molecular tools has shown promise, as they serve as instruments in the development of elasmobranch conservation plans and legislation. In this context, this review aims to show genetic studies on the Amazonian coast that can help in better understanding the stocks of the region and their dynamics in relation to fishing, discuss the main causes of threat to elasmobranchs as well as the use of molecular tools for purposes conservation, with emphasis on examples of species that inhabit the region of the Amazon Coast.
... Species of Sphyrnidae family are of the most caught sharks worldwide, and a large percentage of the fins sold in Asian markets come from this family [3,21,28,29] . Given their importance, identification protocols using molecular techniques have been implemented for sphyrnid species and have primarily consisted of DNA barcoding and multiplex PCR [3], [19], [21,27,[29][30][31][32][33][34][35][36][37] . In fact, species-specific primers and a five-primer multiplex PCR have been developed and extensively tested worldwide for S. lewini, Sphyrna mokarran, and S. zygaena [3] . ...
Article
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The demand for shark fins in Asiatic markets has resulted in excessive increases in shark catches, even for species that may be under protection or subject to management. As such, it has been necessary to develop and promote monitoring efforts for exploited species and taxonomic groups in order to improve fishing management strategies for elasmobranchs. Identifying species from landings is one of many fishing management problems because landed organisms have usually already been processed and are therefore incomplete, which makes identification problematic, impedes the generation of proper species records, and leads to poor fishery assessments. Tools that can correctly identify species, such as various molecular techniques, have become essential for accurate fishery assessments. In this study, 30 hammerhead trunks from artisanal fisheries from the southern portion of the Gulf of California were identified using multiplex PCR (17 Sphyrna lewini and 13 Sphyrna zygaena). The total fee to identify each trunk with this technique was ~ $3.80 and the procedure required 2 to 5 days. When compared with other widely-used methods, such as PCR-RFLP or barcoding, multiplex PCR is fast, efficient, low-cost, and easy to implement in a laboratory.
... Mitochondrial cytochrome c oxidase I subunit gene (COI) are useful for specimen identification and species confirmation in many cases, generating molecular sequence data from fresh, degraded, processed or cooked material Deepak & Harikrishnan, 2016;Sameera et al., 2019). Hitherto, there are numerous reports by Wong & Hanner, 2008;Hanner et al., 2011;Filonzi, Chiesa, Vaghi, & Marzano, 2010;Jabado et al., 2015;Lockely & Bardsley, 2000;Gil, 2007;Ardura, Ana, Moreira, & Garcia-Vazquez, 2010;Xiong et al., 2016;Willette et al., 2017;Stern, Nallar, Rathod, & Crandall, 2017;Spencer & Bruno, 2019;Deepak et al., 2019 andSameera et al., 2019 regarding the utility of DNA barcoding in seafood authentication. Hence, this study also suggests the mandatory implementation of molecular techniques like DNA barcoding in Indian markets so that malpractices like food fraud in the form of species substitution/misrepresentation and unregulated fishing could be rectified. ...
Article
Trade flow of fisheries sector is very complex with several intermediaries and it is difficult to trace back the origin of a seafood commodity. Thus, traceability limitations could cause safety and quality issues in the final product delivered to the consumers. Decreased monitoring may also increase the possibilities of illegal, unre-ported and unregulated fishing practises. In global fisheries sector, a proper species identification system for identifying and preventing commercial frauds like species misrepresentation and illegal trade is mandatory. DNA analysis is a promising technique for food authentication as it provides increased specificity, sensitivity and reliable performance for accurate specimen identification and species confirmation. Mitochondrial cytochrome c oxidase subunit I gene (mtCOI) fragments represent one of the robust genetic marker for identification of specimens up to species level. It is a stable genetic marker which could be amplified from fresh, degraded, processed or cooked materials. India is having very limited regulations for preventing improper labelling of seafood items and ensuring authentication for traded fish and fishery products. This study focuses on the applicability of DNA barcodes over fish and fishery products traded at different sectors like local markets, supermarkets , restaurants etc. Samples collected from different stations of Ernakulam district (Kerala, S. India), were subjected to molecular analysis and COI sequences were developed. Among the 62 samples, 34 samples were identified as species substituents and the substitution rate was accounted up to 54.84%. In addition, trade of certain exotic/invasive and illegally cultured species were also confirmed. This study discusses the applicability of DNA barcoding in fisheries sector for preventing food fraud and suggests its implementation as a systematic regulatory programme conducted by governmental agencies for fishery stocks authentication.
... Sharks were regularly encountered on Sudanese reefs and were very sparse in Saudi Arabia. These observations corroborate reports in previous studies for both regions (Hussey et al. 2013;Clarke et al. 2013;Spaet and Berumen 2015) and echo warnings of elasmobranch overexploitation in Saudi Arabia, despite a 2008 royal decree prohibiting all shark fishing activities in the country (Jabado et al. 2015;Spaet et al. 2016). Strict enforcement of this law is urgently needed to avoid ecosystem-wide repercussions of shark removal (Stevens et al. 2000;Baum and Worm 2009;Ferretti et al. 2010;Ruppert et al. 2013). ...
Article
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In order to assess human impacts and develop rational restoration goals for corals reefs, baseline estimates of fish communities are required. In Saudi Arabian waters of the Red Sea, widespread unregulated fishing is thought to have been ongoing for decades, but there is little direct evidence of the impact on reef communities. To contextualize this human influence, reef-associated fish assemblages on offshore reefs in Saudi Arabia and Sudan in the central Red Sea were investigated. These reefs have comparable benthic environments, experience similar oceanographic influences, and are separated by less than 300 km, offering an ideal comparison for identifying potential anthropogenic impacts such as fishing pressure. This is the first study to assess reef fish biomass in both these regions, providing important baselines estimates. We found that biomass of top predators on offshore Sudanese reefs was on average almost three times that measured on comparable reefs in Saudi Arabia. Biomass values from some of the most remote reefs surveyed in Sudan’s far southern region even approach those previously reported in the Northwestern Hawaiian Islands, northern Line Islands, Pitcairn Islands, and other isolated Pacific islands and atolls. The findings suggest that fishing pressure has significantly altered the fish community structure of Saudi Arabian Red Sea reefs, most conspicuously in the form of top predator removal. The results point towards the urgent need for enhanced regulation and enforcement of fishing practices in Saudi Arabia, while making a strong case for protection in the form of no-take marine protected areas to maintain preservation of the relatively intact southern Sudanese Red Sea.
... Jabado et al. 2015). Three species of thresher shark, Bigeye Thresher, Pelagic Thresher, and Common Thresher (A. vulpinus), collectively accounted for 2-3% in 1991-2001 and 0.5% in 2014, of the fins imported in Hong Kong(Clarke et al. 2006a, Fields et al. 2018. ...
... The species is used for its meat, fins, liver oil, and skin (Compagno 2001, Goldman 2005, Jabado et al. 2015. Three species of thresher shark, Common Thresher, Bigeye Thresher, and Pelagic Thresher, collectively accounted for 2-3% in 1991-2001 and 0.5% in 2014, of the fin imported in Hong Kong (Clarke et al. 2006a, Fields et al. 2018). ...
... In the Arabian Seas region, surveys of fish markets and landings sites have revealed this species to be a major part of elasmobranch landings, often as bycatch in gillnet fisheries (Henderson et al. 2007, Moore et al. 2012, Moore and Peirce 2013, Jabado et al. 2015, Spaet and Berumen 2015. The high level of exploitation on its habitat in the region is of concern. ...
... The differentiation of species at the molecular level was initially proposed by Hebert et al. (2003) using the mitochondrial gene Cytochrome c oxidase subunit 1 (COI) as an effective 'barcode' capable of identifying the species, and subsequently was critically reviewed by Krishna & Francis (2012). DNA barcoding has already been applied to provide forensic evidence of the various species (Jabado et al., 2015), Indonesia (Sembiring et al., 2015), and in some regions of Brazil (Rodrigues-Filho et al., 2009;Ramos et al., 2017;Staffen et al., 2017;Almer on-Souza et al., 2018;Bunholi et al., 2018;Feitosa et al., 2018;Calegari, Reis & Alho, 2019;Bernardo et al., 2020). ...
Article
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• Elasmobranchs are apex predators that play a crucial role in marine ecosystems by regulating the dynamics of food webs, as well as connecting different trophic levels across habitats. • The large-scale removal of elasmobranchs impacts the energy transfer in trophic interactions. The pressure of unsustainable fisheries is considerable, as most elasmobranchs have reproductive strategies that render them unable to recover their demographic status after depletion. • In Brazil, elasmobranchs are broadly commercialized under the generalist common name of ‘cação’ (namely, shark meat). This allows threatened species to be commercialized and makes the tracking of different species difficult. • DNA barcoding of the Cytochrome c oxidase subunit 1 (COI) gene was applied to identify the different species sold as ‘cação’ along the coastline of Brazil. Fifty-seven samples from 33 cities in 15 coastal states of Brazil were purchased and analysed. • Bioinformatic analyses revealed the presence of 17 species that were sold as ‘cação’. Among them, Prionace glauca (blue shark) was the most abundant. Other species, listed as Endangered under the IUCN Red List of Threatened Species, were also uncovered as being in the shark meat trade, such as Sphyrna lewini (scalloped hammerhead), Isurus paucus (longfin mako shark), and Squatina guggenheim (angular angel shark). • These findings have reinforced the necessity to correctly label the commercialized species. Public actions towards species-specific management plans must be applied, as well as monitoring the supervised allied educational programmes.
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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
Shark fin has long been one of the most highly demanded 'luxury seafood' in the Chinese market. From the latest available data (1998–2013), 130 countries/territories around the world were recorded as exporting shark fin to Hong Kong. Spain, Taiwan, Indonesia, UAE, Singapore and Japan made up over 50% of all of Hong Kong's shark fin imports. Comparison of Hong Kong's import data with the exporting countries/territories' FAO declarations indicates that some countries/territories are potentially consistently underreporting shark fin exports. Since 2009 Vietnam had overtaken China as the most important destination of Hong Kong's shark fin re-exports, a change that warrants further investigation. Ocean transportation was also identified as the most important transportation mode for shark fin imports into and re-exports from Hong Kong. Given the importance of Hong Kong and based on findings from this study, suggestions are made for the Hong Kong Government to tighten controls to reduce illegal trades, and eliminate loopholes so that a more comprehensive statistical representation of the shark fin trade may be captured for future analysis.
Article
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
Thesis
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Public awareness of nature and environmental issues has grown in the last decades and zoos have successfully followed suit by re-branding themselves as key representatives for conservation. However, considering the fast rate of environmental degradation, in the near future, zoos may become the only place left for wildlife. Some scholars argue that we have entered a new epoch titled the “Anthropocene” that postulates the idea that untouched pristine nature is almost nowhere to be found.1 Many scientists and scholars argue that it is time that we embraced this environmental situation and anticipated the change. 2 Clearly, the impact of urbanization is reaching into the wild, so how can we design for animals in our artificializing world? Using the Manoa School method that argues that every future includes these four, generic, alternatives: growth, discipline, collapse, and transformation3, this dissertation explores possible future animal archetypes by considering multiple possibilities of post zoo design.
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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.
Preprint
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The scientific literature on the diversity and biological characteristics of sharks and rays from the Andaman and Nicobar Archipelago fishing grounds is scarce and compromised by species misidentifications. We carried out systematic fish landing surveys in South Andamans from January 2017 to May 2018, a comprehensive and cost-effective way to fill this data gap. We sampled 5,742 individuals representing 57 shark and ray species. Of the 36 species of sharks and 21 species of rays landed, six species of sharks - Loxodon macrorhinus, Carcharhinus amblyrhynchos, Sphyrna lewini, Carcharhinus albimarginatus, Carcharhinus brevipinna and Paragaelus randalli dominated landings and comprised 83.35 % of shark landings, while three species of rays were most abundant - Pateobatis jenkinsii, Himantura leoparda and H. tutul , and comprised 48.82 % of ray landings. We report size extensions for seven shark species as well as three previously unreported ray species, increasing the known diversity for the islands and for India. For sharks, mature individuals of small-bodied species (63.48 % males of total landings of species less than 1.5 m total length) and immature individuals of larger species (84.79 % males of total landings of species larger than 1.5 m total length) were mostly landed; whereas for rays, mature individuals were predominantly landed (80.71 % males of total landings) likely reflecting differences in fishing patterns as well as habitat preferences and life history stages across species. Further, juvenile sharks and gravid females were landed in large quantities which might be unsustainable in the long-term. Landings were female-biased in C. amblyrhynchos, S. lewini and P. jenkinsii , and male-biased in L. macrorhinus and H. leoparda , indicating either spatio-temporal or gear specific sexual segregation in these species. Understanding these nuances - the composition and biology of sharks and rays landed in different fisheries seasonally will inform future conservation and fishery management measures for these species in the Andaman and Nicobar Islands.
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The oceanic whitetip shark (Carcharhinus longimanus) was once considered one of the most abundant and ubiquitous pelagic shark species in tropical seas globally. However, over the last several decades, the oceanic whitetip has experienced substantial population declines throughout its range due to fishing pressure and utilization in the international fin trade. In recent years, a significant amount of research has been undertaken on this species, revealing new information on life history, movements and behavior, and threats to the species. Additionally, a recent surge of protective measures has been implemented for the oceanic whitetip shark, both internationally and nationally. These include (but are not limited to) retention prohibition measures in every major tuna Regional Fishery Management Organization (RFMO), its listing in Appendix II of the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES), and its listing under the U.S. Endangered Species Act (ESA) as a threatened species. However, despite its global distribution and common occurrence in many commercial fisheries in tropical waters, little is still known regarding the oceanic whitetip shark’s biology and population status. Therefore, we summarize what is known on the biology and conservation of the oceanic whitetip shark, identify information gaps, and discuss future directions for recovery of this imperiled species.
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Biodiesel is a renewable alternative to “petro-diesel”. There is an established conventional production technology based on refined vegetable oils. However, this is always more expensive than petroleum-based diesel, mainly due to the feedstock cost, and the biodiesel market is based on subsidies. Use of a cheap non-edible feedstock, such as waste shark liver oil (WSLO), would reduce the biodiesel production cost and make the process more economically viable. In this study, production of fatty acid methyl ester (FAME) from WSLO using both acid (H2SO4) and base (NaOH) catalysts were investigated using a Design of Experiments approach (response surface methodology). Due to the high levels of FFA (free fatty acids) homogeneous alkali-catalysed transesterification of WSLO was less effective than the acid-catalysed process, resulting in WSLO to FAME conversion of 12% after 60 min, with maximum FAME conversion of about 40% after 15 min. Acid-catalysed WSLO transesterification achieved 99% FAME conversion at 10.3 M ratio of methanol to WSLO, 6.5 h reaction time, 60 °C temperature, and 5.9 wt % of H2SO4 catalyst.
Chapter
Global trade of seafood has increased in the last decade, leading to significant concerns associated with seafood fraud. Seafood fraud involves the intentional misrepresentation of fish or shellfish for the purpose of economic gain and includes acts such as species substitution, illegal transshipment, overtreatment/short weighting, and mislabeling country of origin or production method. These fraudulent acts have had economic, environmental, and public health consequences on a global level. DNA-based techniques for seafood authentication are utilized by regulatory agencies and can be employed as part of a food fraud risk mitigation plan. This chapter will focus specifically on the use of DNA-based methods for the detection of seafood species substitution. Various methods have been developed for DNA-based species identification of seafood, including polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), species-specific PCR, real-time PCR, Sanger sequencing, microarrays, and high-resolution melting (HRM). Emerging techniques for seafood authentication include droplet digital PCR, isothermal amplification, PCR-enzyme-linked immunosorbent assay (ELISA), and high-throughput or next-generation sequencing. Some of these DNA-based methods target specific species, such as real-time PCR and droplet digital PCR, while other methods allow for simultaneous differentiation of a wide range of fish species, including Sanger sequencing and high-throughput sequencing. This chapter will begin with an introduction on seafood fraud and species substitution, followed by an analysis of the main DNA-based authentication methods and emerging techniques for species identification.
Chapter
Seafood is an important source of protein worldwide. However, it is susceptible to a variety of fraudulent practices, including species substitution, illegal transshipment, and short-weighting. This chapter describes the global seafood industry and the ways in which it is vulnerable to fraud. Common categories of seafood fraud are discussed, along with the potential consequences of fraud. Data on seafood fraud incidences, including specific large-scale studies, are presented. Various analytical tools are evaluated for use in seafood fraud identification, and risk mitigation strategies are discussed to bridge communication and knowledge between the food industry, regulatory agencies, and consumers.
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.
Article
• All five species of sawfishes (family Pristidae) are amongst the most threatened marine fishes in the world, with steep population declines and local extinctions documented across their ranges. • Sawfishes have featured in Sri Lankan species checklists since 1889. However, landing records are extremely rare and little information is available on their status, diversity, and recent occurrences. • Interviews were conducted with 300 fishers and 10 fish traders. Only 39% of fishers (n = 118) could identify sawfishes, 37% had seen sawfishes (although half not since 1992), and only 10.7% had ever caught one. No respondents under 30 years could identify sawfishes. Older respondents (>50 years) were more likely to have caught sawfishes and reported seeing them frequently until 30 years ago, while younger respondents had only seen them at landing sites and, at most, once or twice in their life. Only 10 respondents had seen a sawfish in the last decade, suggesting that sawfishes were relatively abundant in the past but that populations have drastically declined. • Of the 32 respondents who had caught sawfishes, 30 reported declining numbers and attributed it to fishing pressure. These steep declines coincide with the time of increased fishing effort, the development of the aquaculture industry, and resulting degradation of coastal habitats in the 1980–1990s. • Overall, sawfishes had little cultural significance although fishers had specific names for the different species occurring here and rostra were sometimes donated to Catholic churches for ‘good luck’. Landed sawfishes were primarily sold for meat and traders appeared unaware of the high value of fins. • It is likely that sawfishes are now functionally extinct as a component of coastal ecosystems in Sri Lanka. Immediate action including species-specific legislation and critical habitat protection is urgently needed to provide remaining sawfishes and other sharks and rays with a fighting chance.
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The bull shark (Carcharhinus leucas Valenciennes, 1839) is a large, primarily coastally distributed shark famous for its ability to penetrate far into freshwater bodies in tropical, subtropical, and warm-temperate climates. It is a cosmopolitan species with a geographical range that includes the coastlines of all major ocean basins (Atlantic Ocean, Indian Ocean, Pacific Ocean). As a consequence, freshwater occurrences of C. leucas are possible everywhere inside its geographic range. Carcharhinus leucas is a fully euryhaline, amphidromous species and possibly the widest-ranging of all freshwater tolerating elasmobranchs. This species is found not only in river systems with sea access that are not interrupted by human impediments but in hypersaline lakes as well. Rivers and estuaries are believed to be important nursery grounds for C. leucas, as suggested by observations of pregnant females in estuaries and neonates with umbilical scars in rivers and river mouths. Due to the physical capability of this species to enter riverine systems, the documentation of its occurrence in fresh and brackish water is essential for future conservation plans, fishery inspections, and scientific studies that focus on the link between low salinity habitats, shark nurseries, and feeding areas. The author’s review of the available literature on C. leucas revealed the absence of a comprehensive overview of fresh and brackish water localities (rivers and associated lakes, estuaries) with C. leucas records. The purpose of this literature review is to provide a global list of rivers, river systems, lakes, estuaries, and lagoons with records and reports of this species, including a link to the used references as a base for regional, national, and international conservation strategies. Therefore, the objective of this work is to present lists of fresh and brackish water habitats with records of C. leucas as the result of an extensive literature review and analysis of databases. This survey also took into account estuaries and lagoons, regarding their function as important nursery grounds for C. leucas. The analysis of references included is not only from the scientific literature, but also includes semi-scientific references and the common press if reliable. The result of 415 global fresh and brackish water localities with evidence of C. leucas highlights the importance of these habitats for the reproduction of this species. Moreover, gaps in available distribution maps are critically discussed as well as interpretations and conclusions made regarding possible reasons for the distribution range of C. leucas, which can be interpreted as the result of geographic circumstances, but also as a result of the current state of knowledge about the distribution of this species. The results of the examination of available references were used to build a reliable and updated distribution map for C. leucas, which is also presented here.
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This checklist aims to reviews and summarize the results of the systematic researches on the Persian Gulf ichthyofauna that has been carried out for more than 200 years. Since the work of C. Niebuhr, a Danish biologist in the 18th century, the number of valid species has increased significantly and the systematic status of many of the species has changed, and reorganization and updating of the published information has become essential. Here we take the opportunity to provide a new and updated checklist of fishes of Persian Gulf based on literature and taxon occurrence data obtained from natural history and new fish collections. The total confirmed fish species of Persian Gulf comprise 744 species, 131 families, 445 genera and 27 orders. In the class Chondrichthyes, the most diverse family is Charcharhinidae with 23 species (41.89%), followed by Dasyatidae with 15 species (31.08%). Within the class Actinopterygii, Gobiidae with 65 species (9.70%), Carangidae with 45 species (6.27%), Serranidae with 25 species (3.73%), Apogonidae with 25 species (3.73%), Lutjanidae with 23 species (3.43%) and Blenniidae with 23 species (3.43%) are the most diverse families in the Persian Gulf.
Book
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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
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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
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1. Fishing spans all oceans and the impact on ocean predators such as sharks and rays is largely unknown. A lack of data and complicated jurisdictional issues present particular challenges for assessing and conserving high seas biodiversity. It is clear, however, that pelagic sharks and rays of the open ocean are subject to high and often unrestricted levels of mortality from bycatch and targeted fisheries for their meat and valuable fins. 2. These species exhibit a wide range of life-history characteristics, but many have relatively low productivity and consequently relatively high intrinsic vulnerability to over-exploitation. The IUCN}World Conservation Union Red List criteria were used to assess the global status of 21 oceanic pelagic shark and ray species. 3. Three-quarters (16) of these species are classified as Threatened or Near Threatened. Eleven species are globally threatened with higher risk of extinction: the giant devilray is Endangered, ten sharks are Vulnerable and a further five species are Near Threatened. Threat status depends on the interaction between the demographic resilience of the species and intensity of fisheries exploitation. 4. Most threatened species, like the shortfin mako shark, have low population increase rates and suffer high fishing mortality throughout their range. Species with a lower risk of extinction have either fast, resilient life histories (e.g. pelagic stingray) or are species with slow, less resilient life histories but subject to fisheries management (e.g. salmon shark). 5. Recommendations, including implementing and enforcing finning bans and catch limits, are made to guide effective conservation and management of these sharks and rays.
Technical Report
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European fleets are among the world’s leaders in fishing for sharks, reporting over 13% of global landings to the FAO in 2004. The most valuable parts of most sharks are their fins, which are a delicacy in Chinese cuisine. Shark meat is less profitable, which results in a strong economic incentive to cut off the fins and discard the carcass back into the sea, a practice called shark “finning”. In June 2003, the Council of the European Union adopted a Regulation on the removal of shark fins on-board vessels, which was intended to prevent the practice of shark finning within the European fleet (one of the world’s largest shark fishing entities). The European Commission reviewed the finning regulation in December 2005, stimulating significant debate in the European Parliament on its efficacy and whether the measures in force were fit for the purpose. An expert workshop, funded by the Lenfest Ocean Program, was convened in Brussels in October 2006 by the Shark Alliance to contribute towards shark fisheries management discussions in Europe. The purpose of the workshop was to describe and compare available data about shark fisheries, markets, trade and biology, and to develop science-based recommendations regarding precautionary and science-based conversion rates for shark products, particularly fin to carcass ratios or other methods that might be used to prevent the practice of shark finning. This document is the report of that workshop. http://eulasmo.org/blog/european-shark-fisheries/
Article
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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.
Technical Report
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Sharks and their relatives - the rays and chimaeras - are the diverse group of cartilaginous fishes (Class Chondrichthyes) that have evolved over 400 million years. ... ... ... This report serves as an introduction to the ecology, status and conservation of the sharks and their relatives for a general audience. It draws attention to their unique biology and makes the case for expanded political and financial investment in research, monitoring and precautionary management for all fisheries taking sharks, skates, rays and chimaeras as part of their catch. Shark fisheries cannot be managed sustainably, nor shark populations remain viable, in the absence of new conservation and management initiatives. http://www.iucnssg.org/uploads/5/4/1/2/54120303/camhi_et_al._1998.pdf
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Records of 11 elasmobranch species previously unreported from, or uncommon in, Omani waters are presented. Records new to Oman include Carcharhinus altimus, C. leiodon, Centrophorus isodon, Ctenacis fehlmanni, Himantura fai, Mobula eregoodootenke and Sphyrna zygaena, whereas noteworthy records of uncommon species include Himantura imbricata, Paragaleus randalii, Rhinobatos salalah and Taeniura meyeni – some of which are confirmed from the Gulf of Oman for the first time. These records bring to 57, the number of elasmobranch species confirmed in Omani waters.
Article
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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
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The future status of sharks is an issue of widespread conservation concern due to declines in many species in the face of high levels of exploitation to satisfy market demands for products, especially fins. Substantial declines in the large-bodied hammerhead sharks, Sphyrna lewini, S. mokarran and S. zygaena, even in regions where some management occurs, indicate that informed conservation measures are warranted for these circumglobally distributed species. Despite the importance of assessing shark catch and trade on a species-specific basis to detect potential overexploitation of individual species, achieving this goal for hammerheads has proven elusive due to difficulties in identification of their products. Here, we present the development and application of a diagnostic, streamlined, five-primer multiplex polymerase chain reaction assay utilizing species-specific primers based on nuclear ribosomal ITS2 for the three hammerhead species throughout their global distribution. Application of this assay to investigations of the fin market confirmed the presence of hammerhead fins in the international trade. A study of the world’s largest fin market in Hong Kong revealed a high concordance between specific Chinese-name trade categories and fins from these three species (“Bai Chun” with S. lewini, “Gui Chun” with S. zygaena and “Gu Pian” with S.␣mokarran), and clear species preferences. This concordance information allows the use of market records for monitoring species-specific trends in trade and exploitation rates. The assay is also proving useful for identification of shark body parts in U.S. fisheries law-enforcement activities. Screening of morphologically identified “ S. lewini” from globally distributed areas using this assay with subsequent whole ITS2 sequencing suggests a cryptic species closely related to S. lewini occurs off the SE USA coast.
Article
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Impacts of chronic overfishing are evident in population depletions worldwide, yet indirect ecosystem effects induced by predator removal from oceanic food webs remain unpredictable. As abundances of all 11 great sharks that consume other elasmobranchs (rays, skates, and small sharks) fell over the past 35 years, 12 of 14 of these prey species increased in coastal northwest Atlantic ecosystems. Effects of this community restructuring have cascaded downward from the cownose ray, whose enhanced predation on its bay scallop prey was sufficient to terminate a century-long scallop fishery. Analogous top-down effects may be a predictable consequence of eliminating entire functional groups of predators.
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