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2.
Front Vet Sci ; 10: 1229676, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026639

RESUMO

The need to reconcile food production, the safeguarding of nature, and the protection of public health is imperative in a world of continuing global change, particularly in the context of risks of emerging zoonotic disease (EZD). In this paper, we explored potential land use strategies to reduce EZD risks using a landscape approach. We focused on strategies for cases where the dynamics of pathogen transmission among species were poorly known and the ideas of "land-use induced spillover" and "landscape immunity" could be used very broadly. We first modeled three different land-use change scenarios in a region of transition between the Cerrado and the Atlantic Forest biodiversity hotspots. The land-use strategies used to build our scenarios reflected different proportions of native vegetation cover, as a proxy of habitat availability. We then evaluated the effects of the proportion of native vegetation cover on the occupancy probability of a group of mammal species and analyzed how the different land-use scenarios might affect the distribution of species in the landscape and thus the risk of EZD. We demonstrate that these approaches can help identify potential future EZD risks, and can thus be used as decision-making tools by stakeholders, with direct implications for improving both environmental and socio-economic outcomes.

3.
Conserv Biol ; 36(2): e13860, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34766386

RESUMO

When in 2010 the world's governments pledged to increase protected area coverage to 17% of the world's land surface, several Central African countries had already set aside 25% of their northern savannas for conservation. To evaluate the effectiveness of this commitment, we analyzed the results of 68 multispecies surveys conducted in the seven main savanna national parks in Central Africa (1960-2017). We also assembled information on potential drivers of large herbivore population trends (rainfall and number of rangers) and on tourist numbers and revenues. In six out of the seven parks, wild large herbivore populations declined dramatically over time, livestock numbers increased severalfold, and tourism, the pillar under a once thriving local wildlife industry, collapsed. Zakouma National Park (Chad) stood out because its large herbivore populations increased, an increase that was positively correlated with rainfall and number of rangers (a proxy for management inputs). With increasing insecurity and declining revenues, governments find themselves confronted with too few resources to protect vast areas. To deal with this conversation overstretch, we propose to extend the repeatedly promoted solutions--scaled up funding, enhanced management--with a strategic retreat, focusing scarce resources on smaller areas to save wildlife in the Central African savannas.


Sobredimensionamiento de la Conservación y la Declinación a Largo Plazo de la Fauna y el Turismo en las Sabanas de África Central Resumen Cuando los gobiernos del mundo se comprometieron en 2010 a incrementar la cobertura de áreas protegidas al 17% de la superficie terrestre del planeta, varios países del centro de África ya habían dispuesto el 25% de sus sabanas ubicadas al norte de la región para la conservación. Para evaluar la efectividad de este compromiso, analizamos los resultados de 68 censos multiespecies realizados en los siete parques nacionales principales de la sabana en África Central (1960-2017). También ensamblamos información sobre los causantes principales de las tendencias poblacionales de los grandes herbívoros (lluvias, número de guardaparques) y sobre las cifras e ingresos del turismo. En seis de los siete parques, las poblaciones de los grandes herbívoros silvestres declinaron dramáticamente con el tiempo, el número de cabezas de ganado incrementó varias veces y el turismo, el pilar de una industria faunística próspera en su momento, colapsó. El Parque Nacional Zakouma en Chad resaltó debido a que las poblaciones de herbívoros grandes incrementaron en esta localidad, un incremento que estuvo relacionado positivamente con las lluvias y el número de guardabosques (un sustituto para las aportaciones de manejo). Con el incremento en la inseguridad y la declinación de los ingresos, los gobiernos se encuentran de frente con muy pocos recursos para proteger áreas extensas. Para afrontar este sobredimensionamiento de la conservación, proponemos ampliar las soluciones que se promueven repetidamente - incrementos al financiamiento, manejo mejorado - con un repliegue estratégico, el cual enfoque los recursos escasos en las áreas más pequeñas para rescatar a la fauna de las sabanas del centro de África.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Animais , Conservação dos Recursos Naturais/métodos , Ecossistema , Pradaria , Turismo
4.
PLoS One ; 16(4): e0249904, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33831091

RESUMO

Two aquatic invasive alien rodents, the coypu (Myocastor coypus) and muskrat (Ondatra zibethicus), have taken over a significant amount of wetlands in France. Pays de la Loire is an administrative region of about 32 000 km2 in the Western France with 6.3% of its area in wetlands (excluding the Loire River). Populations of coypus and muskrats are established and a permanent control programme has been set to reduce their impacts. The control plan is based on few professional trappers and many volunteers which makes this programme unique compared to other programme relying on professionals only. The aim of this study is to analyse the temporal and spatial dynamics of coypu and muskrat captures during the last 10 years to evaluate their effectiveness. The number of rodents removed per year increased by 50% in 10 years and reached about 288 000 individuals in 2016 with about 80% of them being coypus. During the same time length, the number of trappers involved in the programme also increased by 50% to reach 3 000 people in 2016. Although the raise of coypus and muskrats trapped can possibly be explained by an increase of the number of trappers, the number of coypus removed per trapper per year increased by 22%. Despite the outstanding number of individuals removed per year, our results suggest that the programme does not limit the population dynamics of coypus. Finally, since 2017, the number of data gathered from municipalities decreased, as did the total number of individuals trapped. Indeed, although rewards are crucial to recruit new volunteers, subsidies from local and regional authorities are declining. Decision makers and financers should be encouraged to fund this programme from the perspectives of the direct or indirect costs related to the presence of aquatic invasive alien rodents in wetlands.


Assuntos
Arvicolinae/fisiologia , Espécies Introduzidas/tendências , Animais , Biomassa , França , Análise Espaço-Temporal , Áreas Alagadas
5.
Glob Chang Biol ; 26(3): 1138-1154, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31597213

RESUMO

Land-use changes and the expansion of protected areas (PAs) have amplified the interaction between protected and unprotected areas worldwide. In this context, 'interface processes' (human-nature and cross-boundary interactions inside and around PAs) have become central to issues around the conservation of biodiversity and ecosystem services. This scientific literature review aimed to explore current knowledge and research gaps on interface processes regarding terrestrial PAs. At first, 3,515 references related to the topic were extracted through a standardized search on the Web of Science and analyzed with scientometric techniques. Next, a full-text analysis was conducted on a sample of 240 research papers. A keyword analysis revealed a wide diversity of research topics, from 'pure' ecology to sociopolitical research. We found a bias in the geographical distribution of research, with half the papers focusing on eight countries. Additionally, we found that the spatial extent of cross-boundary interactions was rarely assessed, preventing any clear delimitation of PA interactive zones. In the 240 research papers we scanned, we identified 403 processes that were studied. The ecological effects of PAs were well documented and appeared to be positive overall. In contrast, the effects of PAs on local communities were understudied and, according to the literature focusing on these, were very variable according to local contexts. Our findings highlight key research advances on interface processes, especially regarding the ecological outcomes of PAs, the influence of human activities on biodiversity, and PA governance issues. In contrast, main knowledge gaps concern the spatial extent of interactive zones, as well as the interactions between local people and conservation actions and how to promote synergies between them. While the review was limited to terrestrial PAs, its findings allow us to propose research priorities for tackling environmental and socioeconomic challenges in the face of a rapidly changing world.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Ecologia , Humanos
7.
Oecologia ; 156(3): 715-26, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18357470

RESUMO

We studied the nutritional behaviour of hinds foraging on a mixed-forest edge by direct observation of their choices at each season and by measuring nutrient concentration in the plants. We compared nutrient concentrations in the observed diets with those in the total available vegetation, and with those of 1,000 randomly simulated diets in which we included only those plants that were actually eaten by the animal. Whether the available or the consumed feeds were used as the basis for comparisons had important consequences due to the presence of conifers and ferns, which were high in soluble sugars but were never eaten by the animals (potentially due to their toxicity). The selected diets were lower in sugars than the total available vegetation in summer, but were actually higher in sugars than the random diets generated from consumed forage species only. Hind diets contained more soluble sugars but not more protein than simulated diets in all seasons. Contrary to our prediction, anti-nutritional compounds (ADL and tannins) were avoided only in winter. Compared to simulated diets, hinds consumed more tannins in spring and summer and more ADL in summer and autumn. We suggest that this was a consequence of selection for soluble sugars, because the preferred plant species, which had high soluble sugar concentrations, also contained a large proportion of the anti-nutritional compounds eaten. In winter, the grass-dominated diets contained more fibre (NDF) and less ADL than the simulated diets, indicating that hinds orient their feeding towards digestible fibres. The switch from a browser to a grazer diet was related to a change in the availability of the nutrients, mainly soluble sugars. In our study, grasses contained more soluble sugars and proteins than deciduous browse during winter. This calls into question the dichotomy usually assumed in the literature between grass and browse in terms of nutrient content.


Assuntos
Cervos/fisiologia , Dieta/veterinária , Comportamento Alimentar/fisiologia , Alimentos , Árvores , Animais , Feminino , Plantas/química
8.
Proc Biol Sci ; 274(1615): 1287-91, 2007 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-17341457

RESUMO

It is generally assumed that an individual of a prey species can benefit from an increase in the number of its group's members by reducing its own investment in vigilance. But what behaviour should group members adopt in relation to both the risk of being preyed upon and the individual investment in vigilance? Most models assume that individuals scan independently of one another. It is generally argued that it is more profitable for each group member owing to the cost that coordination of individual scans in non-overlapping bouts of vigilance would require. We studied the relationships between both individual and collective vigilance and group size in Defassa waterbuck, Kobus ellipsiprymnus defassa, in a population living under a predation risk. Our results confirmed that the proportion of time an individual spent in vigilance decreased with group size. However, the time during which at least one individual in the group scanned the environment (collective vigilance) increased. Analyses showed that individuals neither coordinated their scanning in an asynchronous way nor scanned independently of one another. On the contrary, scanning and non-scanning bouts were synchronized between group members, producing waves of collective vigilance. We claim that these waves are triggered by allelomimetic effects i.e. they are a phenomenon produced by an individual copying its neighbour's behaviour.


Assuntos
Comportamento Animal , Ruminantes/psicologia , Animais , República Centro-Africana , Modelos Lineares , Comportamento Predatório , Estatísticas não Paramétricas , Gravação de Videoteipe
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