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In June 2024, a large female oceanic whitetip shark (Carcharhinus longimanus) was observed near San Andres Island, Colombia, bearing at least 41 healed circular scars on its skin. These scars, resembling those left by cookiecutter sharks on large teleost species, suggest repeated predation events. Cookiecutter sharks typically leave one or two bite marks per prey item, with a small percentage showing five or more marks. The observation implies frequent depth overlap between the mesopelagic cookiecutter sharks and the epipelagic oceanic whitetip shark in the Caribbean Sea. [ABSTRACT FROM AUTHOR]

Chondrichthyan fishes are among the most threatened vertebrates on the planet because many species have slow life histories that are outpaced by intense fishing. The Western Central Atlantic Ocean, which includes the Greater Caribbean, is a hotspot of chondrichthyan biodiversity and abundance, but has been characterized by extensive shark and ray fisheries and a lack of sufficient data for effective management and conservation. To inform future research and management decisions, we analysed patterns in chondrichthyan extinction risk, reconstructed catches and management engagement in this region. We summarized the extinction risk of 180 sharks, rays and chimaeras, including 66 endemic and 14 near‐endemic species, using contemporary IUCN Red List assessments. Over one‐third (35.6%) were assessed as Vulnerable, Endangered or Critically Endangered, primarily due to overfishing. Reconstructed catches from 1950 to 2016 peaked in 1992, then declined by 40.2% thereafter. The United States, Venezuela and Mexico were responsible for most catches in the region and hosted the largest proportions of the regional distributions of threatened species, largely due to having extensive coastal habitats in their Exclusive Economic Zones. The quantity and taxonomic resolution of fisheries landings data were poor in much of the region, and national‐level regulations varied widely across jurisdictions. Deepwater fisheries represent an emerging threat, although many deepwater chondrichthyans currently have refuge beyond the depths of most fisheries. Regional collaboration as well as effective and enforceable management informed by more complete fisheries data, particularly from small‐scale fisheries, are required to protect and recover threatened species and ensure sustainable fisheries. [ABSTRACT FROM AUTHOR]

One third of chondrichthyan species (sharks, rays, and chimeras) are threatened with extinction, mainly due to unsustainable fishing. Large accessible international markets for meat and luxury products like dried fins can help drive overfishing by encouraging targeted capture or retention of high‐value export species. If this is common, then species in international trade could have heightened extinction risk. Here, we examined the species composition of the Hong Kong shark fin market from 2014 to 2018, finding that traded species disproportionately occur in threatened categories (70.9%) and all premium value species are threatened. A small number of cosmopolitan species dominate the trade, but noncosmopolitan coastal species are still traded at concerning levels given their limited distribution. These coastal species are not generally subject to retention prohibitions, fisheries management, or international trade regulations and without management many could become extinct. The conservation potential of international trade regulations alone for coastal chondrichthyans depends on the extent to which overfishing is driven by export markets; socioeconomic studies of coastal fishing communities are needed to make this determination. Nonetheless, adding international trade regulations for more coastal shark species that are in the fin trade could prompt broad engagement with overfishing in nations lacking effective management. [ABSTRACT FROM AUTHOR]

Illegal wildlife trade is a major global threat to biodiversity. Environmental authorities around the world face many challenges enforcing and implementing laws intended to protect wild species. Wildlife forensic protocols can help to solve many of these implementation and enforcement issues.Matamata turtles comprise two different species that look identical (Chelus fimbriata, Chelus orinocensis), which are geographically separated into the Amazon and Orinoco river basins, respectively, in South America. The trade in matamata turtles (Chelus sp.) is illegal in Colombia and law enforcement officers need to identify confiscated individuals to the species level in order to return them to the correct river basin. This is a time‐sensitive problem because increasing time in captivity can lead to mortality and imposes logistical and financial burdens on resource managers.This article presents the development of a reliable, potentially field‐based, fast (~2 h), and cost‐effective (~USD$1 per sample identified) real‐time polymerase chain reaction assay to identify live matamata turtles to the species level, which facilitates accurate and fast translocation back to the correct river‐of‐origin.This assay was applied in a real law enforcement scenario where confiscated matamata turtles were quickly identified as C. orinocensis, showing that they should be returned to the Orinoco basin. This research highlights the practicality and usefulness of these kinds of protocols to solve wildlife trade issues faced by law enforcement officers, and provides a blueprint for the development and implementation of field‐based molecular protocols to enhance the enforcement and implementation of laws intended to protect wildlife subject to illegal trade.Given the widespread detection of illegal trade in wildlife and the threat that it poses to biodiversity, it is critical that these types of protocols and collaborative efforts among all stakeholders continue to be developed and implemented. [ABSTRACT FROM AUTHOR]

The silky shark is the second most common shark in Southeast Asia's dried fin markets and is managed in the Atlantic Ocean by the International Commission for the Conservation of Atlantic Tuna (ICCAT) and by three Indo‐Pacific regional fisheries management organizations (RMFOs). The International Commission for the Conservation of Atlantic Tuna reports ∼ 7% of global silky landings but there is a moratorium on the export of their fins. During a 4‐year period (2014–2017) we used genetic differentiation observed between Atlantic and Indo‐Pacific silky sharks to assess the contribution of Atlantic individuals to fins randomly obtained in the two largest shark fin markets in the world, Hong Kong and Guangzhou, China (N = 604). We did not detect any Atlantic fins in either market despite robust sampling effort with an estimated Indo‐Pacific contribution of 99.8% to these markets. These findings indicate that supply chains for silky shark fins in Hong Kong and Guangzhou primarily originate in the Indo‐Pacific and are mainly under the purview of three Regional Fisheries Management Organizations. Our results are consistent with the possibility that ICCAT parties have achieved high compliance with the ban on silky sharks. We suggest research and monitoring improvements that could enhance our understanding of the global trade of silky sharks and enable better fisheries management. [ABSTRACT FROM AUTHOR]

Species-specific monitoring through large shark fin market surveys has been a valuable data source to estimate global catches and international shark fin trade dynamics. Hong Kong and Guangzhou, mainland China, are the largest shark fin markets and consumption centers in the world. We used molecular identification protocols on randomly collected processed fin trimmings (n = 2000) and non-parametric species estimators to investigate the species composition of the Guangzhou retail market and compare the species diversity between the Guangzhou and Hong Kong shark fin retail markets. Species diversity was similar between both trade hubs with a small subset of species dominating the composition. The blue shark (Prionace glauca) was the most common species overall followed by the CITES-listed silky shark (Carcharhinus falciformis), scalloped hammerhead shark (Sphyrna lewini), smooth hammerhead shark (S. zygaena) and shortfin mako shark (Isurus oxyrinchus). Our results support previous indications of high connectivity between the shark fin markets of Hong Kong and mainland China and suggest that systematic studies of other fin trade hubs within Mainland China and stronger law-enforcement protocols and capacity building are needed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Contemporary global demand for shark commodities such as fins, meat, and liver oil, is arguably the main driver of shark overexploitation trends observed in the last three decades. Shark are most commonly traded for their fins to be used in different Asian countries as a soup delicacy. Nevertheless, shark meat trade has increased substantially in the last decade, while liver oil trade is still largely unknown. Shark liver oil is highly valuable in the cosmetic industry as a moisturizer, while shark meat is directly consumed in a large number of countries but the whole extent of its uses is unknown. Here I used a multiplex mini-barcode PCR protocol to identify traces of shark DNA in beauty care and pet food products, in order to identify them to the genus and/or species level. All products tested for this study were not labeled as containing elasmobranch-based ingredients. I tested 87 pet food products, 63% amplified successfully, and 70% of those were identified as the Endangered shortfin mako shark. I also tested twenty-four cosmetics, where 3 (12.5%) amplified successfully, containing blue shark, scalloped hammerhead and blacktip shark. This study highlights the need for more labeling controls, since shark populations could benefit if consumers have the alternative to choose whether or not to purchase products containing threatened shark species in order to decrease the global demand. [ABSTRACT FROM AUTHOR]

Abstract: Trade‐driven overexploitation threatens many sharks. Twelve of the world's most vulnerable shark species have been listed on the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to regulate internationally traded products such as meat and dried fins. CITES records indicate that Hong Kong was the world's top legal importer of dried fins from listed sharks in 2015 (N = 8 species at that time), but traded a relatively small volume, with a few partners, in a small number of shipments (16). In contrast two CITES Appendix II listed hammerheads were consistently the fourth and fifth most common species (out of >80) in processed fin trimmings (N = 9,200) collected randomly from the Hong Kong retail dried fin market from February 2014 to December 2016 and were found in 100% of sampling events and in 66% of sampled retail vendors. This difference, and the fact that exporting nations previously known to land these species were not among those to report trade to CITES, suggest that listed species were often imported without CITES documentation in 2015. There are a number of incentives for trade hubs to meet their obligations to this treaty, which they could achieve by scaling up monitoring capacity and increasing inspection efficiency. [ABSTRACT FROM AUTHOR]

Protecting sharks from overexploitation has become global priority after widespread population declines have occurred. Tracking catches and trade on a species-specific basis has proven challenging, in part due to difficulties in identifying processed shark products such as fins, meat, and liver oil. This has hindered efforts to implement regulations aimed at promoting sustainable use of commercially important species and protection of imperiled species. Genetic approaches to identify shark products exist but are typically based on sequencing or amplifying large DNA regions and may fail to work on heavily processed products in which DNA is degraded. Here, we describe a novel multiplex PCR mini-barcode assay based on two short fragments of the cytochrome oxidase I (COI) gene. This assay can identify to species all sharks currently listed on the Convention of International Trade of Endangered Species (CITES) and most shark species present in the international trade. It achieves species diagnosis based on a single PCR and one to two downstream DNA sequencing reactions. The assay is capable of identifying highly processed shark products including fins, cooked shark fin soup, and skin-care products containing liver oil. This is a straightforward and reliable identification method for data collection and enforcement of regulations implemented for certain species at all governance levels. [ABSTRACT FROM AUTHOR]

There has been an increasing concern about shark overexploitation in the last decade, especially for open ocean shark species, where there is a paucity of data about their life histories and population dynamics. Little is known regarding the population structure of the pelagic thresher shark, Alopias pelagicus. Though an earlier study using mtDNA control region data, showed evidence for differences between eastern and western Pacific populations, the study was hampered by low sample size and sparse geographic coverage, particularly a lack of samples from the central Pacific. Here, we present the population structure of Alopias pelagicus analyzing 351 samples from six different locations across the Pacific Ocean. Using data from mitochondrial DNA COI sequences and seven microsatellite loci we found evidence of strong population differentiation between western and eastern Pacific populations and evidence for reciprocally monophyly for organelle haplotypes and significant divergence of allele frequencies at nuclear loci, suggesting the existence of two Evolutionarily Significant Units (ESU) in the Pacific Ocean. Interestingly, the population in Hawaii appears to be composed of both ESUs in what seems to be clear sympatry with reproductive isolation. These results may indicate the existence of a new cryptic species in the Pacific Ocean. The presence of these distinct ESUs highlights the need for revised management plans for this highly exploited shark throughout its range. [ABSTRACT FROM AUTHOR]

In 2007, the critically endangered European eel (Anguilla anguilla) was listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Flora and Fauna, due to declines in abundance across its range and significant international demand. Illegal trade in live European eel and its products is still occurring to satisfy the high demand around the world. Law enforcement officers face the challenge of identifying both live and processed European eel in a timely fashion to detain shipments and prosecute smugglers. Here, we describe the development of a reliable, field‐based, fast, and cost‐effective real‐time polymerase chain reaction assay to detect European eels in trade. This novel assay was applied in a real law enforcement scenario, where positive results provided enough evidence to detain the shipment for more robust forensic analysis, leading to the first prosecution of eel smuggling in Hong Kong. Our approach could serve as a model for the development of other rapid and cost‐effective tools to detect illegal wildlife trade where visual identification fails to provide enough evidence for prosecution. It could also enhance monitoring and enforcement of laws intended to protect highly traded and threatened species. [ABSTRACT FROM AUTHOR]

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is a multilateral environmental agreement to ensure that the international trade of threatened species is either prohibited (Appendix I listed species) or being conducted legally, sustainably, and transparently (Appendix II listed species). Twelve threatened shark species exploited for their fins, meat, and other products have been listed under CITES Appendix II. Sharks are often traded in high volumes, some of their products are visually indistinguishable, and most importing/exporting nations have limited capacity to detect illicit trade and enforce the regulations. High volume shipments often must be screened after only a short period of detainment (e.g., a maximum of 24 hours), which together with costs and capacity issues have limited the use of DNA approaches to identify illicit trade. Here, we present a reliable, field-based, fast (<4 hours), and cost effective ($0.94 USD per sample) multiplex real-time PCR protocol capable of detecting nine of the twelve sharks listed under CITES in a single reaction. This approach facilitates detection of illicit trade, with positive results providing probable cause to detain shipments for more robust forensic analysis. We also provide evidence of its application in real law enforcement scenarios in Hong Kong. Adoption of this approach can help parties meet their CITES requirements, avoiding potential international trade sanctions in the future. [ABSTRACT FROM AUTHOR]