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1.
PLoS Biol ; 21(1): e3001946, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36719873

RESUMO

Large carnivores have long fascinated human societies and have profound influences on ecosystems. However, their conservation represents one of the greatest challenges of our time, particularly where attacks on humans occur. Where human recreational and/or livelihood activities overlap with large carnivore ranges, conflicts can become particularly serious. Two different scenarios are responsible for such overlap: In some regions of the world, increasing human populations lead to extended encroachment into large carnivore ranges, which are subject to increasing contraction, fragmentation, and degradation. In other regions, human and large carnivore populations are expanding, thus exacerbating conflicts, especially in those areas where these species were extirpated and are now returning. We thus face the problem of learning how to live with species that can pose serious threats to humans. We collected a total of 5,440 large carnivore (Felidae, Canidae, and Ursidae; 12 species) attacks worldwide between 1950 and 2019. The number of reported attacks increased over time, especially in lower-income countries. Most attacks (68%) resulted in human injuries, whereas 32% were fatal. Although attack scenarios varied greatly within and among species, as well as in different areas of the world, factors triggering large carnivore attacks on humans largely depend on the socioeconomic context, with people being at risk mainly during recreational activities in high-income countries and during livelihood activities in low-income countries. The specific combination of local socioeconomic and ecological factors is thus a risky mix triggering large carnivore attacks on humans, whose circumstances and frequencies cannot only be ascribed to the animal species. This also implies that effective measures to reduce large carnivore attacks must also consider the diverse local ecological and social contexts.


Assuntos
Canidae , Carnívoros , Ursidae , Animais , Humanos , Ecossistema , Conservação dos Recursos Naturais/métodos
2.
Sci Rep ; 11(1): 22808, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815416

RESUMO

Conservation of carnivores involves finding solutions to minimize habitat loss and human-wildlife conflict. Understanding the nature of land-use economics can allow us to mitigate both threats. In the Pantanal, the two main economic activities are cattle ranching and ecotourism, each of which directly and indirectly affect the persistence of jaguars (Panthera onca). To understand how the geography of these economic activities is related to jaguar populations, we developed a jaguar distribution model (JDM), livestock density model, and ecotourism lodge density model for the Pantanal. Due to the recent wildfires within the Pantanal, we also assess the impact of burnt areas that are suitable for jaguars, cattle ranching, and tourism. Our JDM indicate that 64% of the Pantanal holds suitable habitat for jaguars. However, jaguar habitat suitability was positively correlated with ecotourism, but negatively correlated with areas most suitable for intensive cattle-ranching. This demonstrates a biome-wide scenario compatible with jaguar conservation. Of particular concern, recent wildfires overlap most suitable areas for jaguars. If wildfires become increasingly frequent, this would represent a serious threat to jaguars and many other wildlife populations. We emphasize the global importance of the Pantanal wetland ecoregion as a key stronghold for long-term jaguar conservation.


Assuntos
Conservação dos Recursos Naturais/economia , Ecossistema , Panthera/fisiologia , Dinâmica Populacional , Turismo , Urbanização/tendências , Áreas Alagadas , Animais , Bovinos , Geografia
3.
Curr Biol ; 31(15): 3457-3466.e4, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34237270

RESUMO

Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function.1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.


Assuntos
Efeitos Antropogênicos , Atividade Motora , Panthera , Comportamento Espacial , Animais , Conservação dos Recursos Naturais , Ecologia , Ecossistema , Masculino
4.
Pesqui. vet. bras ; 38(12): 2266-2277, dez. 2018. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-976417

RESUMO

Em diversas partes da América Latina, a perda e diminuição do habitat natural de animais silvestres ocorre em função do aumento das atividades agropecuárias. Nos últimos anos o número de mortes de animais de criação por depredação tem aumentado, bem como a consequente retaliação aos predadores. Como resultado destas ações, ocorre à extinção ou redução das populações destes predadores de topo, provocando perdas ecológicas. Esse estudo teve como objetivo apontar medidas preventivas e mitigatórias da depredação de ovinos por onça-parda (Puma concolor). Através da análise de dois estudos de casos de depredação no Centro-Oeste brasileiro e na região dos Andes Colombianos, levantamos soluções alternativas sustentáveis para que profissionais e criadores possam se prevenir desta ameaça ao rebanho ovino. Um estudo de caso foi realizado em fazenda no município de Alto Paraguai, Mato Grosso. Entre os anos 2005 e 2014 houve visitas na propriedade para diagnóstico de doenças e realizou-se estudo comparativo da quantidade de mortes por doenças com as mortes por depredação. No ano de 2010 ocorreu um ataque depredatório que resultou em morte de seis ovinos. Em 2014, realizou-se um estudo na região central do Departamento del Valle del Cauca, há 2814m de altitude nos Andes colombianos, para diagnosticar a depredação de gado na região e implementar medidas para prevenir sua ocorrência e avaliar sua eficácia. No total, foram implementadas medidas anti-depredação sobre oito propriedades, e entre elas, um curral com cerca elétrica para ovelhas foi implementada em uma fazenda no município de Tuluá. Os resultados mostram que as perdas econômicas por depredação são graves nas duas regiões estudadas e se equiparam a perdas por doenças no estudo de caso em Mato Grosso, Brasil. Portanto recomenda-se a combinação entre o manejo sanitário, métodos de prevenção e, se necessário, mitigação de ataques depredatório. Além disso, legisladores devem se associar a pesquisadores para traçar estratégias efetivas para esse sério problema na América Latina.(AU)


In several parts of Latin America, the expansion of agriculture over the years has caused loss and reduction of wild fauna natural habitat. Recently, deaths of sheep and cattle have increased due to predation by large carnivores and the resulting retaliation by farmers on predators. Consequently, populations of these top predators have been reduced or have got even locally extinct, leading to imbalances on ecosystems, altered because of the carnivore effects on prey dinamics. The objective of this study is to analyse sheep depredation by puma (Puma concolor), in Central Brazil and in the Colombian Andes and point out preventive and mitigating measures that can be implemented in rural areas. From 2005 to 2014, we visited a ranch in Alto Paraguai, Mato Grosso, Brazil for diagnostic purposes and we compared the death of sheep from diseases and depredation attacks. In 2014, we visited a rural area in the central region of Departamento del Valle del Cauca, at 2814m of altitude in the Colombian Andes, to diagnose sheep predation, implement preventive measures, and evaluate their effectiveness. The results reveal that economic losses due to predation are critical on both studied regions and similar to losses by diseases in Mato Grosso state, Brazil. Thus, we recommend the integration of health management, preventive measures as well as mitigation of depredatory attacks at the local scale and we discuss potential sustainable measures that can be locally implemented by farmers. Furthermore, we recommend that public policies should incorporate scientific results on human-wildlife conflicts to be effective, considering both livestock management and biodiversity conservation.(AU)


Assuntos
Animais , Ovinos , Conservação dos Recursos Naturais , Puma , Criação de Animais Domésticos , Espécies em Perigo de Extinção , Política Ambiental , Animais Selvagens
5.
Ecology ; 99(7): 1691, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29961270

RESUMO

The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation-scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species' distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human-modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator-prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long-term conservation efforts for this ecologically important species. There are no costs, copyright, or proprietary restrictions associated with this data set. When using this data set, please cite this article to recognize the effort involved in gathering and collating the data and the willingness of the authors to make it publicly available.


Assuntos
Panthera , Animais , Ecologia , Feminino , Humanos , Masculino , Movimento
6.
PLoS One ; 13(3): e0194719, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29579129

RESUMO

Broad scale population estimates of declining species are desired for conservation efforts. However, for many secretive species including large carnivores, such estimates are often difficult. Based on published density estimates obtained through camera trapping, presence/absence data, and globally available predictive variables derived from satellite imagery, we modelled density and occurrence of a large carnivore, the jaguar, across the species' entire range. We then combined these models in a hierarchical framework to estimate the total population. Our models indicate that potential jaguar density is best predicted by measures of primary productivity, with the highest densities in the most productive tropical habitats and a clear declining gradient with distance from the equator. Jaguar distribution, in contrast, is determined by the combined effects of human impacts and environmental factors: probability of jaguar occurrence increased with forest cover, mean temperature, and annual precipitation and declined with increases in human foot print index and human density. Probability of occurrence was also significantly higher for protected areas than outside of them. We estimated the world's jaguar population at 173,000 (95% CI: 138,000-208,000) individuals, mostly concentrated in the Amazon Basin; elsewhere, populations tend to be small and fragmented. The high number of jaguars results from the large total area still occupied (almost 9 million km2) and low human densities (< 1 person/km2) coinciding with high primary productivity in the core area of jaguar range. Our results show the importance of protected areas for jaguar persistence. We conclude that combining modelling of density and distribution can reveal ecological patterns and processes at global scales, can provide robust estimates for use in species assessments, and can guide broad-scale conservation actions.


Assuntos
Panthera/fisiologia , Animais , Conservação dos Recursos Naturais , Ecossistema , Modelos Teóricos , Densidade Demográfica
7.
An Acad Bras Cienc ; 90(2 suppl 1): 2129-2139, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28832728

RESUMO

The Pantanal is the largest inland wetland in the world and is under increasing anthropogenic threats, including long-term regionally intensive gold mining practices. Gold mining activities are known to cause the release of harmful pollutants such as mercury (Hg) to the surrounding environment. Jaguars (Panthera onca (Linnaeus, 1758)) are apex predators, and therefore show great potential to accumulate Hg by biomagnification. We hypothesize that total Hg content in the fur of jaguars from two sites within the Brazilian Pantanal would be significantly different as a function of distance from active gold mining operations. The Hg content was determined by fluorescence spectrometry. The mean ± SD Hg content in jaguars from the study site influenced by gold mining (SB) was compared to jaguars sampled in the area free of gold mining activities (CA) using a one-way ANOVA. The mean Hg content in jaguars from SB (673.0 ± 916.8 µg g-1) is significantly different from jaguars sampled in CA (29.7 ± 23.3 µg g-1), p = 0.03. The maximum recorded content of Hg was 2,010.4 ± 150.5 µg g-1, highest level ever recorded in a wild animal. The data indicate that Hg is an important threat to jaguars within at-risk regions of the Pantanal.

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