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With increasing loss and fragmentation of habitats driving the emerging global extinction crisis, paired with limited resources for conservation, there is an immense need to identify and prioritize the most important areas for conservation actions. The goal of this study was to measure, map and rank core areas and corridors for mainland clouded leopard (a forest indicator species) across its entire range in Southeast Asia. We used an empirically based landscape resistance model developed from range‐wide camera survey data, cumulative resistant kernel analysis to define core areas and least‐cost network analysis to identify corridors for long‐distance dispersal. We then ranked core areas based on their strength and size, and corridors based on their strength and the strength of core areas they connect. We found that the most important core areas and corridors are concentrated in Southeast Asia, largely in Myanmar, Laos and Malaysia. Myanmar contains nearly the entirety of the first and third highest ranked core areas, as well as the most important network of corridors in SE Asia. Almost the entire territory of Laos constitutes one large potential core area, ranked as the second most important across the clouded leopard's range. A large number (22) of very small (<8000 km2) and fairly isolated core areas are in China. Only 24% of clouded leopard core areas and 17% of corridors are protected. This is the first example of using empirical models to prioritize conservation actions across the full range of a large carnivore. Our analysis identifies the location, size and connectivity of the most important remaining habitats of the clouded leopard across its range, which could provide quantitative guidance in the efforts to maximize the efficacy of regional conservation initiatives to conserve this species and the ecosystems it inhabits. [ABSTRACT FROM AUTHOR]

Abstract: Rest sites are key locations to many animals but their selection has been poorly studied in large carnivores. We investigated seasonal diurnal rest site selection by spotted hyaenas (Crocuta crocuta) in Hwange National Park, Zimbabwe. We assessed the effects on hyaena diurnal rest site selection of (1) distance to the nearest waterhole, as waterholes can be considered prey hotspots in the study ecosystem, (2) habitat type and vegetation characteristics, in particular visibility as it influences detection risk and shade for thermoregulation, (3) location within the core territory of their main competitor/predator, the African lion (Panthera leo), where encounter risk would be higher, (4) distance to the closest lion and (5) distance to the nearest road as they can facilitate travelling by carnivores. We defined rest sites as midday locations of hyaenas equipped with GPS collars. Hyaenas preferred to rest in woodland areas with low visibility, close to roads and far from a lion. Distance to the nearest waterhole and location within lion core territory did not affect hyaena rest site selection. Overall, our study points to the combined importance of the structure of the vegetation (providing safety and shade), the availability of roads (to move through and exploit this bushed environment) and the avoidance of proximity to lions. [ABSTRACT FROM AUTHOR]

We investigated the paradox of why Amazonian manatees Trichechus inunguis undergo seasonal migrations to a habitat where they apparently fast. Ten males were tracked using VHF telemetry between 1994 and 2006 in the Mamirauá and Amanã Sustainable Development Reserves, constituting the only long-term dataset on Amazonian manatee movements in the wild. Their habitat was characterized by analysing aquatic space and macrophyte coverage dynamics associated with the annual flood-pulse cycle of the River Solimões. Habitat information came from fieldwork, two hydrographs, a three-dimensional model of the water bodies and classifications of Landsat-TM/ETM+ images. We show that during high-water season (mid-May to end-June), males stay in várzea lakes in association with macrophytes, which they select. We then show that, during low-water (October–November), the drastic reduction in aquatic space in the várzea leads to the risk of their habitat drying out and increases the manatees' vulnerability to predators such as caimans, jaguars and humans. This explains why males migrate to Ria Amanã. Based on data on illegal hunting, we argue that this habitat variability influences females to migrate too. We then use published knowledge of the environment's dynamics to argue that when water levels are high, the habitats that can support the largest manatee populations are the várzeas of white-water rivers, and we conjecture that rias are the species' main low-water refuges throughout Western Amazonia. Finally, we warn that the species may be at greater risk than previously thought, because migration and low-water levels make manatees particularly vulnerable to hunters. Moreover, because the flooding regime of Amazonian rivers is strongly related to large-scale climatic phenomena, there might be a perilous connection between climate change and the future prospects for the species. Our experience reveals that the success of research and conservation of wild Amazonian manatees depends on close working relationships with local inhabitants. [ABSTRACT FROM AUTHOR]

American mink Mustela vison, originally bred in fur farms, have become established in areas occupied by native endangered Southern river otter Lontra provocax, in Patagonia. In accordance with European experience, this biological invasion in South America raises questions about the interaction between invasive mink and native otter, from the viewpoints of both community assembly and conservation. We set out (1) to find which aspects of habitat structure were related to the distribution of signs of both this invasive species and Southern river otter Lontra provocax, in Argentinean Patagonia and their most common prey and (2) to test general predictions of niche partitioning between these two species. Based on surveys of 447 of 600 m transects for otter and mink scats/footprints along the waterside of lakes and rivers in the Andean Patagonian region, we compared diet composition (from scat analysis) and micro-habitat preferences (from field signs) of the two species. Otters were more specialist than mink in habitat use and diet. Mink used different habitats in other river basins where otters were absent. Where they occurred together in the basin of the Limay River, the distributions of their signs were similar, and mink diet was more similar to that of otters. There was no detectable difference in otter diet before and after mink arrival in the Limay basin. Contrary to the prediction of niche partitioning, and to the findings of European studies, resource use by mink was more similar to that of otters where the species occurred sympatrically than where they were allopatric. [ABSTRACT FROM AUTHOR]

Predators may influence their prey populations not only through direct lethal effects, but also through redirect behavioral changes. Here, we combined spatiotemporal fine-scale data from GPS radio collars on lions with habitat use information on 11 African herbivores in Hwange National Park (Zimbabwe) to test whether the risk of predation by lions influenced the distribution of herbivores in the landscape. Effects of long-term risk of predation (likelihood of lion presence calculated over four months) and short-term risk of predation (actual presence of lions in the vicinity in the preceding 24 hours) were contrasted. The long-term risk of predation by lions appeared to influence the distributions of all browsers across the landscape, but not of grazers. This result strongly suggests that browsers and grazers, which face different ecological constraints, are influenced at different spatial and temporal scales in the variation of the risk of predation by lions. The results also show that all herbivores tend to use more open habitats preferentially when lions are in their vicinity, probably an effective anti-predator behavior against such an ambush predator. Behaviorally induced effects of lions may therefore contribute significantly to structuring African herbivore communities, and hence possibly their effects on savanna ecosystems. [ABSTRACT FROM AUTHOR]

1. The impacts of agricultural intensification on farmland wildlife have been the subject of increasing concern, particularly over the last two decades. Population declines have occurred for a number of mammalian species, sometimes drastically so, and changes in farming practice are believed to be significant contributory factors. 2. The major policy instruments for delivering environmental benefits on farmland are agri-environment schemes. These encourage farmers to adopt more environmentally sensitive farming practices to promote farmland biodiversity. Additionally, compulsory set-aside, which reduces agricultural surplus, could also have positive impacts on wildlife. In this paper we consider some of the putative benefits of agri-environment schemes and set-aside for mammals. 3. We review how establishment and management options within agri-environment schemes and set-aside might affect habitat resources for mammals. For example, conservation headlands increase plant and invertebrate resources within the crop edge for mammals such as wood mice. Grassy field margins can support communities of smaller mammals, and hedgerows may act as important commuting and hunting routes. Their potential will depend on factors such as seed mixtures used, timing and severity of cutting, and length of time they have been in place. 4. At a farm level, habitat heterogeneity may be increased through organic agriculture, which is supported by some agri-environment schemes. Studies suggest significant benefits to mammals, including wood mice and bats. However, it is increasingly recognized that effective conservation of farmland mammals must seek solutions at the landscape scale, addressing such issues as habitat connectivity between farms. One approach may be the better targeting of scheme agreements. 5. We suggest that agri-environment schemes and set-aside can contribute to the conservation of mammals on farmland. Recent policy changes are likely to have further positive impacts on farmland wildlife but appropriate mammal monitoring programmes must be developed rigorously to assess their effects. [ABSTRACT FROM AUTHOR]

Habitat loss and reduction in quality, together with increasing homogeneity of the farmed landscape and more intensive field management, are believed to be major drivers of biodiversity loss on farmland. Organic farms demonstrate features that are now rare elsewhere in UK farming systems, such as crop rotations incorporating grass leys, exclusion of synthetic pesticides and fertilizers, and reliance on animal and green manures. They may also contain greater densities of uncropped habitats such as hedgerows. In this study, we examined whether organic farming affected populations of one group of insects of conservation interest, butterflies, on farmland. The abundance of butterflies on pairs of organically and conventionally managed farms was recorded over 3 years and a number of habitat and crop variables, likely to be related to butterfly abundance, were also measured. Organic farms attracted significantly more butterflies overall than conventional farms. Significantly more butterflies in both farming systems were recorded over the uncropped field margin than the crop edge. The difference in butterfly abundance between crop edge and field margin was relatively greater in conventional than organic systems. Species richness of butterflies tended to be greater on organic farms. Five species of butterfly were significantly more abundant on organic farms in at least 1 year, while no species was significantly more abundant on conventional farms. Organic and conventional cropping patterns differed, the former having proportionally more grass leys, and hedgerows were larger on organic farms. Although no significant effects of farming system on the numbers of grass or forb species present in the field margin or crop edge were detected, some individual plant species showed differences in frequency between organic and conventional field boundaries. Increasing the extent of organic farming, or practices associated with it, could help to restore biodiversity in agricultural landscapes. [ABSTRACT FROM AUTHOR]

Fifteen years of monitoring in the Bale Mountains provide a valuable time series to better understand the dynamics of populations of the endangered Ethiopian wolf Canis simensis in the face of epizootics and increasing human pressure. Line-transect counts in four study areas were used to identify trends in the local abundances of wolves, people, livestock and domestic dogs (a putative rabies reservoir). Estimates of wolf abundance were validated against total counts in prime wolf habitats, where two local populations decimated by rabies in the early 1990s had recovered fully by 2000. Growth appeared to be regulated by negative density dependence, but the rate of growth was unexpectedly low at reduced densities. Limitations to rapid growth, including an initial gap for which data were sparse, are discussed. In a poorer habitat, wolf abundance estimates were less reliable but indicated slight fluctuations without an overall trend. A local extinction was recorded in an area of marginal habitat. With this exception, trends in wolf abundances were unrelated to trends in the abundance of people, livestock or dogs. Rabies emerged as the main cause of decline for high-density populations. The rapidly increasing livestock grazing pressure in Bale gives cause for concern, calling for further research on its impacts upon long-term wolf survival. [ABSTRACT FROM AUTHOR]

Summary 1. Farmland is readily divisible into linear habitats such as hedges, and non-linear habitats such as fields and woodlots. In agricultural landscapes, conservationists have generally focused on enhancing linear habitats, but there are few data from which to judge whether or not this is a good strategy for biodiversity. 2. We investigated whether the linear or non-linear character of habitat patches, mediated by edge effects, has an impact on the abundance, diversity and richness of the small mammal communities that live within and between them. 3. In particular, we hypothesized, first, that edge effects cause narrow linear habitats to be avoided by specialists such as the bank vole Clethrionomys glareolus , but not by generalists such as the wood mouse Apodemus sylvaticus ; secondly, that edge effects lead to specialists being present in atypical habitat, through excursions at the interface between two habitats. 4. We tested these hypotheses by live-trapping small mammals in grids in the centres of three non-linear farmland habitats (woodlots, set-aside and crop fields) and in field boundaries consisting of a series of adjoining linear habitats. We compared mammal communities in the non-linear habitats with the field boundary as a whole, and with the individual linear habitat elements within the boundary. 5. There was no evidence that specialists avoided linear habitats. Indeed, the field boundary was the most species-rich habitat surveyed, and bank voles were more abundant in linear hedgerow than in non-linear woodland. Bank voles were present in linear set-aside and in the crop edge, but never in non-linear blocks of set-aside or crop, implying that they diffused out of the hedgerow into the adjacent habitats. There was no evidence of an effect of habitat linearity on field voles Microtus agrestis , wood mice or common shrews Sorex araneus . 6. Our results suggest that on uncropped land such as set-aside, the linear or non-linear character of habitats... [ABSTRACT FROM AUTHOR]