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Parreira F, Palma J, Santos R, Martínez-Crego B. Predation success of declining long-snouted seahorse (Hippocampus guttulatus) population under habitat shifts. MARINE ENVIRONMENTAL RESEARCH 2025; 209:107247. [PMID: 40449212 DOI: 10.1016/j.marenvres.2025.107247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2024] [Revised: 04/25/2025] [Accepted: 05/25/2025] [Indexed: 06/03/2025]
Abstract
Seahorse populations are facing significant declines worldwide, often associated to illegal trade and habitat loss or fragmentation. Emergent habitat shifts towards invasive seaweeds, facilitated by global warming, can also be at play, having still unknown effects on seahorse ecology. Particularly, indirect impacts on seahorse populations via altered predation success remains largely unexplored. Here, we conducted mesocosm experiments to investigate differences in the prey capture success of the long-snouted seahorse (Hippocampus guttulatus) among native habitats (i.e. seagrass meadows and unvegetated sediments) and non-native Caulerpa prolifera meadows when offered different preys (amphipods and shrimps), at low or high prey availability, and under low or high habitat complexity. Great plasticity of H. guttulatus to all habitats was revealed, as habitat type did not significantly affect the capture success. Instead, capture success depends on prey identity and availability regardless of the habitat type, as well as on habitat complexity. Seahorse capture success was higher under high prey availability, as well as when predating on amphipods that were offered together with shrimps. High habitat complexity of both vegetated habitats enhanced by double the capture success, whereas an opposite effect of similar magnitude was found for more complex unvegetated habitats. This indicates that vegetation complexity, regardless their native or invasive nature, reduces prey awareness to predator, whereas small structures in unvegetated habitats provide refuge for preys but not seahorse camouflage. We found no evidence that shifts from native habitats to invasive C. prolifera negatively impact H. guttulatus capture success, but further research on other aspects of its feeding ecology is still necessary.
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Affiliation(s)
- Filipe Parreira
- Centre of Marine Sciences-University of Algarve (CCMAR-UAlg), Campus de Gambelas, 8005-13, Faro, Portugal.
| | - Jorge Palma
- Centre of Marine Sciences-University of Algarve (CCMAR-UAlg), Campus de Gambelas, 8005-13, Faro, Portugal
| | - Rui Santos
- Centre of Marine Sciences-University of Algarve (CCMAR-UAlg), Campus de Gambelas, 8005-13, Faro, Portugal
| | - Begoña Martínez-Crego
- Centre of Marine Sciences-University of Algarve (CCMAR-UAlg), Campus de Gambelas, 8005-13, Faro, Portugal
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Meeks D, Morton O, Edwards DP. Global dynamics of functional composition in CITES-traded reptiles. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2025; 35:e3060. [PMID: 39564741 PMCID: PMC11733411 DOI: 10.1002/eap.3060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 06/04/2024] [Accepted: 09/04/2024] [Indexed: 11/21/2024]
Abstract
Global wildlife trade is a billion-dollar industry, with millions of individuals traded annually from a diversity of taxa, many of which are directly threatened by trade. Reptiles exhibiting desirable life-history or aesthetic traits, such as large body sizes or colorful morphologies, are traded preferentially. A key issue is understanding geographic and temporal variation between desirable species traits and their trade. Poor understanding of this can generalize patterns of consumer trait preferences and conceal functional consequences of wild harvest in ecosystems. Using records of legal, international trade in Convention on International Trade in Endangered Species (CITES)-listed reptiles between 2000 and 2020, we examine geographic and temporal variation in the functional composition of traded assemblages, both captive- and wild-sourced, identifying key hotspots and routes of functional diversity in trade. We also identify associations between functional traits and species presence in trade. We find that functionally diverse trade assemblages are exported primarily from the tropics, with hotspots in sub-Saharan Africa, and imported across Asia, Europe, and North America. Patterns of functional composition in trade remained broadly stable from 2000 to 2020. Globally, the species most likely to be traded were large, fecund, generalists. Sustained wild harvest of functionally diverse reptilian assemblages in trade hotspots, such as Madagascar and Indonesia, places substantial pressure on large-bodied reptiles that fulfill important ecological functions, including population control and nutrient cycling, while also endangering harvest-vulnerable species with slow life histories. Despite limited species-specific descriptions of reptilian ecological functions, management in harvest hotspots can safeguard ecosystem functioning by prioritizing protection for threatened species that contribute disproportionately to local and regional functional diversity.
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Affiliation(s)
- Dominic Meeks
- Ecology and Evolutionary BiologySchool of Biosciences, University of SheffieldSheffieldUK
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
| | - Oscar Morton
- Ecology and Evolutionary BiologySchool of Biosciences, University of SheffieldSheffieldUK
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
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Morton O, Nijman V, Edwards DP. International wildlife trade quotas are characterized by high compliance and coverage but insufficient adaptive management. Nat Ecol Evol 2024; 8:2048-2057. [PMID: 39251819 PMCID: PMC11540902 DOI: 10.1038/s41559-024-02531-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 07/30/2024] [Indexed: 09/11/2024]
Abstract
Effective management of international wildlife trade is crucial to ensure sustainability. Quotas are a common trade management tool and specify an annual number of individuals to be exported, yet at present there is no global assessment of quota coverage and compliance. Using over 7,000 country-year specific reptile quotas established under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) covering 343 species, we quantify quota coverage, compliance, trade trends pre-quota and post-quota setting and whether quotas likely represent adaptive management. Quotas predominantly concerned live wild-sourced reptiles, with only 6.6% of live non-zero quotas exceeded and 4.5% of zero quotas subverted. For 62.3% of species, quotas were established higher than pre-quota trade, with traded volumes post-quota mainly unchanged or higher than pre-quota establishment, thus potentially facilitating sustainable trade. Over 38% of quota series of species remained at the same level each year, with the longest-running quotas proportionately updated the least, indicating that many quotas do not change adaptively in response to changing threats to species through time. Greater specificity in exactly what quotas cover, justification for unchanged quotas and transparency over quota determination are needed to ensure that high compliance equates to sustainable use.
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Affiliation(s)
- Oscar Morton
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, UK.
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, UK.
| | - Vincent Nijman
- Oxford Wildlife Trade Research Group, Oxford Brookes University, Oxford, UK
| | - David P Edwards
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, UK
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Morton O, Nijman V, Edwards DP. Assessing and improving the veracity of international trade in captive-bred animals. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 354:120240. [PMID: 38340671 DOI: 10.1016/j.jenvman.2024.120240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/12/2024]
Abstract
Captive breeding is often seen as a solution to sustainably increasing the supply of individuals in the wildlife trade. To be an effective conservation measure this requires robust systems to verify the authenticity of captive-bred species. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) monitors the international trade in Listed species-which for many taxa is dominated by captive-bred individuals-using the Review of Captive Trade (RCT) process. A key question is how best to identify laundered or inauthentic captive-bred trade and how has this changed over time and space. We develop targeted assessments based on multiple RCT criteria to identify probable instances of laundering and misuse of source and purpose codes in international trade records, and apply this to 39,167 records of captive trade from 2000 to 2020 spanning 53,674,762 individuals. We find a very low proportion of trade volume (1.8%, 37,835 individuals) misreported as originating from non-existent, registered Appendix I-breeding facilities, and low instances of exporter-reported captive trade being recorded by importers as wild-sourced (<4%) or ranched (1%). We also find that <2% of species-year-exporter records have abrupt shifts from wild to captive sources, potentially indicating laundering. Conversely, we find high incidences of exporter- and importer-reported trade differing in whether the trade was commercial or not - a phenomenon we attribute to differing definitions, not illegal activity. Our results indicate a low incidence of concerning international trade being reported, but we suggest this likely stems from reporting requirements that limit our assessments. We highlight additional trade data that, if embedded into Party's annual reports, would vastly improve inferential potential, greatly increasing the number of records (Appendix II and III species) that could be verified with minimal effort for management authorities.
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Affiliation(s)
- Oscar Morton
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK; Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3EA, UK.
| | - Vincent Nijman
- Oxford Wildlife Trade Research Group, Oxford Brookes University, Oxford, OX3 0BP, UK.
| | - David P Edwards
- Department of Plant Sciences and Conservation Research Institute, University of Cambridge, Cambridge, CB2 3EA, UK
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Scheffers BR. Species risk assessment informs trade regulation. Nat Ecol Evol 2023; 7:1175-1176. [PMID: 37414948 DOI: 10.1038/s41559-023-02097-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Affiliation(s)
- Brett R Scheffers
- Department of Wildlife Ecology and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, USA.
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Hughes A, Auliya M, Altherr S, Scheffers B, Janssen J, Nijman V, Shepherd CR, D'Cruze N, Sy E, Edwards DP. Determining the sustainability of legal wildlife trade. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 341:117987. [PMID: 37178541 DOI: 10.1016/j.jenvman.2023.117987] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/19/2023] [Accepted: 04/18/2023] [Indexed: 05/15/2023]
Abstract
Exploitation of wildlife represents one of the greatest threats to species survival according to the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Whilst detrimental impacts of illegal trade are well recognised, legal trade is often equated to being sustainable despite the lack of evidence or data in the majority of cases. We review the sustainability of wildlife trade, the adequacy of tools, safeguards, and frameworks to understand and regulate trade, and identify gaps in data that undermine our ability to truly understand the sustainability of trade. We provide 183 examples showing unsustainable trade in a broad range of taxonomic groups. In most cases, neither illegal nor legal trade are supported by rigorous evidence of sustainability, with the lack of data on export levels and population monitoring data precluding true assessments of species or population-level impacts. We propose a more precautionary approach to wildlife trade and monitoring that requires those who profit from trade to provide proof of sustainability. We then identify four core areas that must be strengthened to achieve this goal: (1) rigorous data collection and analyses of populations; (2) linking trade quotas to IUCN and international accords; (3) improved databases and compliance of trade; and (4) enhanced understanding of trade bans, market forces, and species substitutions. Enacting these core areas in regulatory frameworks, including CITES, is essential to the continued survival of many threatened species. There are no winners from unsustainable collection and trade: without sustainable management not only will species or populations become extinct, but communities dependent upon these species will lose livelihoods.
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Affiliation(s)
- Alice Hughes
- School of Biological Sciences, University of Hong Kong, China.
| | - Mark Auliya
- Department of Herpetology, Leibniz Institute for the Analysis of Biodiversity Change, Zoological Research Museum Alexander Koenig, Bonn, Germany
| | | | - Brett Scheffers
- Department of Wildlife Ecology and Conservation, University of Florida/IFAS, Gainesville, FL, USA
| | - Jordi Janssen
- Monitor Conservation Research Society, PO BOX 200, Big Lake Ranch, BC, V0L 1G0, Canada
| | - Vincent Nijman
- Oxford Wildlife Trade Research Group, Oxford Brookes University, Oxford, OX3 0BP, UK.
| | - Chris R Shepherd
- Monitor Conservation Research Society, PO BOX 200, Big Lake Ranch, BC, V0L 1G0, Canada
| | - Neil D'Cruze
- The Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Tubney, UK; World Animal Protection, 222 Greys Inn Road, London, WC1X 8HB, UK
| | - Emerson Sy
- Philippine Center for Terrestrial & Aquatic Research, Manila, Philippines
| | - David P Edwards
- Ecology and Evolutionary Biology, School of Biosciences University of Sheffield, Sheffield, S10 2TN, UK.
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Hughes LJ, Morton O, Scheffers BR, Edwards DP. The ecological drivers and consequences of wildlife trade. Biol Rev Camb Philos Soc 2022; 98:775-791. [PMID: 36572536 DOI: 10.1111/brv.12929] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/11/2022] [Accepted: 12/14/2022] [Indexed: 12/28/2022]
Abstract
Wildlife trade is a key driver of extinction risk, affecting at least 24% of terrestrial vertebrates. The persistent removal of species can have profound impacts on species extinction risk and selection within populations. We draw together the first review of characteristics known to drive species use - identifying species with larger body sizes, greater abundance, increased rarity or certain morphological traits valued by consumers as being particularly prevalent in trade. We then review the ecological implications of this trade-driven selection, revealing direct effects of trade on natural selection and populations for traded species, which includes selection against desirable traits. Additionally, there exists a positive feedback loop between rarity and trade and depleted populations tend to have easy human access points, which can result in species being harvested to extinction and has the potential to alter source-sink dynamics. Wider cascading ecosystem repercussions from trade-induced declines include altered seed dispersal networks, trophic cascades, long-term compositional changes in plant communities, altered forest carbon stocks, and the introduction of harmful invasive species. Because it occurs across multiple scales with diverse drivers, wildlife trade requires multi-faceted conservation actions to maintain biodiversity and ecological function, including regulatory and enforcement approaches, bottom-up and community-based interventions, captive breeding or wildlife farming, and conservation translocations and trophic rewilding. We highlight three emergent research themes at the intersection of trade and community ecology: (1) functional impacts of trade; (2) altered provisioning of ecosystem services; and (3) prevalence of trade-dispersed diseases. Outside of the primary objective that exploitation is sustainable for traded species, we must urgently incorporate consideration of the broader consequences for other species and ecosystem processes when quantifying sustainability.
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Affiliation(s)
- Liam J. Hughes
- Ecology and Evolutionary Biology School of Biosciences, University of Sheffield South Yorks S10 2TN Sheffield UK
| | - Oscar Morton
- Ecology and Evolutionary Biology School of Biosciences, University of Sheffield South Yorks S10 2TN Sheffield UK
| | - Brett R. Scheffers
- Department of Wildlife Ecology and Conservation Institute of Food and Agricultural Sciences, University of Florida Gainesville FL 32611 USA
| | - David P. Edwards
- Ecology and Evolutionary Biology School of Biosciences, University of Sheffield South Yorks S10 2TN Sheffield UK
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Green J, Schmidt-Burbach J, Elwin A. Commercial trade of wild animals: examining the use of the IUCN Red List and CITES Appendices as the basis for corporate trade policies. FRONTIERS IN CONSERVATION SCIENCE 2022. [DOI: 10.3389/fcosc.2022.902074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Wildlife exploitation is considered a predominant factor driving global biodiversity loss and zoonotic disease transmission, in addition to a range of concerns for animal welfare and ecosystem health. One of the ways in which wild animals are exploited is for commercial trade as exotic pets, fashion products, luxury foods, traditional medicine, entertainment, ornaments and more. While the trade in some wildlife species is restricted or prohibited under various domestic and international laws, many species are not bound by legal protection and are traded in largely unmonitored numbers with the potential for severe consequences. Companies, particularly large e-commerce platforms, are increasingly adopting policies to restrict the legal trade in wild animals. Due to the absence of clear guidelines for corporate services of wildlife trade, these policies commonly adopt pre-determined species lists, such as the International Union for the Conservation of Nature’s (IUCN) Red List of Threatened Species or the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendices, as the basis for ‘negative lists’ to guide which species to restrict trade in. However, these databases were not intended for this application and there has been no assessment of their use for this purpose. Here, we summarise and compare the scale and scope of species listed on the IUCN Red List and the CITES Appendices, to discuss how much additional protection these lists provide wild animals if used as policy instruments to guide corporate wildlife trade restrictions beyond the relevant legal bounds. Based on our results, we discuss why that using one list or another would likely omit taxa of conservation concern from protection, and using both lists in conjunction would still not comprehensively reflect all species vulnerable to extinction as a result of exploitation. Further, neither list can mitigate the animal welfare and public health concerns inherently associated with all commercial wildlife trade. We recommend that companies looking to develop policies relating to commercial wildlife trade consider going beyond the scope of predetermined species lists to help mitigate the harmful effects of commercial wildlife exploitation via trade for all wild animals.
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Wilcove DS. Conservation: Trading species to extinction? Curr Biol 2022; 32:R313-R315. [PMID: 35413256 DOI: 10.1016/j.cub.2022.02.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Is the Convention on International Trade in Endangered Species (CITES) up to the task of preventing species from being driven to extinction by trade? A new study documents some success but also highlights major deficiencies.
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Affiliation(s)
- David S Wilcove
- School of Public and International Affairs and Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.
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