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1.
PLoS One ; 19(5): e0299783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748670

RESUMO

Unsustainable trade in big cats affects all species in the genus, Panthera, and is one of the foremost threats to their conservation. To provide further insight into the impact of policy interventions intended to address this issue, we examine the case study of the Republic of Korea (South Korea), which in the early 1990s was one of the world's largest importers of tiger (Panthera tigris) bone and a major manufacturer of tiger-derived medicinal products. In 1993, South Korea became a Party to the Convention on International Trade in Endangered Species (CITES) and introduced a ban on commercial trade in CITES Appendix I-listed big cats a year later. We used an expert-based questionnaire survey and an exploration of the CITES trade database to investigate what has since happened to big cat trade in South Korea. Expert opinion suggested that big cat trade has likely substantially reduced since the early 1990s, as a result of the trade ban and broad socioeconomic changes. However, illegal trade has not been eradicated entirely and we were able to confirm that products reportedly derived from big cats were still publicly available for sale on a range of Korean online marketplaces, sometimes openly. The items most commonly reported by respondents from post-1994 trade and supported by expert-led evidence were tiger and leopard (Panthera pardus) skins and tiger bone wine. Although South Korea may provide a useful case study of a historically significant consumer country for tiger which has made strong progress in addressing unsustainable levels of big cat trade within a short period of time, there remains a need to address recalcitrant small-scale, illegal trade. We also recommend further investigation regarding reports of South Korean nationals being involved in illegal trade in tiger-derived products in Southeast Asia.


Assuntos
Comércio , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , República da Coreia , Animais , Comércio/tendências , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/tendências , Espécies em Perigo de Extinção/legislação & jurisprudência , Espécies em Perigo de Extinção/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Tigres , Panthera , Inquéritos e Questionários , Gatos
3.
Trends Ecol Evol ; 36(1): 29-38, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33020018

RESUMO

Climate change and land use change often interact, altering biodiversity in unexpected ways. Research into climate change-land use change (CC-LUC) interactions has so far focused on quantifying biodiversity outcomes, rather than identifying the underlying ecological mechanisms, making it difficult to predict interactions and design appropriate conservation responses. We propose a risk-based framework to further our understanding of CC-LUC interactions. By identifying the factors driving the exposure and vulnerability of biodiversity to land use change, and then examining how these factors are altered by climate change (or vice versa), this framework will allow the effects of different interaction mechanisms to be compared across geographic and ecological contexts, supporting efforts to reduce biodiversity loss from interacting stressors.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema
4.
Ecol Evol ; 10(13): 6769-6774, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32724549

RESUMO

Carrion represents an unpredictable and widely distributed primary food source for vultures and other avian scavengers. Avian scavengers in African savanna ecosystems are reported to rely exclusively on visual stimuli to locate carcasses. However, carnivores' predation of large mammalian herbivores and subsequent competition for access to the carcass can result in considerable noise, often audible over long distances and for prolonged periods. Vultures and other avian scavengers may therefore detect and respond to these auditory cues, as do the mammalian carnivores alongside which vultures have coevolved, but this has not been investigated to date. Working in the Serengeti ecosystem, Tanzania, we used diurnal auditory broadcasts to simulate predation and competitive carnivore feeding interactions. Based on the current understanding of avian scavenger ecology, we hypothesized that avian responses to call-in stations would be evoked exclusively by visual, rather than auditory, cues. We therefore predicted that (a) the arrival of avian scavengers at call-in stations should be preceded and facilitated by mammalian carnivores and that (b) the arrival of avian scavengers would be positively correlated with the number of mammalian scavengers present, which would increase detectability. We recorded 482 birds during 122 separate playback events. In 22% of these instances, avian scavengers arrived first, ruling out responses based exclusively on visual observations of mammalian carnivores, thereby contradicting our first prediction. Furthermore, the first avian arrivals at survey sessions were inversely related to the number of hyenas and jackals present, contradicting our second prediction. Since no bait or carcasses were used during the experiments, these responses are indicative of the birds' ability to detect and respond to audio stimuli. Our findings challenge the current consensus of sensory perception and foraging in these species and provide evidence that avian scavengers have the ability to use sound to locate food resources.

6.
Philos Trans R Soc Lond B Biol Sci ; 374(1781): 20190011, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31352894

RESUMO

Effective conservation management is underpinned by science. Yet, there are often barriers against the incorporation of up-to-date scientific research into decision-making and policy. Here, we draw on experience from a multi-nation approach to conserve cheetah and African wild dogs across Africa, using relationships between scientists and managers established over more than a decade, to better understand scientific information needs of managers. While our analysis focuses on Africa, many of our findings are likely to be relevant to other regions. Managers view science as critical to their decision-making processes and strongly support scientific research, particularly when research directly addresses their information needs. However, managers reported problems in accessing final results and highlighted the need to access raw ecological data from research undertaken within protected areas. Fundamental to improving the management relevance of scientific research is the need for scientists to engage with managers through all steps of the research process, from project design and implementation through to scientific publication and end-of-project agreements. Effective engagement requires open and clear communication; including agreed processes for access to biodiversity data and submission of final results. In order to foster future scientific endeavours and collaborations, systems should be established to better facilitate information exchange, while also safeguarding the rights of scientists to publish their data and protect their academic freedom. Our analysis also calls for a greater awareness of the geo-political context under which science is undertaken, and for increased scientific participation through an inclusive approach that recognizes, and gives credit to, a wider diversity of scientific contributions and expertise. This article is part of the theme issue 'Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.


Assuntos
Acinonyx , Canidae , Conservação dos Recursos Naturais/métodos , Tomada de Decisões , Disseminação de Informação/métodos , África , Animais , Conservação dos Recursos Naturais/legislação & jurisprudência , Política Pública
7.
Proc Natl Acad Sci U S A ; 114(3): 528-533, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28028225

RESUMO

Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes.


Assuntos
Acinonyx , Conservação dos Recursos Naturais , África , Animais , Ásia , Biodiversidade , Simulação por Computador , Extinção Biológica , Modelos Biológicos , Dinâmica Populacional/tendências , Fatores de Risco
8.
PeerJ ; 4: e1974, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27168983

RESUMO

The leopard's (Panthera pardus) broad geographic range, remarkable adaptability, and secretive nature have contributed to a misconception that this species might not be severely threatened across its range. We find that not only are several subspecies and regional populations critically endangered but also the overall range loss is greater than the average for terrestrial large carnivores. To assess the leopard's status, we compile 6,000 records at 2,500 locations from over 1,300 sources on its historic (post 1750) and current distribution. We map the species across Africa and Asia, delineating areas where the species is confirmed present, is possibly present, is possibly extinct or is almost certainly extinct. The leopard now occupies 25-37% of its historic range, but this obscures important differences between subspecies. Of the nine recognized subspecies, three (P. p. pardus, fusca, and saxicolor) account for 97% of the leopard's extant range while another three (P. p. orientalis, nimr, and japonensis) have each lost as much as 98% of their historic range. Isolation, small patch sizes, and few remaining patches further threaten the six subspecies that each have less than 100,000 km(2) of extant range. Approximately 17% of extant leopard range is protected, although some endangered subspecies have far less. We found that while leopard research was increasing, research effort was primarily on the subspecies with the most remaining range whereas subspecies that are most in need of urgent attention were neglected.

11.
PLoS One ; 10(1): e0115136, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25629400

RESUMO

Deserts are particularly vulnerable to human impacts and have already suffered a substantial loss of biodiversity. In harsh and variable desert environments, large herbivores typically occur at low densities, and their large carnivore predators occur at even lower densities. The continued survival of large carnivores is key to healthy functioning desert ecosystems, and the ability to gather reliable information on these rare low density species, including presence, abundance and density, is critical to their monitoring and management. Here we test camera trap methodologies as a monitoring tool for an extremely rare wide-ranging large felid, the critically endangered Saharan cheetah (Acinonyx jubatus hecki). Two camera trapping surveys were carried out over 2-3 months across a 2,551 km2 grid in the Ti-n-haggen region in the Ahaggar Cultural Park, south central Algeria. A total of 32 records of Saharan cheetah were obtained. We show the behaviour and ecology of the Saharan cheetah is severely constrained by the harsh desert environment, leading them to be more nocturnal, be more wide-ranging, and occur at lower densities relative to cheetah in savannah environments. Density estimates ranged from 0.21-0.55/1,000 km2, some of the lowest large carnivore densities ever recorded in Africa, and average home range size over 2-3 months was estimated at 1,583 km2. We use our results to predict that, in order to detect presence of cheetah with p>0.95 a survey effort of at least 1,000 camera trap days is required. Our study identifies the Ahaggar Cultural Park as a key area for the conservation of the Saharan cheetah. The Saharan cheetah meets the requirements for a charismatic flagship species that can be used to "market" the Saharan landscape at a sufficiently large scale to help reverse the historical neglect of threatened Saharan ecosystems.


Assuntos
Acinonyx , Clima Desértico , Ecossistema , Argélia , Animais , Biodiversidade , Geografia , Humanos , Densidade Demográfica , Comportamento Predatório
12.
Science ; 346(6205): 79-81, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25278609

RESUMO

Population viability is driven by individual survival, which in turn depends on individuals balancing energy budgets. As carnivores may function close to maximum sustained power outputs, decreased food availability or increased activity may render some populations energetically vulnerable. Prey theft may compromise energetic budgets of mesopredators, such as cheetahs and wild dogs, which are susceptible to competition from larger carnivores. We show that daily energy expenditure (DEE) of cheetahs was similar to size-based predictions and positively related to distance traveled. Theft at 25% only requires cheetahs to hunt for an extra 1.1 hour per day, increasing DEE by just 12%. Therefore, not all mesopredators are energetically constrained by direct competition. Other factors that increase DEE, such as those that increase travel, may be more important for population viability.


Assuntos
Acinonyx/metabolismo , Acinonyx/psicologia , Carnivoridade , Cadeia Alimentar , Comportamento Predatório , Animais , Comportamento Competitivo , Metabolismo Energético
14.
Front Zool ; 10(1): 62, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24152378

RESUMO

BACKGROUND: Multi-level fission-fusion societies, characteristic of a number of large brained mammal species including some primates, cetaceans and elephants, are among the most complex and cognitively demanding animal social systems. Many free-ranging populations of these highly social mammals already face severe human disturbance, which is set to accelerate with projected anthropogenic environmental change. Despite this, our understanding of how such disruption affects core aspects of social functioning is still very limited. RESULTS: We now use novel playback experiments to assess decision-making abilities integral to operating successfully within complex societies, and provide the first systematic evidence that fundamental social skills may be significantly impaired by anthropogenic disruption. African elephants (Loxodonta africana) that had experienced separation from family members and translocation during culling operations decades previously performed poorly on systematic tests of their social knowledge, failing to distinguish between callers on the basis of social familiarity. Moreover, elephants from the disrupted population showed no evidence of discriminating between callers when age-related cues simulated individuals on an increasing scale of social dominance, in sharp contrast to the undisturbed population where this core social ability was well developed. CONCLUSIONS: Key decision-making abilities that are fundamental to living in complex societies could be significantly altered in the long-term through exposure to severely disruptive events (e.g. culling and translocation). There is an assumption that wildlife responds to increasing pressure from human societies only in terms of demography, however our study demonstrates that the effects may be considerably more pervasive. These findings highlight the potential long-term negative consequences of acute social disruption in cognitively advanced species that live in close-knit kin-based societies, and alter our perspective on the health and functioning of populations that have been subjected to anthropogenic disturbance.

15.
Biol Lett ; 9(5): 20130620, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24004493

RESUMO

Predator-prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s(-1) and accelerated up to 7.5 m s(-2) with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5-8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival.


Assuntos
Acinonyx/fisiologia , Comportamento Predatório , Animais
16.
Ecology ; 94(5): 1123-30, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23858652

RESUMO

Understanding how entire ecosystems maintain stability in the face of climatic and human disturbance is one of the most fundamental challenges in ecology. Theory suggests that a crucial factor determining the degree of ecosystem stability is simply the degree of synchrony with which different species in ecological food webs respond to environmental stochasticity. Ecosystems in which all food-web pathways are affected similarly by external disturbance should amplify variability in top carnivore abundance over time due to population interactions, whereas ecosystems in which a large fraction of pathways are nonresponsive or even inversely responsive to external disturbance will have more constant levels of abundance at upper trophic levels. To test the mechanism underlying this hypothesis, we used over half a century of demographic data for multiple species in the Serengeti (Tanzania) ecosystem to measure the degree of synchrony to variation imposed by an external environmental driver, the El Niño Southern Oscillation (ENSO). ENSO effects were mediated largely via changes in dry-season vs. wet-season rainfall and consequent changes in vegetation availability, propagating via bottom-up effects to higher levels of the Serengeti food web to influence herbivores, predators and parasites. Some species in the Serengeti food web responded to the influence of ENSO in opposite ways, whereas other species were insensitive to variation in ENSO. Although far from conclusive, our results suggest that a diffuse mixture of herbivore responses could help buffer top carnivores, such as Serengeti lions, from variability in climate. Future global climate changes that favor some pathways over others, however, could alter the effectiveness of such processes in the future.


Assuntos
El Niño Oscilação Sul , Cadeia Alimentar , Comportamento Predatório , África , Animais , Antílopes , Aves , Mamíferos , Plantas , Dinâmica Populacional , Chuva , Estações do Ano , Fatores de Tempo
17.
PLoS One ; 6(12): e28671, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163323

RESUMO

Infectious diseases are increasingly recognised to be a major threat to biodiversity. Disease management tools such as control of animal movements and vaccination can be used to mitigate the impact and spread of diseases in targeted species. They can reduce the risk of epidemics and in turn the risks of population decline and extinction. However, all species are embedded in communities and interactions between species can be complex, hence increasing the chance of survival of one species can have repercussions on the whole community structure. In this study, we use an example from the Serengeti ecosystem in Tanzania to explore how a vaccination campaign against Canine Distemper Virus (CDV) targeted at conserving the African lion (Panthera leo), could affect the viability of a coexisting threatened species, the cheetah (Acinonyx jubatus). Assuming that CDV plays a role in lion regulation, our results suggest that a vaccination programme, if successful, risks destabilising the simple two-species system considered, as simulations show that vaccination interventions could almost double the probability of extinction of an isolated cheetah population over the next 60 years. This work uses a simple example to illustrate how predictive modelling can be a useful tool in examining the consequence of vaccination interventions on non-target species. It also highlights the importance of carefully considering linkages between human-intervention, species viability and community structure when planning species-based conservation actions.


Assuntos
Cinomose/prevenção & controle , Cinomose/virologia , Ecossistema , Acinonyx , Animais , Simulação por Computador , Conservação dos Recursos Naturais , Vírus da Cinomose Canina/metabolismo , Feminino , Quênia , Leões , Masculino , Tanzânia , Vacinação , Viroses/terapia
18.
Oecologia ; 167(2): 305-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21761171

RESUMO

Both predation and individual variation in life history traits influence population dynamics. Recent results from laboratory predator-prey systems suggest that differences between individuals can also influence predator-prey dynamics when different genotypes experience different predation-associated mortalities. Despite the growing number of studies in this field, there is no synthesis identifying the overall importance of the interactions between predation and individual heterogeneity and their role in shaping the dynamics of free-ranging populations of vertebrates. We aim to fill this gap with a review that examines how individual variability in prey susceptibility, in predation costs, in predator selectivity, and in predatory performance, might influence prey population dynamics. Based on this review, it is clear that (1) predation risk and costs experienced by free-ranging prey are associated with their phenotypic attributes, (2) many generalist predator populations consist of individual specialists with part of the specialization associated with their phenotypes, and (3) a complete understanding of the population dynamic consequences of predation may require information on individual variability in prey selection and prey vulnerability. Altogether, this work (1) highlights the importance of maintaining long-term, detailed studies of individuals of both predators and prey in contrasting ecological conditions, and (2) advocates for a better use of available information to account for interactive effects between predators and their prey when modelling prey population dynamics.


Assuntos
Cadeia Alimentar , Modelos Biológicos , Vertebrados/fisiologia , Animais , Ecossistema , Dinâmica Populacional , Comportamento Predatório
19.
Proc Biol Sci ; 278(1722): 3270-6, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-21411454

RESUMO

The value of age is well recognized in human societies, where older individuals often emerge as leaders in tasks requiring specialized knowledge, but what part do such individuals play in other social species? Despite growing interest in how effective leadership might be achieved in animal social systems, the specific role that older leaders may play in decision-making has rarely been experimentally investigated. Here, we use a novel playback paradigm to demonstrate that in African elephants (Loxodonta africana), age affects the ability of matriarchs to make ecologically relevant decisions in a domain critical to survival-the assessment of predatory threat. While groups consistently adjust their defensive behaviour to the greater threat of three roaring lions versus one, families with younger matriarchs typically under-react to roars from male lions despite the severe danger they represent. Sensitivity to this key threat increases with matriarch age and is greatest for the oldest matriarchs, who are likely to have accumulated the most experience. Our study provides the first empirical evidence that individuals within a social group may derive significant benefits from the influence of an older leader because of their enhanced ability to make crucial decisions about predatory threat, generating important insights into selection for longevity in cognitively advanced social mammals.


Assuntos
Comportamento Animal/fisiologia , Elefantes/fisiologia , Processos Grupais , Liderança , Comportamento Social , Estimulação Acústica , Fatores Etários , Animais , Feminino , Quênia , Modelos Lineares , Longevidade , Observação , Gravação em Vídeo
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