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1.
Conserv Biol ; 38(5): e14334, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39248774

RESUMO

Globally, illegal sport hunting can threaten prey populations when unregulated. Due to its covert nature, illegal sport hunting poses challenges for data collection, hindering efforts to understand the full extent of its impacts. We gathered social media data to analyze patterns of illegal sport hunting and wildlife depletion across Brazil. We collected data for 2 years (2018-2020) across 5 Facebook groups containing posts depicting pictures of illegal sport hunting events of native fauna. We described and mapped these hunting events by detailing the number of hunters involved, the number of species, the mean body mass of individuals, and the number and biomass of individuals hunted per unit area, stratified by Brazilian biome. We also examined the effects of defaunation on hunting yield and composition via regression models, rank-abundance curves, and spatial interpolation. We detected 2046 illegal sport hunting posts portraying the hunting of 4658 animals (∼29 t of undressed meat) across all 27 states and 6 natural biomes of Brazil. Of 157 native species targeted by hunters, 19 are currently threatened with extinction. We estimated that 1414 hunters extracted 3251 kg/million km2. Some areas exhibited more pronounced wildlife depletion, in particular the Atlantic Forest and Caatinga biomes. In these areas, there was a shift from large mammals and reptiles to small birds as the main targeted taxa, and biomass extracted per hunting event and mean body mass across all taxonomic groups were lower than in other areas. Our results highlight that illegal sport hunting adds to the pressures of subsistence hunting and the wild meat trade on Brazil's wildlife populations. Enhanced surveillance efforts are needed to reduce illegal sport hunting levels and to develop well-managed sustainable sport hunting programs. These can support wildlife conservation and offer incentives for local communities to oversee designated sport hunting areas.


Exposición de la caza ilegal y la reducción de fauna en el país tropical más grande del mundo por medio de datos de las redes sociales Resumen En todo el mundo, la caza recreativa ilegal puede amenazar a las poblaciones de presas cuando no está regulada. Debido a su naturaleza encubierta, la caza recreativa ilegal plantea dificultades para la recopilación de datos, lo que dificulta la comprensión de su impacto. Recopilamos datos de redes sociales para analizar los patrones de caza recreativa ilegal y agotamiento de la vida silvestre en todo Brasil. Recopilamos datos durante 2 años (2018­2020) a través de cinco grupos de Facebook que contenían publicaciones que mostraban imágenes de eventos de caza recreativa ilegal de fauna nativa. Describimos y mapeamos estos eventos de caza detallando el número de cazadores involucrados, el número de especies, la masa corporal media de los individuos y el número y la biomasa de los individuos cazados por unidad de área, estratificados por bioma brasileño. También examinamos los efectos de la deforestación en el rendimiento y la composición de la caza mediante modelos de regresión, curvas de abundancia e interpolación espacial. Detectamos 2,046 puestos de caza recreativa ilegal que mostraban la caza de 4,658 animales (∼29 t de carne sin desollar) en los 27 estados y 6 biomas naturales de Brasil. De las 157 especies autóctonas objetivo de los cazadores, 18 están actualmente en peligro de extinción. Se calcula que 1,414 cazadores extrajeron 3,251 kg/millón de km2. Algunas zonas mostraron una defaunación más pronunciada, en particular los biomas de la Mata Atlántica y la Caatinga. En estas áreas, se produjo un cambio de grandes mamíferos y reptiles a pequeñas aves como principales taxones objetivo, y la biomasa extraída por evento de caza y la masa corporal media en todos los grupos taxonómicos fueron menores que en otras áreas. Nuestros resultados ponen de manifiesto que la caza recreativa ilegal se suma a las presiones de la caza de subsistencia y el comercio de carne salvaje sobre las poblaciones de fauna de Brasil. Es necesario intensificar los esfuerzos de vigilancia para reducir los niveles de caza recreativa ilegal y desarrollar programas de caza recreativa sostenibles y bien gestionados. Estos programas pueden contribuir a la conservación de la fauna y ofrecer incentivos a las comunidades locales para que supervisen las zonas designadas para la caza recreativa.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Caça , Mídias Sociais , Conservação dos Recursos Naturais/legislação & jurisprudência , Brasil , Animais , Esportes/legislação & jurisprudência , Humanos
2.
Nature ; 520(7545): 45-50, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25832402

RESUMO

Human activities, especially conversion and degradation of habitats, are causing global biodiversity declines. How local ecological assemblages are responding is less clear--a concern given their importance for many ecosystem functions and services. We analysed a terrestrial assemblage database of unprecedented geographic and taxonomic coverage to quantify local biodiversity responses to land use and related changes. Here we show that in the worst-affected habitats, these pressures reduce within-sample species richness by an average of 76.5%, total abundance by 39.5% and rarefaction-based richness by 40.3%. We estimate that, globally, these pressures have already slightly reduced average within-sample richness (by 13.6%), total abundance (10.7%) and rarefaction-based richness (8.1%), with changes showing marked spatial variation. Rapid further losses are predicted under a business-as-usual land-use scenario; within-sample richness is projected to fall by a further 3.4% globally by 2100, with losses concentrated in biodiverse but economically poor countries. Strong mitigation can deliver much more positive biodiversity changes (up to a 1.9% average increase) that are less strongly related to countries' socioeconomic status.


Assuntos
Biodiversidade , Atividades Humanas , Animais , Conservação dos Recursos Naturais/tendências , Ecologia/tendências , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Modelos Biológicos , Dinâmica Populacional , Especificidade da Espécie
3.
Biol Conserv ; 264: 109365, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34975159

RESUMO

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) prohibits commercial trans-national trade in pangolin specimens. However, African pangolins are continually trafficked to Asia for traditional medicine, with Nigeria considered a key hub. Using reported Nigeria-linked pangolin seizure data and interviews with Nigerian law enforcement officials, we a) characterised Nigeria's involvement in global pangolin trafficking January 2010-September 2021, particularly observing trafficking trends after pangolin's CITES Appendix I listing; b) estimated the minimum number of pangolins whose scales are in Nigeria-linked seizures January 2010-September 2021, and; c) assessed ongoing efforts within Nigeria to curb pangolin trafficking. Nigeria-linked seizures involved 190,407 kg of pangolin derivatives (99.9% scales) from a minimum of 799,343 pangolins (95% confidence interval; 625,944-996,353) of four species (see caveats in Methods). All shipments confiscated in transit were destined for Asia, with a rapid increase in the mass of maritime shipments over time. Furthermore, stockpiling of pangolin derivatives for overseas shipment is perhaps a prominent trafficking model in Nigeria. Nigeria's law enforcement efforts improved from 2017, the same year Nigeria apparently began playing a hub role. The impact of pangolin's CITES Appendix I listing on pangolin trafficking was unclear, as the marked rise in seizures from 2017 when the listing became effective, coincided with improvements in Nigerian law enforcement efforts. COVID-19-induced travel restrictions likely reduced trafficking activities in 2020 but activities may have fully resumed in 2021. This study provides new information to inform effective enforcement and policy formulation efforts to protect African pangolins.

4.
Ecol Evol ; 13(5)2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37181204

RESUMO

Pangolin species are notoriously difficult to detect and monitor in the wild and, as a result, commonly used survey techniques fall short in gathering sufficient data to draw confident conclusions on pangolin populations, conservation status, and natural history. The white-bellied pangolin is a semiarboreal species that may be poorly detected in general mammal surveys even with modern techniques such as camera-trapping. As a result, population status information is often derived from hunting, market, and trafficking data. There is therefore a crucial need to improve camera-trap survey methods to reliably detect this species in its natural environment. Here, we test the influence of camera-trap placement strategy on the detectability of the white-bellied pangolin by comparing estimates from targeted ground-viewing camera-trapping and a novel log-viewing placement strategy adapted from local hunters' knowledge. Our results suggest that (1) deploying camera-traps to detect animals walking along logs is an effective strategy for recording several forest species, including the white-bellied pangolin, and (2) that camera-traps targeting logs are more efficient at detecting white-bellied pangolins than camera-traps viewing the ground (>100% increase in detection probability). We also found moderate evidence that there is a relationship between the white-bellied pangolin occurrence at our locality and elevation and weak evidence of an association with distance to the nearest river. Our results suggest an effective new monitoring approach allowing consistent detection of the white-bellied pangolin with moderate survey effort. This highlights the importance of harnessing local knowledge to guide the design of monitoring protocols for cryptic species.

5.
Trends Ecol Evol ; 36(3): 216-226, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33293193

RESUMO

Given the failure of the world's governments to improve the status of biodiversity by 2020, a new strategic plan for 2030 is being developed. In order to be successful, a step-change is needed to not just simply halt biodiversity loss, but to bend the curve of biodiversity loss to stable or increasing species' populations. Here, we propose a framework that quantifies species' responses across gradients of threat intensity to implement more efficient and better targeted conservation actions. Our framework acknowledges the variation in threat intensities as well as the differences among species in their capacity to respond, and is implemented at a relevant scale for national and international policy-making.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais
6.
UCL Open Environ ; 1: e002, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-37228249

RESUMO

Maintaining biodiversity is crucial for ensuring human well-being. The authors participated in a workshop held in Palenque, Mexico, in August 2018, that brought together 30 mostly early-career scientists working in different disciplines (natural, social and economic sciences) with the aim of identifying research priorities for studying the contributions of biodiversity to people and how these contributions might be impacted by environmental change. Five main groups of questions emerged: (1) Enhancing the quantity, quality, and availability of biodiversity data; (2) Integrating different knowledge systems; (3) Improved methods for integrating diverse data; (4) Fundamental questions in ecology and evolution; and (5) Multi-level governance across boundaries. We discuss the need for increased capacity building and investment in research programmes to address these challenges.

7.
Ecohealth ; 14(2): 361-388, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28332127

RESUMO

The overhunting of wildlife for food and commercial gain presents a major threat to biodiversity in tropical forests and poses health risks to humans from contact with wild animals. Using a recent survey of wildlife offered at wild meat markets in Malaysia as a basis, we review the literature to determine the potential zoonotic infection risks from hunting, butchering and consuming the species offered. We also determine which taxa potentially host the highest number of pathogens and discuss the significant disease risks from traded wildlife, considering how cultural practices influence zoonotic transmission. We identify 51 zoonotic pathogens (16 viruses, 19 bacteria and 16 parasites) potentially hosted by wildlife and describe the human health risks. The Suidae and the Cervidae families potentially host the highest number of pathogens. We conclude that there are substantial gaps in our knowledge of zoonotic pathogens and recommend performing microbial food safety risk assessments to assess the hazards of wild meat consumption. Overall, there may be considerable zoonotic risks to people involved in the hunting, butchering or consumption of wild meat in Southeast Asia, and these should be considered in public health strategies.


Assuntos
Animais Selvagens , Carne , Suínos , Zoonoses , Animais , Doenças Transmissíveis , Humanos , Malásia
9.
Ecol Evol ; 7(1): 145-188, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28070282

RESUMO

The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

10.
Ecol Evol ; 4(24): 4701-35, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25558364

RESUMO

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - http://www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.

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