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The trade in sharks and their products in the United Arab Emirates
... Over the last few decades, conservation concerns have focused on the role of fins in driving unsustainable exploitation of sharks, with the spotlight largely focused on finning practises and strong demand from Asian markets [45,66,67]. However, recent research focus has increasingly shifted towards the role of other shark products, particularly meat, in driving shark trade [21,46,60,68]. This more nuanced understanding acknowledges the importance of cheap protein sources and desirable food choice, in many countries globally [16,60,69]. ...
... This more nuanced understanding acknowledges the importance of cheap protein sources and desirable food choice, in many countries globally [16,60,69]. We identify that, within Sri Lanka, meat is in strong demand, and reaffirm the importance of domestic demand for meat in driving shark fisheries and trade [10,46,68]. ...
... This study reasserted complexities in ascertaining compliance with species-specific policies [60,68,81]. Processing, including cutting and drying of sharks, throughout supply chains, combined with the taxonomic complexity of sharks, constrains accurate species identification. ...
Decades of unsustainable fishing have caused widespread declines in shark populations leading to calls for increased management and policy. To design successful measures, an understanding of the social context and drivers for trade is needed. This study uses a value chain approach in Sri Lanka, where shark landings have declined rapidly, to map shark trade actors, ascertain determinants of price of shark meat and determine wider social value of shark products. Data was collected over one year from surveys of sales events (n = 630), and semi-structured interviews (n = 24), at two sites on the south and west coasts. We identify a dynamic, flexible supply chain with a small number of specialised stakeholders that may alternate roles depending on factors such as supply of sharks. Sharks were the primary income source for most (71%, n = 17) and 25% (n = 6) reported no alternative income sources. Trade was dominated by dried shark meat in the domestic market, and demand shaped by its perceived nutritional benefits and taste. Identification of species was difficult, and shark meat was primarily sold as size categories, however, whether or not shark was sold as blue shark (Prionace glauca) significantly impacted price reportedly due to lower international demand for their fins. Stakeholders perceived substantial drops in shark landings and trade > 10 years ago. We show that, within Sri Lanka, shark products represent a nexus of two dramatically different markets: high-value fins for their export markets and low to medium-value meat important for domestic earnings. The presence of dried products reportedly increases resilience of shark trade to socio-ecological shocks. Disentangling the relative social importance of these products, through product-specific and species-specific data is vital for a move towards predictive management that is capable of robust outcomes.
... Surveys in Kuwait found that the Bull Shark made up 1.7-2.3% of elasmobranchs landed, but was much rarer in Qatar (0.05%) and absent in Bahrain (Moore et al. 2012, Moore andPierce 2013). In the United Arab Emirates (UAE), it makes up 1.3% of shark landings by number (Jabado et al. 2015), and in Iran, 2-3% of shark landings by number (T. Valinassab unpubl. ...
... data 2017). It is caught in Oman where it is not uncommon (Henderson and Reeve 2014) and it comprised 5% of sharks transported from Oman to the UAE by number (Jabado et al. 2015). It makes up less than 1% of catches by number in Pakistan with evidence suggesting declines of about 80% since the 1990s (M. ...
... Data available from India is from the Cochin Fish Harbour where this species represented 3.6% of shark landings by number in 1986-1987, but this number declined to 0.1% in 2006-2007(Akhilesh et al. 2011. Fisheries in the region have experienced increased demand for sharks since the 1970s due to the shark fin trade and as a result, effort is increasing in traditional shark fisheries in many areas (Henderson et al. 2007, Jabado et al. 2015. Simultaneously, there has been a significant increase in coastal fishing effort and power in some parts of the Arabian Seas region leading to a reduction in the number of shark catches. ...
... Shark skin (tanned and untanned) has a wide variety of uses. In the 1930s, tanned shark skin was traded in the US leather market (Rose, 1998) and more generally it is used for making leather products such as belts, purse, money bag, watchstraps, boots and shoes in at least the United States, Mexico, France, Spain, Indonesia, Japan, UAE and India (Clarke, 2004a;Dent & Clarke, 2015;Jabado et al., 2015;Muttaqin et al., 2019;Rose, 1996Rose, , 1998Tovar-Avila et al., 2020;Vannuccini, 1999). Untanned skin (referred to as 'shagreen') is used for making food products (e.g. ...
... Shark jaws and teeth are often considered by-products of commercial fisheries worldwide (Clarke, 2004a). Jaws are used for decorative purposes in UAE (Jabado et al., 2015) and teeth for making ...
... Shark flesh imports have been estimated at an aver- Other shark parts (e.g. cartilage, skin, liver and teeth) are also traded nationally and internationally but in considerably lower volumes (Dent & Clarke, 2015;Hasan et al., 2017;Jabado et al., 2015;Muttaqin et al., 2019;Tovar-Avila et al., 2020). The trade value of shark parts other than fins and flesh is comparably lower (Clarke, 2004a;Rose, 1996;Vannuccini, 1999). ...
Sharks and rays evolved 450 million years ago, during the Late Ordovician Period. However, during the modern Anthropocene, shark populations have declined at considerable rates, and recent global assessments indicate about one in three species is threatened with extinction. A notable reason for this elevated extinction risk is overfishing linked to increased demand for shark fins and other products. Here, we review multiple dimensions of consuming shark products, ranging from stock sustainability, product (mis)labelling and trade, the human health implications of consuming shark products, and illegal, unreported and unregulated fishing and slavery and labour abuses in the fishing industry. We conclude that traceability and increased transparency in seafood supply chains is essential to overcome obstacles to consumption of sustainable, ethical and healthy shark products. We also provide a decision tree outlining steps in consumer choice that would foster such consumption. Our aim is to provide a holistic view on issues concerning the consumption of shark products that will help policymakers, the public, management and law enforcement agencies to advocate for ecologically‐ and ethically sustainable consumption of shark products and thereby empower the general public to make informed decisions on which shark products they consume.
... Sampling was similar to the method described by Jabado et al. (2015), who conducted visits to the market twice a month. In total, six visits to the market were conducted, with each visit representing a sampling event consisting of the collection of 25 tissue samples, obtained from six vendors at the '17 de Diciembre' market. ...
... The commercial dynamic of the shark meat was investigated through observations in the market and informal conversations with fish inspectors and shark merchants. We asked questions to determine the origin of the samples, their economic value, and other questions about shark commerce (Jabado et al. 2015;Núñez and Wuest 2019). ...
This is the first study to determine the main shark species being sold in the ‘17 de Diciembre’ market, in Santo Domingo de Los Tsáchilas, Ecuador. A total of 150 samples were collected and molecularly identified through a multiplex polymerase chain reaction (PCR) with species-specific primers based on the ribosomal region ITS2. As a result, we found that the shark sales are made up by five main species. The pelagic thresher (Alopias pelagicus) was the most common species, followed by the silky shark (Carcharhinus falciformis), the scalloped hammerhead shark (Sphyrna lewini), the blue shark (Prionace glauca) and the shortfin mako shark (Isurus oxyrinchus). Of the analyzed samples, 93.24% (n = 138) correspond with species that are in one of the International Union for Conservation of Nature (IUCN) threat categories and Appendix II of Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The study highlights the need for this molecular tool to be implemented in strategic control points, as well as other measures that better ensure traceability.
... 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). ...
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.
... Lamniform sharks comprise substantial portions of the global shark fishery (Jabado et al., 2015), with shortfin mako sharks particularly prized for their high-quality meat and fins leading to concerns regarding their population viability and potential for rebuilding of stocks (Sims et al., 2021). Unfortunately, unscrupulous commercial fishers occasionally attempt to pass off protected white sharks as shortfin mako sharks in fish markets (Peddemors, personal communication). ...
The analysis of how biological shape changes across ontogeny can provide us with valuable information on how species adapt behaviorally, physiologically, and ecologically. The white shark Carcharodon carcharias is one of the largest and most widely distributed apex predators globally, yet an understanding of ontogenetic changes in body shape and relative scaling of length and weight measures is limited, especially in relation to foraging ecology. Through analysis of a suite of shape‐related metrics, we identified ontogenetic patterns of scaling throughout development. Isometric growth was exhibited for most metrics, failing to show a significant deviation from an isometric slope of 1.0 for length–length relationships, and 3.0 for weight–length relationships. The most notable difference from this trend was the negative allometric growth observed for the upper caudal‐fin lobe length, trunk length, and the mouth length. The surface area of the fins also presented a strong, positive relationship with precaudal length (PCL) and the girth at the pectoral fin. Negative allometric growth was exhibited for three of the fins (pectoral, upper caudal fin, and lower caudal fin) against PCL, exhibiting a significant deviation from the expected isometric growth of 2.0 for area–length relationships. There were no significant differences in morphometric relationships between geographic regions within Australia that samples were collected from. No differences between the sexes were identified; however, this may be an artifact of the lack of mature animal samples. Conversely, life stage was found to have a significant effect on the girth–length and weight–length relationships. The development of regression equations for morphometric measures allows the assessment of white shark body condition and may serve as an assessment tool to understand the potential impacts of human‐induced environmental change on white sharks.
... The other parts like skin, jaws and liver could also be used . The short fin mako sharks are among the major species in fin trade in Hong Kong , China (Cardeñosa et al., 2020) and UAE (Jabado et al., 2015) markets. These sharks are mostly a bycatch of long line and gillnets set for large pelagic fishes like tunas and bill fishes but are never been discarded back to sea because of their high value. ...
his document was prepared by a designated Indian CITES Scientific Authority, the ICAR-Central Marine Fisheries Research Institute (CMFRI), and is the result of an online workshop of the Demersal Fisheries Division of the Institute that took place during 5-7 August 2021
... These sub-Saharan countries engage in the shark fin trade because they attain economic boost from shark fin trade (Jaiteh et al., 2017). For decades, Hong Kong and China have been the center for world trade in shark fin products, processing about 50% -85% of global shark fin imports from about 85 countries (Shea & To, 2017;Jabado et al., 2015;Clarke, 2006;Schaeffer, 2004). China and Hong Kong have maintained the number one spot for shark fin trade because these countries treat shark fins as legal fishing products (Shea &To, 2017). ...
Shark is an important fishery commodity globally. However, 70% decline in the populations of shark species has cast doubt on the fishery's economic success, especially in Ghana. Therefore, studying the shark fishery activities in Ghana from the perspectives of production, socioeconomic , and management will inform key stakeholders of the approaches needed to strengthen the conservation of the fishery. We interviewed ninety-one (91) shark fishers from four important landing sites, namely; Apam, Dixcove, Tema, and Axim along the coast of Ghana using a semi-structured interview guide, and recorded their landings between April and December 2021. Our findings show that the dominant shark species landed by fishers were Sphyrna sp., C. leucas, C. carcahrias, R. acutus, C. carcharodon, I. oxyrinus, and Aliopas sp. with Sphyrna sp. and C. leucas experiencing a drastic population decline. Togo and China were the main foreign destinations for shark fin products, particularly fins of Sphyrna sp., C. leucas, and Aliopas sp. (species classified by the IUCN Red List as Endangered species). The price of shark fins during the lean season was significantly higher than in the peak period, indicating the influence of seasonality on the pricing of shark fins. The main challenges confronting shark fishing in Ghana were a decline in the population of sharks, inadequate premix fuel, and the risky nature of shark fishing activities. From the study, developing a species-specific conservation action plan through consultative approaches, community awareness programmes and enforcement of these conservation measures are some of the recommendations proposed.
... It is estimated to be declining in the Pacific and Indian Oceans because of overexploitation, including from target fisheries and bycatch (Rigby et al. 2018), mostly from longlines and nets (Martínez-Ortiz et al. 2015;Temple et al. 2019). The species is mostly retained for their fins and meat (Dent and Clarke 2015;Fields et al. 2018), although the liver, oil, and skin are also sought as derivative products (Jabado et al. 2015). The pelagic thresher shark is estimated to have a high post-release mortality rate related to capture fisheries or recreational fishing, as modeled for the A. vulpinus, with a mortality rate of 78% and 0% if hooked on the tail and mouth, respectively (Sepulveda et al. 2015). ...
Alghozali FA, Salsabila R, Gustianto MWD, Putri HMIH, Himawan MR, Yuneni RR, Hatmoro CK, Rezkiani M. 2023. Diet analyses of the pelagic thresher shark, Alopias pelagicus (Lamniformes: Alopiidae), from the Lombok Strait waters, Indonesia. Biodiversitas 24: 3708-3714. The pelagic thresher shark, Alopias pelagicus, is an endangered shark species estimated to be declining in the Pacific and Indian Oceans because of overexploitation, including from target fisheries and bycatch. Despite its importance in providing better information for species management, the ecological aspects of this species are still rarely studied. This study aims to provide information on the feeding ecology of the pelagic thresher sharks from the Lombok Strait. Stomach samples from 178 specimens were sampled from 2020-2021, and 149 stomachs that contained food contents were analyzed for species diet characterization. Prey Species Accumulation Curve slope values are <0.1 and the percentage of prey coverage for all sharks combined is 92.1%, suggesting reliable inventory in the number of prey represented. The resulting diet indexes suggest that A. pelagicus in Lombok Strait waters is a specialist predator (Ba=0.3) with few prey variations (H=2.21) and no competition between sexes and maturity stages of the species (C=0.64 and 0.81, respectively). The top three prey species found for A. pelagicus in the study area are the Auxis thazard (85.8 %IRI), Sthenoteuthis oualaniensis (8.5 %IRI), and Dasyscopelus spinosus (1.11 %IRI). A better understanding of the overlap of A. pelagicus and its diet, which includes economic fish commodities, will inform authorities to develop better fisheries and conservation management for the species in Indonesia.
... UAE is one of the main OPEC oil producers and the leading GCC states in expanding its trade potential (Khan & Alam, 2014) through the strategy of Export-Led Growth (ELG) that has been proved by Kalaitzi and Cleeve (2017). Therefore, due to the facilitation of trade and the reduction of administrative bureaucracies in the UAE, it has become the regional hub for trade (Jabado et al., 2015). As listed in Table 6.6, it is observed that the countries of the South Asian region have significant potential in the import of energy goods from this country. ...
... In Campeche, pilot interviews occurred in four communities in 2018. Interviewees were asked to identify different elasmobranch species by their common Spanish or Mayan names from unlabeled photographs, based on the method of Jabado et al. (2015). The two Pristis spp. ...
Abstract
1. Our knowledge of sawfishes remains scant for Latin America. Pristis pristis (largetooth sawfish) and Pristis pectinata (smalltooth sawfish) are critically endangered. In the Yucatán Peninsula (YP), P. pristis and P. pectinata inhabit coastal landscapes.
2. A total of 290 surveys of fishers’ local ecological knowledge (LEK), including a geospatial component, were collected; 74 literature sources and available archaeological data for the region were reviewed.
3. Interdisciplinary results show the following: the common past presence of sawfishes, their cultural significance for coastal societies, and the contemporary absence of sawfishes in coastal areas where they existed historically; sightings of juveniles were only documented by elder fishers, and only two recent narratives mention sawfishes caught incidentally 5 years ago.
4. Geospatialresultsprovideevidencefor52geographicsiteswheresawfisheswere common in the YP.
5. Results support the development of research methodologies to study human– nature interactions integrating LEK. This matters in the YP, where sociocultural values and landscapes have changed rapidly through increasing tourism development and human overcrowding.
6. The results can help conservation managers understand the past presence and contemporary loss of sawfishes, and their habitat, and contribute to understanding the defaunation of megafauna in the YP through time. This is critical for tourism and fishery ecosystem services on which communities of the YP rely for their economies.
... In Campeche, pilot interviews occurred in four communities in 2018. Interviewees were asked to identify different elasmobranch species by their common Spanish or Mayan names from unlabeled photographs, based on the method of Jabado et al. (2015). The two Pristis spp. ...
Studies using paleoecological and historical data can inform coral reef management by providing accurate ecological baselines and by pinpointing the timing, magnitude, and drivers of ecosystem declines. However, these studies have rarely been incorporated into policy and management frameworks. This working group brings together paleontologists, historical ecologists, ecologists, fisheries scientists, and conservation practitioners to develop pathways for incorporating long-term ecological data into decision-making to advance the sustainable management of reef ecosystems. Our group is focusing on Caribbean coral reefs, a geography with an abundance of historical ecological data and a track record of collaboration between reef scientists and managers. This spirit of collaboration is enhanced by the immediacy of conservation needs for reef ecosystems in this region. We are focusing on the application of long-term data to two pressing management issues for Caribbean coral reefs, which together address the most urgent local human drivers of ecosystem change – fishing and land-based pollution. In this talk, I will outline our working group’s aims and progress to date.
... However, it was regularly observed in Australia, and some island nations in the Western Pacific (e.g., French Polynesia, Palau) and Indian (e.g., Seychelles) Oceans (Simpfendorfer et al., 2021a) (Simpfendorfer et al., 2021a). It is reportedly uncommon in fisheries in Oman, India and the Maldives with no catch data available (Anderson and Ahmed, 1993, Henderson et al., 2007, Jabado et al., 2015, Simpfendorfer et al., 2021a. In Pakistan, this species used to be caught in large quantities using live baits, however, there has been a ~90% decrease in catches in recent years. ...
CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) wasopened for signature in Washington DC on 3rd March 1973, and to date has 184 Parties from across the world. If CITES is to remain a credible instrument for conserving species affected by trade, the decisions of the Parties must be based on the best available scientific and technical information. Recognizing this, IUCN and TRAFFIC have undertaken technical reviews of the proposals to amend the CITES Appendices submitted to the Nineteenth Meeting of the Conference of the Parties to CITES (CoP19).
The Analyses - as these technical reviews are known - aim to provide as objective an assessment as possible of each amendment proposal against the requirements of the Convention, as agreed by Parties and laid out in the listing criteria elaborated in Resolution Conf. 9.24 (Rev. CoP17) and other relevant Resolutions and Decisions. To ensure the Analyses are as accessible as possible to all Parties, we have created a bespoke webpage where the Analyses can be downloaded individually by proposal or in full (see https://citesanalyses.iucnredlist.org/).
... There has been a surge on the studies focused on fisheries of elasmobranch in the Arabian Sea and contiguous sea (Chen, 1996;Dent and Clarke, 2015;Dulvy et al.,2014;Haque et al., 2018;Henderson et al., 2004;2016;Jabado and Spaet, 2017;Jabado et al., 2014Jabado et al., , 2015Jabado et al., , 2018Karnard et al., 2020). Jabado and Spaet (2017) have given a detailed description of shark fisheries including stingrays of the Arabian Sea including Pakistan. ...
Stingrays belonging to Family Dasyatidae are commercially exploited in Pakistan (Northern Arabian Sea) since long and mainly landed as bycatch of trawling and bottom-set gillnet fishing, In some areas along Sindh and Balochistan coast target stingrays fisheries based on fixed gillnet used to main source of their landings. It is estimated that their commercial landings ranged between 42,000 m. tons in 1979 to 7,737 metric tons in 2019. Analysis of the landing data from Karachi Fish Harbor (the largest fish landing center in Pakistan) revealed that 27 species of stingrays belonging to 14 genera are regularly landed (January 2019-December 2019). Smooth coloured stingrays (Himantura randalli/M. arabica/M.bineeshi) contributed about 66.94 % in total annual landings of stingrays followed by cowtail and broadtail stingrays (Pastinachus sephen and P. ater) which contributed 24.42 %. Spotted/ocellated/reticulated stingrays (Himantura leoparda, H. tutul, H. uarnak and H. undulata) contributed and 5.71 % in total annual landings of stingrays. Scaly whipray (Brevitrygon walga) and aharpnose stingray (Maculabatis gerrardi) contributed about 1.95 % and 0.98 % in total annual stingray landings of stingrays respectively. Three species leopard whipray (Hiamntura undulata), round whipray (Maculabatis pastinacoides) and Indian sharpnose stingray (Telatrygon crozieri) are reported for the first time from Pakistan coast. There is an important aimed fisheries for stingrays based in some coastal villages along Balochistan coast where fixed bottom set gillnet placed in shallow waters (15-20 m.), however, these fishes are also caught as by-catch of gillnetting and shrimp trawling. The paper discusses about commercial landings and conservation aspects of stingrays in Pakistan. It urges for enactment of national and provincial legislation for protection of stingrays as well as for placing some of the species which are either critically endangered, vulnerable or near threatened to be placed CITES appendices. It also urges for evaluation of a large number stingrays which have not been assessed for their IUCN Red List listings.
... 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]. ...
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.
... 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). ...
• 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.
... 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 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). ...
... 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. ...
... 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. ...
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.
... 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). ...
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.
... 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). ...
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.
... 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]. ...
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.
... 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. ...
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]. ...
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 FST showed three significant subdivisions in Indonesia (FST = 0.442; P < 0.001), with separated populations for Aceh and West Papua, and mixed between Balikpapan and Lombok (FST = 0.044; P = 0.091). In contrast, genetic homogeneity was observed within the population of the Western Indian Ocean (FST = –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 (FST = 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.
... 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] . ...
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.
... 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]. ...
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.
... 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. ...
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.
... 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. ...
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.
... 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]. ...
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.
In the 20 years since the IUCN SSC Shark Specialist Group’s first status report (2005), much has changed for
sharks, rays and chimaeras. This report updates our understanding, and the scope of information reflects the scale
of these two decades of change. The breadth of research topics has expanded, mirroring the inclusion of a greater
diversity of species, and attention is being trained on the emerging threats and the accelerating global changes to
aquatic ecosystems. The 2005 report heralded a sea change for sharks, rays and chimaeras, whose historical
obscurity in policy, conservation and fisheries management was a serious concern. In this report, the increased focus that was called for is now apparent
in the scale of work happening across the planet.
In the 20 years since the IUCN SSC Shark Specialist Group’s first status report (2005), much has changed for sharks, rays and chimaeras. This report updates our understanding, and the scope of information reflects the scale of these two decades of change. The breadth of research topics has expanded, mirroring the inclusion of a greater diversity of species, and attention is being trained on the emerging threats and the accelerating global changes to aquatic ecosystems. The 2005 report heralded a sea change for sharks, rays and chimaeras, whose historical obscurity in policy, conservation and fisheries management was a serious concern. In this report, the increased focus that was called for is now apparent in the scale of work happening across the planet. This particular section/file focuses on the Indian Ocean. For the entire report please visit: https://portals.iucn.org/library/node/52102
This species is a common inhabitant on the Australian continental shelf south of 30°S from Byron Bay (New South Wales) to the Houtman Abrolhos (Western Australia), including Tasmania, but records from York Sound (northern Western Australia) and Moreton Bay (Queensland) are questionable (Huveneers and Simpfendorfer 2015). In New Zealand, one specimen of this species is reported from waters near Wellington (Cox and Francis 1997; Compagno 2001; Last and Stevens 2009). The specimen from New Zealand is a female caught in 1954 (Cox and Francis 1997) and a voucher specimen held at the NMNZ (Paulin et al. 1989).
This edited volume brings together a diverse and rich set of contributions on the Arabian Peninsula. Ranging from history, field linguistics, and cultural studies these essays address the diversity of languages, ways of life, and natural environments that have marked the region throughout its history.
The book stems from the intellectual exchange and collaboration fostered by a virtual workshop that met regularly in 2020-21 and which drew participants from within and beyond the academy. The contributions gathered in this volume highlight the need for a better understanding of a region that hosts a vast amount of culturally and linguistically diverse material, often in a precarious state of conservation.
Diversity Across the Arabian Peninsula argues for the importance of holistic, community-based, and interdisciplinary approaches to linguistic endangerment and deep social and cultural changes: there is no documentation of language without attention to language use, the material lifeworld and its ecology, and social and cultural setting. Such research is enriched and made more impactful through collaboration with communities and scholars from the Global South. The essays in this volume thus spearhead a contextualized study of South Arabian linguistic varieties and their connection with the natural and cultural world they inhabit.
Despite global conservation efforts, elasmobranchs still face increased fishing pressure due to high demand for their products. Although certain species have been afforded international and local protection, the high value of their products in international markets incentivises the trade of protected species covertly within marketed fish products. To address the problem, we amplified fragments of the cytochrome oxidase subunit I gene (approximately 595 base pairs) from 164 elasmobranch fins collected from fish markets in Tanzania to test whether protected species and those of conservation concern are among these specimens. Similarly, we conducted 130 in-depth key informant interviews with stakeholders involved in the elasmobranch-fin trade to gather diverse perspectives on the factors perpetuating the trade. Our findings revealed fifteen elasmobranch species, with requiem sharks (Carcharhinidae) and wedgefishes (Rhinidae) accounting for 44.1% and 33.8% of the fins, respectively. Alarmingly, over 70% of the traded fins originated from threatened elasmobranchs, with 36.8% sourced from critically endangered species. Unexpectedly, almost 9% of the traded fins were sourced from two nationally protected species, Carcharhinus longimanus and Alopias pelagicus, highlighting the existence of regulatory gaps that require immediate attention. Similarly, 91.2% of traded fins were sourced from CITES-listed species, emphasising the severity of the problem. The interviews highlighted technological challenges in tracking the trade, limited awareness of trade impacts on elasmobranch sustainability, scarce surveillance resources, inadequate training to identify routes and offenders and lack of public support as the main factors perpetuating the trade. Addressing these issues necessitates a total ban on elasmobranch-fin trade, coupled with increased funding for enforcement agencies, providing specialised training for law enforcement personnel, launching public awareness campaigns and promoting community-based monitoring and collaboration with international organisations. By doing so, Tanzania can effectively safeguard the sustainability of threatened elasmobranchs and advance global conservation efforts for these fishes. K E Y W O R D S DNA barcoding, East Africa, shark-fin trade, southwestern Indian Ocean, Tanganyika 2 of 12 | RUMISHA et al.
Habitat loss and degradation are currently the main anthropogenic causes of species extinctions. The root cause is human overpopulation. This unique volume provides, for the very first time, a comprehensive overview of all threatened and recently extinct mammals, birds, reptiles, amphibians, and fishes within the context of their locations and habitats. The approach takes a systematic examination of each biogeographic realm and region of the world, both terrestrial and marine, but with a particular emphasis on geographic features such as mountains, islands, and coral reefs. It reveals patterns useful in biodiversity conservation, helps to put it all into perspective, and ultimately serves as both a baseline from which to compare subsequent developments as well as a standardization of the way threatened species are studied.
Dampak tingginya pemanfaatan ikan hiu dan pari menyebabkan ketersediaan di alam berkurang bahkan ada yang mulai punah, sehingga beberapa diantaranya dilindungi menurut peraturan perundangan nasional dan konvensi internasional. Salah satu bentuk pengendalian agar keberadaan hiu dan pari terjaga adalah melalui penerbitan dokumen perizinan pada pelaksanaan pemanfaatan dan peredarannya. Penelitian ini bertujuan untuk meberikan informasi tentang pelaksanaan pengendalian dan pemanfaatan hiu maupun pari di BPSPL Denpasar dan wilayah kerjanya. Pengumpulan data melalui wawancara, observasi dan dokumentasi menunjukkan bahwa pada tahun 2021 pengendalian dan pemanfaatan hiu dan pari telah dilakukan melalui penerbitan dokumen perizinan yaitu rekomendasi dan angkut jenis ikan, jumlah dokumen yang dikeluarkan sebanyak 1.021 surat untuk peredaran lokal dengan 26 kota tujuan dan 1.132 surat untuk peredaran eksport dengan 20 negara tujuan eksport. Ikan hiu yang diedarkan sebanyak 45 jenis dengan jumlah 2.643.397,60 kg, sedangkan ikan pari yang diedarkan sebanyak 17 jenis dengan jumlah 148.429,70 kg. Produk yang diedarkan berupa (1) bentuk daging, yaitu berupa daging utuh, daging glondongan, potongan daging dan daging olahan; (2) bentuk sirip dan kulit, yaitu berupa sirip kering, kulit kering dan sirip olahan; dan (3) bentuk hidup. Pelaksanaan pengendalian dan pemanfaatan hiu dan pari memberikan kontribusi PNBP Rp732.268.882,00.
Sharks are important component of the coastal and offshore fisheries of Pakistan. A total of 79 species of sharks belonging to Infraclass Selachii (Subclass: Elasmobranchii) and 6 orders are recorded from Pakistan. Order Carcharhiniformeswas observed to be most prolific taxon represented by 48 species belonging to 6 families. Commercially important genus Carcharhinus is represented 18 species whereas genus Chiloscyllium by 5 species, genus Sphyrna by 4 species and genus Alopias by 3 species whereas other genera are represented by either 2 or 1 species. Three species namely Pondicherry shark (Carcharhinus hemiodon), Ganges shark (Glyphis gangeticus) and Indian sand tiger (Carcharias tricuspidatus) used to commonly occurring in Pakistan but now seem to be locally extinct as no confirmed record of their occurrence is available far the last about 40 years. The paper reviewed the historical records of shark species occurring in Pakistan resolving some of the issues in their taxonomy.
Guitarfish and wedgefish are commercially exploited in Pakistan (Northern Arabian Sea) since long. It is estimated that their commercial landings ranged between 4,206 m. tons in 1981 to 403 metric tons in 2011. Analysis of the landing data from Karachi Fish Harbor (the largest fish landing center in Pakistan) revealed that seven species of guitarfish and wedgefish are landed (January 2019-February 2020 data). Granulated guitarfish (Glaucostegus granulatus) contributed about 61.69 % in total annual landings of this group followed by widenose guitarfish (G. obtusus) contributing about 23.29 % in total annual landings of guitarfish and wedgefish. Annandale's guitarfish (Rhinobatos annandalei) and bowmouth guitarfish (Rhina ancylostoma) contributed 7.32 and 5.97 % in total annual landings respectively. Spotted guitarfish (R. punctifer), Halavi ray (G. halavi), smoothnose wedgefish (Rhynchobatus laevis) and Salalah guitarfish (Acroteriobatus salalah) collectively contributed about 1.73 % in total annual landings. Smoothnose wedgefish (R. laevis) is rarest of all the members of Order Rhinopristiformes. G. granulatus, G. obtusus, R. ancylostoma, G. halavi and R. laevis are critically endangered according to IUCN Red List whereas A. salalah is near threatened and R. annandalei is data deficient. There are no aimed fisheries for guitarfish and wedgefish in Pakistan but these fishes are mainly caught as by-catch of bottom-set gillnetting and shrimp trawling. Some aspects of biology of these species are also presented in the paper.
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.
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.
• 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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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/
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.
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
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.
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.
The conservation and management of sharks on a species-specific basis is a pressing need because of the escalating demand for shark fins and the recognition that individual shark species respond differently to exploitation. Difficulties with the identification of many commonly fished sharks and their body parts has resulted in a global dearth of catch and trade information, making reliable assessment of exploitation effects and conservation needs for individual species nearly impossible. We developed and tested a highly streamlined molecular genetic approach based on species-specific, polymerase-chain-reaction primers in an eight-primer multiplex format to discriminate simultaneously between body parts from six shark species common in worldwide pelagic fisheries. The species-specific primers are based on DNA sequence differences among species in the nuclear ribosomal internal transcribed spacer 2 locus. The primers and multiplex format accurately and sensitively distinguished samples from each of three lamnid ( Isurus oxyrinchus, Isurus paucus, and Lamna nasus) and three carcharhinid ( Prionace glauca, Carcharhinus obscurus, and Carcharhinus falciformis) species from all but one other shark species encountered in the North Atlantic fishery. Furthermore, the three lamnid primers were robust enough in their discriminatory power to be useful for species diagnosis on a global scale. Preliminary testing of dried fins from Asian and Mediterranean commercial markets suggests that our genetic approach will be useful for determining the species of origin of detached fins, thus allowing the monitoring of trade in shark fins for conservation assessment. Our approach will also facilitate detection of products from protected and other at-risk shark species and may prove useful as a model for development of the high-throughput, genetic, species-diagnosis methods typically required in conservation and management contexts.
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.
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.
The demand for shark fins is arguably the most important determinant of the fate of shark populations around the world. This paper examines the role that social and economic factors in China play in driving the trade both historically and under current trends of economic growth. The use of shark fin as a traditional and socially important luxury food item, along with rapidly expanding consumer purchasing power is expected to place increasing pressure on available resources. At the same time, the migration of the trade from its former center in Hong Kong to Mainland China has resulted in a severe curtailment of the ability to monitor and assess impacts on shark populations. Although recent international policy responses to this issue have resulted in the implementation of shark finning bans in some areas, these measures are likely to encourage full use of dead sharks; i.e. discourage carcass discards, as called for under the FAO International Plan of Action-Sharks, but not reduce shark mortality.
Overexploitation threatens the future of many large vertebrates. In the ocean, tunas and sea turtles are current conservation
concerns because of this intense pressure. The status of most shark species, in contrast, remains uncertain. Using the largest
data set in the Northwest Atlantic, we show rapid large declines in large coastal and oceanic shark populations. Scalloped
hammerhead, white, and thresher sharks are each estimated to have declined by over 75% in the past 15 years. Closed-area models
highlight priority areas for shark conservation, and the need to consider effort reallocation and site selection if marine
reserves are to benefit multiple threatened species.
The burgeoning and largely unregulated trade in shark fins represents one of the most serious threats to shark populations worldwide. In Hong Kong, the world's largest shark fin market, fins are classified by traders into Chinese-name categories on the basis of market value, but the relationship between market category and shark species is unclear preventing identification of species that are the most heavily traded. To delineate these relationships, we designed a sampling strategy for collecting statistically sufficient numbers of fins from traders and categories under conditions of limited market access because of heightened trader sensitivities. Based on information from traders and morphological inspection, we hypothesized matches between market names and shark taxa for fins within 11 common trade categories. These hypotheses were tested using DNA-based species identification techniques to determine the concordance between market category and species. Only 14 species made up approximately 40% of the auctioned fin weight. The proportion of samples confirming the hypothesized match, or concordance, varied from 0.64 to 1 across the market categories. We incorporated the concordance information and available market auction records for these categories into stochastic models to estimate the contribution of each taxon by weight to the fin trade. Auctioned fin weight was dominated by the blue shark (Prionace glauca), which was 17% of the overall market. Other taxa, including the shortfin mako (Isurus oxyrinchus), silky (Carcharhinus falciformis), sandbar (C. obscurus), bull (C. leucas), hammerhead (Sphyrna spp.), and thresher (Alopias spp.), were at least 2-6% of the trade. Our approach to marketplace monitoring of wildlife products isparticularly applicable to situations in which quantitative data at the source of resource extraction are sparse and large-scale genetic testing is limited by budgetary or other market access constraints.
Despite growing concerns about overexploitation of sharks, lack of accurate, species-specific harvest data often hampers quantitative stock assessment. In such cases, trade studies can provide insights into exploitation unavailable from traditional monitoring. We applied Bayesian statistical methods to trade data in combination with genetic identification to estimate by species, the annual number of globally traded shark fins, the most commercially valuable product from a group of species often unrecorded in harvest statistics. Our results provide the first fishery-independent estimate of the scale of shark catches worldwide and indicate that shark biomass in the fin trade is three to four times higher than shark catch figures reported in the only global data base. Comparison of our estimates to approximated stock assessment reference points for one of the most commonly traded species, blue shark, suggests that current trade volumes in numbers of sharks are close to or possibly exceeding the maximum sustainable yield levels.
Evidence for severe declines in large predatory fishes is increasing around the world. Because of its long history of intense fishing, the Mediterranean Sea offers a unique perspective on fish population declines over historical timescales. We used a diverse set of records dating back to the early 19th and mid 20th century to reconstruct long-term population trends of large predatory sharks in the northwestern Mediterranean Sea. We compiled 9 time series of abundance indices from commercial and recreational fishery landings, scientific surveys, and sighting records. Generalized linear models were used to extract instantaneous rates of change from each data set, and a meta-analysis was conducted to compare population trends. Only 5 of the 20 species we considered had sufficient records for analysis. Hammerhead (Sphyrna spp.), blue (Prionace glauca), mackerel (Isurus oxyrinchus and Lamna nasus), and thresher sharks (Alopias vulpinus) declined between 96 and 99.99% relative to their former abundance. According to World Conservation Union (IUCN) criteria, these species would be considered critically endangered. So far, the lack of quantitative population assessments has impeded shark conservation in the Mediterranean Sea. Our study fills this critical information gap, suggesting that current levels of exploitation put large sharks at risk of extinction in the Mediterranean Sea. Possible ecosystem effects of these losses involve a disruption of top-down control and a release of midlevel consumers.
Anecdotal evidence suggests that sharks are being targeted in the United Arab Emirates artisanal fishery. However, little information is available on this fishery and baseline information is essential for understanding its impact on shark populations in the Arabian/Persian Gulf, and for managing sharks in this region.
The aim of this study was to investigate the artisanal shark fishery and gain an insight into the social, motivational and economic drivers behind it. Fishery characteristics were examined and the effect of fishing on local shark stocks assessed by interviewing Emirati fishermen across the country (n = 126).
Sharks were found to be increasingly targeted owing to their high value in the global fin trade industry. The majority of fishermen (80%) confirmed that changes in species composition, abundance and sizes of sharks have been continuing for more than two decades, mainly because of overfishing, raising concerns about the sustainability of this fishery.
Results suggest that sharks are likely to be overexploited and that management measures will need to take into account the precautionary principle. There is an urgent need to formulate long‐term and effective conservation and management plans to prevent further declines in a number of species.
Additional efforts should be directed to quantify the ecological implications of the observed changes and determine if these are aggravated by the life‐history traits of the fished species. Such implications should be considered when assessing the sustainability of local fisheries.
The data gathered can now serve as a reference to managers, fisheries scientists and other stakeholders to prioritize future research as well as lay foundations for the development and implementation of national management plans for the protection and conservation of sharks.
Copyright © 2014 John Wiley & Sons, Ltd.
Between 1966 and 1989,255 shortfin mako sharks Isurus oxyrinchus were caught in the gill nets which protect the tourist beaches of Natal. The catch rate showed no trend, fluctuating about a mean of 0,34 sharks·km-net−1·year−1. Catches were highest between May and November, when the water tends to be cooler. The sex ratio was 1,4 males to 1 female. Specimens ranged in size from 84 to 276 cm precaudal length, with a mode of 191–195 cm for males and 251–255 cm for females. Males matured at 160-170 cm and females at approximately 220 cm. Catches included two recently fertilized females and two with well-developed embryos. External injuries were found on 14 per cent of males examined and 41 per cent of females. Elasmobranchs were the most common prey category, occurring in 60 per cent of stomachs containing food, followed by teleosts at 40 per cent. Most of the elasmobranch prey were sharks shorter than 1 m.
There are many fish landing areas in southern Iran, distributed all along the coastline, and despite gradually increasing
effort, the total catch has fluctuated in recent years. This study examines the technical efficiency of the fishing industry,
and identifies factors that could be causing inefficiency. A stochastic production function among fishery vessels is estimated.
Technical efficiency measures the ability of firms to maximize output using a given set of inputs and technologies. The results
indicate that technical efficiency in the fishery is relatively low, and that wooden vessels of medium size are more efficient
than small fibreglass vessels. Both skippers' socio-economic drivers and vessel instrumentation have a significant impact
on efficiency. Ownership of two-way radio and ownership of GPS are important considerations that influence fishing efficiency,
and the skipper's level of education and experience are qualities that also affect it. Owner-operated vessels and younger
skippers are more efficient than others. Understanding these constraints may contribute to increasing the efficiency of the
Iranian fishery in the Persian Gulf.
Although commercial kits are available for automated DNA extraction, 'artisanal' protocols are not. In this study, we present a silica-based method that is sensitive, inexpensive and compliant with automation. The effectiveness of this protocol has now been tested on more than 5000 animal specimens with highly positive results. Ivanova). The present study seeks to overcome these constraints. Our study evaluated the effectiveness of several com- mercial glass fibre filtration (GF) plates, the core functional component in all silica-based DNA extraction kits. We worked only with 96-well plates that appeared structurally compatible with robotic systems. Specifically, we compared the performance of seven GF plates — two manufactured by BioLynx (B1, B2), three by PALL (P1-3) and two by Whatman (W1, W2). The B1 plate (no. F2008) was a 0.7- µ m glass fibre with 0.8 mL well; B2 (no. F2007) was a 1.0- µ m glass fibre with 0.8 mL well; P1 (no. 5051) was a 1.0- µ m glass fibre with 1 mL well; P2 (no. 5053) was a 3.0- µ m glass fibre media/0.2 µ m Bio-Inert membrane with 1 mL well; P3 (no. 5031) was a 1.0- µ m glass fibre media with 350 µ L well; W1 (no. 7505-0003) was a mini prep DNA binding plate with 0.8 mL well and W2 (no. 7700-7801) was a Unifilter plate with glass fibre media with 0.8 mL well. We began by identifying both buffer systems and protocols that enabled the use of these GF plates for manual DNA extraction. We then tested their performance under automation with a Biomek NX liquid-handling station (Beckman-Coulter) equipped with a filtration manifold. To provide a solid test of performance, we compared these results with those from a high performance commercial kit — the NucleoSpin96 (Machery-Nagel), hereafter termed the MN kit (Hajibabaei et al . 2005). Our performance comparisons employed DNA extracted from frozen tissues of six mammal species ( Glaucomys volans , Sorex fumeus , Clethrionomys gapperi , Blarina brevicauda,
This study investigates the current state of the directed artisanal shark fishery off Unguja Island, Zanzibar, with a focus on the East Asian shark fin trade and its impact on the utilization of this valuable marine resource. The study concentrates on the two fish markets in Stone Town: Malindi and Darajani. Large fish are brought to these markets both from nearby waters and from other coastal towns on the island. Data was gathered through observation of the type and number of sharks landed, fishing practices employed, and sale of shark products, particularly fins. Local fin traders and exporters were interviewed to determine the characteristics of the local market, the relative value of different fin types, and changes in volume and demand over time. Local fishermen were interviewed to investigate directed exploitation of sharks, changes in shark populations over time, and the possible influence of the fin trade on fishing activities. Results provide a preliminary insight into the current status of the directed shark fishery, the logistics of the fin trade, and conservation implications for coastal shark populations.
Reliable recovery of the 5'''' region of the cytochrome c oxidase 1 (COI) gene is critical for the ongoing effort to gather DNA barcodes for all fish species. In this study, we develop and test primer cocktails with a view towards increasing the efficiency of barcode recovery. Specifically, we evaluate the success of polymerase chain reaction amplification and the quality of resultant sequences using three primer cocktails on DNA extracts from repre- sentatives of 94 fish families. Our results show that M13-tailed primer cocktails are more effective than conventional degenerate primers, allowing barcode work on taxonomically diverse samples to be carried out in a high-throughput fashion.
Despite the importance of observers to collect data for effective fisheries management worldwide, their species-identification abilities are rarely assessed. Misidentifications could compromise observer data particularly in diverse, multi-species fisheries such as those in the tropics where visual identification is challenging. Here, we provide the first estimates of the ability of scientific observers to identify five species of morphologically similar carcharhinid sharks (Carcharhinus leucas, C. amboinensis, C. tilstoni, C. sorrah and C. brevipinna) in a fishery in northern Australia. We compared observer field identifications of sharks with genetic validation (814 bp mtDNA NADH dehydrogenase subunit 4) to quantify species identification errors. We used binomial generalised linear models to determine the influences of species, gender, total length, and the observer's experience on identification error. We found that identification error (∼20%) depended predominately on the species in question (highest error for C. tilstoni). Male sharks were misidentified less frequently than females, and error decreased marginally with increasing total length. Surprisingly, we found no statistical evidence that observer experience influenced identification error. Our results provide the first benchmark of identification accuracy of observers for carcharhinid sharks in northern Australia and show that estimates of error in species identifications need to be incorporated into management strategies to ensure successful recovery of the many recently over-fished shark populations.
Catch and effort data from a fishery-independent longline survey in the western North Atlantic were used to investigate the biology, distribution and abundance of pelagic sharks. Data were restricted to the period from 1977 to 1994, and for the months of June–August. Catches were dominated by the blue shark (Prionace glauca), with smaller numbers of shortfin mako (Isurus oxyrinchus), porbeagle (Lamna nasus), thresher (Alopias spp.) and silky (Carcharhinus falciformis) sharks. Detailed analysis was restricted to P. glauca due to small sample sizes for the other species. Male blue sharks were caught more often than females. The catches included juveniles and adults of both sexes but very few adult females. Annual sex ratios varied, but normally favored males. Monthly sex ratios were even in June, but favored males in July and August. Due to differences in occurrence between males and females, distribution and abundance data were analyzed separately for each sex. Male catch per unit effort (CPUE) was highest between 15 and 20 °C, while female CPUE peaked at approximately 15 °C and decreased with increasing water temperatures. CPUE for males and females were standardized using a generalized linear model with years, months and day-night as factors. Males showed an approximately 80% decline between the mid-1980s and the early 1990s, while a significant change in female catch rates could not be demonstrated. The results of the analyses are discussed in relation to fishery-dependent studies in the western North Atlantic, along with previous work on the biology and distribution of pelagic sharks.
This study gives an account of spatial and temporal distribution of whale shark Rhincodon typus catch events in China on the basis of historical records and information obtained from interviews with fishing industry stakeholders. A total of 186 R. typus were recorded with key harvest areas identified as in Hainan and Zhejiang, and the peak catching seasons were May to June and September to October. Aspects of the R. typus trade are discussed, including products, markets and the process. The results suggest that R. typus is increasingly becoming a targeted resource in China as a consequence of fierce competition for large shark fins and an emerging local market for consumption of all body parts. Current obstacles and potential measures for sustainable exploitation and trade of R. typus are discussed.
Fisheries managers and scientists worldwide are struggling with a lack of basic information for many shark and ray species. One factor hampering the data collection is inaccurate identification of many chondrichthyan species and their body parts. Morphologically similar species, and specimens which are poorly preserved or have had key diagnostic features removed, can be difficult to identify. This study examined DNA barcoding as a method to identify shark species from dried fins, confiscated from a vessel fishing illegally in Australian waters. 211 left pectoral fins were examined. 18 either did not provide a sequenceable product or yielded a microbial sequence, while 193 fins (91.5%) provided a chondrichthyan sequence. All of these could be matched to reference specimens in a DNA barcode database, and so were able to be identified. 27 species were detected, 20 species of sharks and seven species of rays The most abundant species (22% of fins) was Carcharhinus dussumieri. Many of these species are listed on the World Conservation Union (IUCN) Red List and include one, Anoyxpristis cuspidata (3%), rated as critically endangered. Fishing authorities can use DNA barcoding to gather data on which chondrichthyan species are targeted by illegal fishers, information that will greatly assist in management and conservation.