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Camera traps are a key tool in ecological studies, and are increasingly being used to understand entire communities. However, robust inferences continue to be hampered by low detection of rare and elusive species. Attractants can be used to increase detection rates, but may also alter behaviour, and little research has evaluated short-term, localized response to the presence of attractants. We conducted three camera trap surveys in Kibale National Park, Uganda, using food baits and scent lures ("attractants") at each camera station to entice small carnivores to pass in front of camera stations. To examine the interrelationship between scavenging and response to attractants, we also placed camera traps at five food refuse pits. We modelled the effect of attractant and duration of trap placement on the detection probability of small carnivores and selected African golden cat Caracal aurata prey items. We examine transient site response of each species, by comparing our observed likelihood of detection in each 24 h period from 1-7 d following refreshing of attractants to randomly generated capture histories. African civet Civettictis civetta, rusty-spotted genet Genetta maculata, African palm civet Nandinia binotata, and marsh mongoose Atilax paludinosus detection probabilities were highest and Weyns's red duiker Cephalophus wenysi detection probability was lowest immediately after attractants were placed. Within 24 h after attractant was placed, rusty-spotted genet and African palm civet were more likely to be detected and African golden cat, red duiker, and blue duiker Philantomba monticola were less likely to be detected. Our results suggest that attractants can increase detection of small-bodied species and include some arboreal species in terrestrial camera trap sampling. However, attractants may also alter short-term visitation rates of some species, with potentially cascading effects on others. Community level and intraguild interaction studies should control for the potentially confounding effects of attractants on spatial activity patterns.

Many ungulates migrate between distinct summer and winter ranges, and identifying, mapping, and conserving these migration corridors have become a focus of local, regional, and global conservation efforts. Brownian bridge movement models (BBMMs) are commonly used to empirically identify these seasonal migration corridors; however, they require location data sampled at relatively frequent intervals to obtain a robust estimate of an animal's movement path. Fitting BBMMs to sparse location data violates the assumption of conditional random movement between successive locations, overestimating the area (and width) of a migration corridor when creating individual and population‐level occurrence distributions and precluding the use of low‐frequency, or sparse, data in mapping migration corridors. In an effort to expand the utility of BBMMs to include sparse GPS data, we propose an alternative approach to model migration corridors from sparse GPS data. We demonstrate this method using GPS data collected every 2 h from four mule deer (Odocoileus hemionus) and four elk (Cervus canadensis) herds within Wyoming and Idaho. First, we used BBMMs to estimate a baseline corridor for the 2‐h data. We then subsampled the 2‐h data to one location every 12 h (a proxy for sparse data) and fitted BBMMs to the 12‐h data using a fixed motion variance (FMV) value, instead of estimating the Brownian motion variance empirically. A range of FMV values was tested to identify the value that best approximated the baseline migration corridor. FMV values within a species‐specific range (mule deer: 400–1200 m2; elk: 600–1600 m2) successfully delineated migration corridors similar to the 2‐h baseline corridors; overall, lower values delineated narrower corridors and higher values delineated wider corridors. Optimal FMV values of 800 m2 (mule deer) and 1000 m2 (elk) decreased the inflation of the 12‐h corridors relative to the 2‐h corridors from traditional BBMMs. This FMV approach thus enables using sparse movement data to approximate realistic migration corridor dimensions, providing an important alternative when movement data are collected infrequently. This approach greatly expands the number of datasets that can be used for migration corridor mapping—a useful tool for management and conservation across the globe. [ABSTRACT FROM AUTHOR]

The size of the home range of a mammal is affected by numerous factors. However, in the normally solitary, but polygynous, Leopard (Panthera pardus), home range size and maintenance is complicated by their transitory social grouping behavior, which is dependent on life history stage and/or reproductive status. In addition, the necessity to avoid competition with conspecifics and other large predators (including humans) also impacts upon home range size. We used movement data from 31 sites across Africa, comprising 147 individuals (67 males and 80 females) to estimate the home range sizes of leopards. We found that leopards with larger home ranges, and in areas with more vegetation, spent longer being active and generally traveled faster, and in straighter lines, than leopards with smaller home ranges. We suggest that a combination of bottom-up (i.e. preferred prey availability), top-down (i.e. competition with conspecifics), and reproductive (i.e. access to mates) factors likely drive the variability in Leopard home range sizes across Africa. However, the maintenance of a large home range is energetically expensive for leopards, likely resulting in a complex evolutionary trade-off between the satisfaction of basic requirements and preventing potentially dangerous encounters with conspecifics, other predators, and people. [ABSTRACT FROM AUTHOR]

Research on drivers of demographic rates has mostly focused on top predators and their prey, and comparatively less research has considered the drivers of mesopredator demography. Of those limited studies, most focused on top‐down effects of apex predators on mesopredator population dynamics, whereas studies investigating alternative mechanisms are less common.In this study, we tested hypotheses related to top‐down, bottom‐up and density‐dependent regulation of demographic rates in an imperilled mesopredator, the cheetah (Acinonyx jubatus).We used a 25‐year dataset of lion density, cheetah density and prey density from the Mun‐Ya‐Wana Conservancy in South Africa and assessed the effects of top‐down, bottom‐up and density‐dependent drivers on cheetah survival and reproduction.In contrast to the top‐down and bottom‐up predictions, both adult and juvenile cheetahs experienced the lowest survival during months with high prey densities and low lion densities. We observed support only for a density‐dependent response in juvenile cheetahs, where they had a higher probability of reaching independence during times with low cheetah density and low prey density. We did not identify any strong drivers of litter size.Collectively, our results indicate that high apex predator abundance might not always have negative effects on mesopredator populations, and suggest that context dependency in top‐down, bottom‐up and density‐dependent factors may regulate demographic rates of cheetahs and other mesopredators. Our results highlight the complexities of population‐level drivers of cheetah demographic rates and the importance of considering multiple hypotheses of mesopredator population regulation. [ABSTRACT FROM AUTHOR]

The article offers information about a study which aims to nvestigate seasonal variations of space use patterns in nyala as well as to test the effects of sex and rainfall as a metric of seasonal variability on home range size. Information on the materials and methods used in home range size variation research in nyala is presented.

The devolution of user rights of wildlife in southern Africa has led to a widespread land-use shift from livestock farming to game ranching. The economic advantages of game ranching over livestock farming are significant, but so too are the risks associated with breeding financially valuable game where free-ranging wildlife pose a credible threat. Here, we assessed whether the conservation potential of game ranching, and a decentralized approach to conservation more generally, may be undermined by an increase in human-wildlife conflict. We demonstrate that game rancher tolerance towards free-ranging wildlife has significantly decreased as the game ranching industry has evolved. Our findings reveal a conflict of interest between wealth and wildlife conservation resulting from local decision making in the absence of adequate centralized governance and evidence-based best practice. As a fundamental pillar of devolution-based natural resource management, game ranching proves an important mechanism for economic growth, albeit at a significant cost to conservation. [ABSTRACT FROM AUTHOR]

Heavy metals are persistent environmental contaminants, and wild animals are increasingly exposed to the harmful effects of compounds of anthropogenic origin, even in areas distant from industrial centers. We used atomic absorption spectrometry to determine levels of cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn) in liver and kidney of wild Eurasian beavers ( Castor fiber) in Poland. Cd concentrations in liver (0.21 ± 0.44 μg/g) and in kidney (2.81 ± 4.52 μg/g) were lower in juvenile than in adult beavers. Pb concentrations in liver (0.08 ± 0.03 μg/g) and kidney (0.08 ± 0.03 μg/g) were similar among all individuals, while both Cu and Zn levels were higher in liver (Cu 9.2 ± 4.5 μg/g; Zn 35.7 ± 3.5 μg/g) than in kidney (Cu 3.7 ± 1.1 μg/g; Zn 21.5 ± 2.7 μg/g). Cu levels also differed between juveniles and adults. We reviewed the literature reporting metal concentrations in beavers. Our results indicate metal contamination in beavers away from important industrial emission sources and suggest the natural environment should be regularly monitored to ensure their levels are below recommended, legal values. [ABSTRACT FROM AUTHOR]