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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: 4] [Impact Index Per Article: 2.0] [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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Lamperty T, Brosi BJ. Loss of endangered frugivores from seed dispersal networks generates severe mutualism disruption. Proc Biol Sci 2022; 289:20220887. [PMID: 36476005 PMCID: PMC9554716 DOI: 10.1098/rspb.2022.0887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 09/15/2022] [Indexed: 12/14/2022] Open
Abstract
Many tropical seed-dispersing frugivores are facing extinction, but the consequences of the loss of endangered frugivores for seed dispersal is not well understood. We investigated the role of frugivore endangerment status via robustness-to-coextinction simulations (in this context, more accurately described as robustness-to-partner-loss simulations) using data from the Brazilian Atlantic Forest biodiversity hotspot. By simulating the extinction of endangered frugivores, we found a rapid and disproportionate loss of tree species with dispersal partners in the network, and this surprisingly surpassed any other frugivore extinction scenario, including the loss of the most generalist frugivores first. A key driver of this pattern is that many specialist plants rely on at-risk frugivores as seed-dispersal partners. Moreover, interaction compensation in the absence of endangered frugivores may be unlikely because frugivores with growing populations forage on fewer plant species than frugivores with declining populations. Therefore, protecting endangered frugivores could be critical for maintaining tropical forest seed dispersal, and their loss may have higher-than-expected functional consequences for tropical forests, their regeneration processes, and the maintenance of tropical plant diversity.
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Affiliation(s)
- Therese Lamperty
- Department of Biology, University of Washington, Life Sciences Building, 3747 W Stevens WayNE, Seattle, WA 98195, USA
| | - Berry J. Brosi
- Department of Biology, University of Washington, Life Sciences Building, 3747 W Stevens WayNE, Seattle, WA 98195, USA
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Olivares I, Svenning JC, van Bodegom PM, Valencia R, Balslev H. Stability in a changing world - palm community dynamics in the hyperdiverse western Amazon over 17 years. GLOBAL CHANGE BIOLOGY 2017; 23:1232-1239. [PMID: 27614088 DOI: 10.1111/gcb.13494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 08/19/2016] [Accepted: 08/24/2016] [Indexed: 06/06/2023]
Abstract
Are the hyperdiverse local forests of the western Amazon undergoing changes linked to global and local drivers such as climate change, or successional dynamics? We analyzed local climatic records to assess potential climatic changes in Yasuní National Park, Ecuador, and compared two censuses (1995, 2012) of a palm community to assess changes in community structure and composition. Over 17 years, the structure and composition of this palm community remained remarkably stable. Soil humidity was significantly lower and canopy conditions were significantly more open in 2012 compared to 1995, but local climatic records showed that no significant changes in precipitation, temperature or river level have occurred during the last decade. Thus, we found no evidence of recent directional shifts in climate or the palm community in Yasuní. The absence of changes in local climate and plant community dynamics in Yasuní contrasts with recent findings from eastern Amazon, where environmental change is driving significant changes in ecosystem dynamics. Our findings suggest that until now, local forests in the northwest Amazon may have escaped pressure from climate change. The stability of this rich palm community embedded in the hyperdiverse Yasuní National Park underlines its uniqueness as a sanctuary for the protection of Amazonian diversity from global change impacts.
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Affiliation(s)
- Ingrid Olivares
- Section for Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark
| | - Jens-Christian Svenning
- Section for Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark
| | - Peter M van Bodegom
- Institute of Environmental Sciences CML, Leiden University, Einsteinweg 2, 2333 CC, Leiden, The Netherlands
| | - Renato Valencia
- Laboratorio de Ecología de Plantas, Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Av. 12 de Octubre 1076 y Roca, Quito, Ecuador
| | - Henrik Balslev
- Section for Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark
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Harrison RD, Sreekar R, Brodie JF, Brook S, Luskin M, O'Kelly H, Rao M, Scheffers B, Velho N. Impacts of hunting on tropical forests in Southeast Asia. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2016; 30:972-981. [PMID: 27341537 DOI: 10.1111/cobi.12785] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 11/30/2015] [Accepted: 02/01/2016] [Indexed: 06/06/2023]
Abstract
Although deforestation and forest degradation have long been considered the most significant threats to tropical biodiversity, across Southeast Asia (Northeast India, Indochina, Sundaland, Philippines) substantial areas of natural habitat have few wild animals (>1 kg), bar a few hunting-tolerant species. To document hunting impacts on vertebrate populations regionally, we conducted an extensive literature review, including papers in local journals and reports of governmental and nongovernmental agencies. Evidence from multiple sites indicated animal populations declined precipitously across the region since approximately 1980, and many species are now extirpated from substantial portions of their former ranges. Hunting is by far the greatest immediate threat to the survival of most of the region's endangered vertebrates. Causes of recent overhunting include improved access to forests and markets, improved hunting technology, and escalating demand for wild meat, wildlife-derived medicinal products, and wild animals as pets. Although hunters often take common species, such as pigs or rats, for their own consumption, they take rarer species opportunistically and sell surplus meat and commercially valuable products. There is also widespread targeted hunting of high-value species. Consequently, as currently practiced, hunting cannot be considered sustainable anywhere in the region, and in most places enforcement of protected-area and protected-species legislation is weak. The international community's focus on cross-border trade fails to address overexploitation of wildlife because hunting and the sale of wild meat is largely a local issue and most of the harvest is consumed in villages, rural towns, and nearby cities. In addition to improved enforcement, efforts to engage hunters and manage wildlife populations through sustainable hunting practices are urgently needed. Unless there is a step change in efforts to reduce wildlife exploitation to sustainable levels, the region will likely lose most of its iconic species, and many others besides, within the next few years.
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Affiliation(s)
- Rhett D Harrison
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Heilongtan, Kunming, 650201, Yunnan, China.
- World Agroforestry Centre, East & Southern Africa Region, 13 Elm Road, Woodlands, Lusaka, Zambia.
| | - Rachakonda Sreekar
- Xishuangbanna Tropical Botanical Garden, Menglun, Mengla, Yunnan, 666303, China
- School of Biological Sciences, University of Adelaide, SA, 5005, Australia
| | - Jedediah F Brodie
- Departments of Zoology and Botany, University of British Columbia, Vancouver, BC, V6T1Z4, Canada
| | - Sarah Brook
- Wildlife Conservation Society, Cambodia Program, P.O. Box 1620, House 21, Street 21, Phenom Penh, Cambodia
| | - Matthew Luskin
- Department of Environmental Science and Policy, University of California at Berkeley, 130 Mulford Hall, #3114 Berkeley, CA, 94720, U.S.A
| | - Hannah O'Kelly
- Wildlife Conservation Society, Cambodia Program, P.O. Box 1620, House 21, Street 21, Phenom Penh, Cambodia
| | - Madhu Rao
- Wildlife Conservation Society, SE Asia Program, 14 Science Drive 4, 11743, Singapore
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 11743, Singapore
| | - Brett Scheffers
- Department of Wildlife Ecology & Conservation, University of Florida, Gainesville, FL, 32611, U.S.A
| | - Nandini Velho
- Centre for Tropical Environmental and Sustainability Science and College of Marine and Environmental Sciences, James Cook University, Cairns, Qld, 4878, Australia
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