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Human activity in African tropical rainforests continues to threaten wild mammals. Many rural communities are dependent on hunting, yet there is a widespread lack of baseline data on ecology and the sustainability of hunting. We investigated the impacts of human activity on mammal species composition and distributions within a community forest surrounding a village in the buffer zone of the Dja Biosphere Reserve in south-east Cameroon. We conducted a camera-trap survey in August–November 2017 and detected 24 mammal species, including Critically Endangered western lowland gorilla Gorilla gorilla gorilla, Endangered central African chimpanzee Pan troglodytes troglodytes and Endangered tree pangolin Phataginus tricuspis. We used occupancy analysis to explore relationships between indicators of human activity (distance to a road and the Reserve), habitat quality (distance to the river and tree cover) and the distributions of species. We found that the local distribution of threatened mammals was not apparently limited by human activity, and proximity to the road did not negatively influence occupancy for any species. However, most of the Reserve's large species were not detected, including the African forest elephant Loxodonta cyclotis and the largest ungulates, and the occupancy of two species commonly hunted for wild meat was positively correlated with distance from the village, indicating hunting may be unsustainable. Our results show that the community forest provides habitat for threatened species outside the Reserve and in close proximity to people. However, effective conservation management will require continued monitoring and research to determine whether current rates of hunting are sustainable.

1) Camera trapping allows scientists to study activity patterns of animals under natural conditions. However, comparisons of activity patterns across seasons or latitudes can be biased, because activity is often attuned to sunrise and sunset, the timing of which varies with latitude and season. Existing transformation methods to solve this problem have limitations. (2) Here, we explore whether and how activity patterns can be transformed more accurately using two alternative ‘double anchoring’ transformations – equinoctial and average anchoring – that anchor activity time to two chosen anchor points during the study period. (3) Using simulated noisy datasets mimicking species with either crepuscular, diurnal or cathemeral activity patterns, we compared the ability of different transformation methods to extract the latent pattern and activity levels under different study conditions. We found that average anchoring best retrieved the original diel activity pattern and yielded accurate estimates of activity level. Two alternative transformation methods – single anchoring and equinoctial anchoring – performed less well. Bias in estimates from using untransformed clock times was most marked (up to 2.5-fold over-estimation) for longer studies covering 4-5 months either side of an equinox at high latitude, and focusing on crepuscular species. (4) We applied the average anchoring method to 9 months of data on Red deer (Cervus elaphus), Wild boar (Sus scrofa) and Mouflon (Ovis amon musimon) activity as captured by camera traps in National Park Hoge Veluwe, the Netherlands. Average anchoring revealed more pronounced peaks of activity after sunset than was apparent from untransformed data in red deer and wild boar, but not for mouflon, a cathemeral species. Similarly, activity level was lower when calculated using average-anchored time for red deer and wild boar, but no difference was observed for mouflon. (5) We conclude that transformation of time might not be necessary at latitudes below 20°, or in studies with a duration of less than a month (below 40° latitude). For longer study periods and/or higher latitudes, average-anchoring resolves the problem of variable day length. Code is provided. The transformation functions are incorporated in the R-package ‘activity’.

Compared to emblematic large carnivores, less charismatic or smaller carnivore species often receive little conservation attention, despite facing increasing anthropogenic pressure, and their status being poorly understood across much of their range. We employed systematic camera trapping and spatially explicit capture-recapture modelling to estimate variation in population density of serval, striped hyaena and aardwolf across the mixed-use Ruaha-Rungwa landscape in southern Tanzania. Three sites were selected as representative of different habitat types, management strategies, and levels of anthropogenic pressure: Ruaha National Park’s core tourist area, dominated by Acacia-Commiphora bushlands and thickets; the Park’s miombo woodland; and the neighbouring community-run MBOMIPA Wildlife Management Area, also covered in Acacia-Commiphora.Our results show that the Park’s miombo woodlands supported a higher serval density than the core tourist area and Wildlife Management Area, with 5.56 [Standard Error = ±2.45], 3.45 [±1.04] and 2.08 [±0.74] individuals per 100 km2, respectively. This variation is likely driven by precipitation, the abundance of apex predators, and the level of anthropogenic pressure.Striped hyaena were detected only in the Wildlife Management Area and at low density (1.36 [±0.5] individuals per 100 km2), potentially due to the location of the surveyed sites at the edge of the species’ global range, high densities of sympatric competitors and anthropogenic edge effects.Finally, aardwolf were captured in both the Park’s core tourist area and the Wildlife Management Area, with a higher density in the Wildlife Management Area (13.25 [±2.48] versus 9.19 [±1.66] individuals per 100 km2), possibly as a result of lower intraguild predation and late fire outbreaks in the area surveyed.By shedding light on three understudied African carnivore species, this study highlights the importance of miombo woodland conservation and community-managed conservation, as well as the value of camera trap data to improve ecological knowledge of lesser-studied carnivores.

1.Population density estimations are essential for wildlife management and conservation. Camera traps have become a promising cost-effective tool, for which several methods have been described to estimate population density when individuals are unrecognizable (i.e. unmarked populations). However, comparative tests of their applicability and performance are scarce., 2.Here, we have compared three methods based on camera traps to estimate population density without individual recognition: Random Encounter Model (REM), Random Encounter and Staying Time (REST) and Distance Sampling with camera traps (CT-DS). Comparisons were carried out in terms of consistency with one another, precision and cost-effectiveness. We considered six natural populations with a wide range of densities, and three species with different behavioural traits (red deer Cervus elaphus, wild boar Sus scrofa and red fox Vulpes vulpes). In three of these populations, we obtained independent density estimates as a reference., 3. The densities estimated ranged from 0.23 individuals/km2 (fox) to 34.87 individuals/km2 (red deer). We did not find significant differences in terms of density values estimated by the three methods in five out of six populations, but REM has a tendency to generate higher average density values than REST and CT-DS. Regarding the independents’ densities, REM results were not significantly different in any population, and REST and CT-DS were significantly different in one population. The precision obtained was not significantly different between methods, with average coefficients of variation of 0.28 (REST), 0.36 (REM) and 0.42 (CT-DS). The REST method required the lowest human effort., 4. Synthesis and applications. Our results show that all of the methods examined can work well, with each having particular strengths and weaknesses. Broadly, Random Encounter and Staying Time (REST) could be recommended in scenarios of high abundance, Distance Sampling with camera traps (CT-DS) in those of low abundance while Random Encounter Model (REM) can be recommended when camera trap performance is not optimal, as it can be applied with less risk of bias. This broadens the applicability of camera trapping for estimating densities of unmarked populations using information exclusively obtained from camera traps. This strengthens the case for scientifically based camera trapping as a cost-effective method to provide reference estimates for wildlife managers, including within multi-species monitoring programmes., This work was partly funded by ENETWILD project (http://www.enetw ild.com). P.P. received support from the MINECO-UCLM through an FPU grant (FPU16/00039) and from the Society of Spanish Researches in the United Kingdom and UCLM through an ‘On the Move' grant.

Leopard (Panthera pardus) populations across Africa are increasingly exposed to high levels of anthropogenic disturbance, and information on habitat use responses of leopards in human-disturbed landscapes can help inform status assessments and guide conservation interventions. Unfortunately, however, few studies have investigated leopard ecology in human-disturbed landscapes, particularly in Africa. We employed camera-trapping and occupancy modelling to provide inferences on leopard habitat use in a National Park in Mozambique impacted by subsistence farming and bushmeat poaching. Replicated detection/non-detection occupancy surveys were used to estimate site use by leopards in a representative area of the park, and to investigate relative impacts of environmental, conspecific and anthropogenic factors on leopard occurrence. The proportion of sites used by leopards was estimated at 0.814 (SE = 0.093), which is approximately twice the occupancy previously reported for lion (44%) and cheetah (40%) in the same area. Leopard presence was not strongly predicted by any of the covariates, indicating there were no strong limiting factors. While leopards generally avoided human settlements and were positively predicted by prey, results suggest that there was sufficient prey and space for the species to use most available habitats. The greatest contributing factor to leopard habitat use was a positive correlation with bushmeat poachers and lions. It is possible that these other predators provide a more accurate indicator of prey availability than our single-species indicator based on camera trap data. This study provides important novel information on habitat use by leopards in a system disturbed by rural human subsistence activities in Africa.

Camera trapping is widely used in ecological studies to estimate animal density, although these studies are largely restricted to animals that can be identified to the individual level. The random encounter model, developed by Rowcliffe et al. (J Anal Ecol 45(4):1228–1236, 2008), estimates animal density from camera-trap data without the need to identify animals. Although the REM can provide reliable density estimates, it lacks the potential to account for the multiple sources of variance in the modelling process. The density estimator in REM is a ratio, and since the variance of a ratio estimator is intractable, we examine and compare the finite sample performance of many approaches for obtaining confidence intervals via simulation studies. We also propose an integrated random encounter model as a parametric alternative, which is flexible and can incorporate covariates and random effects. A data example from Whipsnade Wild Animal Park, Bedfordshire, south England, is used to demonstrate the application of these methods. Supplementary materials accompanying this paper appear on-line.

Activity range – the amount of time spent active per day – is a fundamental aspect contributing to the optimization process by which animals achieve energetic balance. Based on their size and the nature of their diet, theoretical expectations are that larger carnivores need more time active to fulfil their energetic needs than do smaller ones and also more time active than similar‐sized non‐carnivores. Despite the relationship between daily activity, individual range and energy acquisition, large‐scale relationships between activity range and body mass among wild mammals have never been properly addressed. This study aimed to understand the scaling of activity range with body mass, while controlling for phylogeny and diet. We built simple empirical predictions for the scaling of activity range with body mass for mammals of different trophic guilds and used a phylogenetically controlled mixed model to test these predictions using activity records of 249 mammal populations (128 species) in 19 tropical forests (in 15 countries) obtained using camera traps. Our scaling model predicted a steeper scaling of activity range in carnivores (0.21) with higher levels of activity (higher intercept), and near‐zero scaling in herbivores (0.04). Empirical data showed that activity ranges scaled positively with body mass for carnivores (0.061), which also had higher intercept value, but not for herbivores, omnivores and insectivores, in general, corresponding with the predictions. Despite the many factors that shape animal activity at local scales, we found a general pattern showing that large carnivores need more time active in a day to meet their energetic demands. Introduction Activity range – the amount of time, in hours, spent active per day – is a fundamental outcome of the complex physiological and behavioral optimization process by which animals ensure that energy input keeps pace with energy output. In addition to basal metabolism, animals face costs of foraging, acquiring mates and shelter, building reserves for lean times and escaping predators (Carbone et al. 2007, Halle and Stenseth 2012). Environmental and ecological factors that vary through the day (e.g. luminosity, temperature, predation risk and competition avoidance) constrain activity to certain times, depending on morpho‐physiological limitations (Castillo‐Ruiz et al. 2012, Hut et al. 2012). In addition, animals need time to rest in order to recover their cognitive or physical condition (Siegel 2005). Thus, they must optimize their activity range to meet their resource requirements, while dealing with natural daily cycles and saving time for sleep/rest (Downes 2001, Siegel 2005, Cozzi et al. 2012). The resource requirements of mammals are related to basal metabolic rate, which scales positively with body mass (Kleiber 1932, Isaac and Carbone 2010), while predation risk decreases with body mass (Sinclair et al. 2003, Hopcraft et al. 2009). Because high predation risk constrains activity while high resource needs increases activity range (Cozzi et al. 2012, Suselbeek et al. 2014), the question arises whether and how activity range also scales with body mass. Day range (total distance travelled in a day) and home range (area in which animals perform their daily activities) scales positively with body mass and are key metrics to understand the resource requirements of an animal (McNab 1963, Kelt and Van Vuren 2001, Carbone et al. 2005, Tamburello et al. 2015). As activity range is related to space‐use metrics (i.e. home range and day range), it is hence, also related to the acquisition of energy. Given that, one might expect activity range to increase with body mass. However, we have a poor understanding of how this relationship actually looks. Previous work developed predictions of body mass scaling with day range (Garland 1983, Carbone et al. 2005) and travel speed (Carbone et al. 2007, Rowcliffe et al. 2016). From a simple physical viewpoint, activity range should equal the day range divided by average travel speed. It should thus be possible to infer the scaling of activity range with body mass from these relationships. Some of the variation in space use across species that is not explained by body mass is associated with different evolutionary histories and ecological traits (McNab 1963, Kelt and Van Vuren 2001, Price and Hopkins 2015, Tamburello et al. 2015). Diet is the most conspicuous of these, because primary and secondary productivity present different overall yields and accessibility for consumers (Jetz et al. 2004), which in turn influence individual movements (Carbone et al. 2005) and potentially activity range, when exploiting resources at different trophic levels. The nature of the diet aggravates the higher energetic demands of larger carnivores. Predators have considerable energetic constraints related to hunting and handling their prey (Gorman et al. 1998, Carbone et al. 1999) as animal prey can be rare, widely dispersed, unpredictable in time and space and not storable (Jetz et al. 2004, Carbone et al. 2007). Therefore, carnivores have the lowest energy supply rates (supply rate of usable resources available inside the home range), independent of body mass, when compared to other diet categories (Jetz et al. 2004) besides exploring larger areas and traveling greater daily distances (McNab 1963, Kelt and Van Vuren 2001, Carbone et al. 2005, Tamburello et al. 2015). Therefore, larger animals occupy larger areas than small ones, and carnivores occupy larger areas than do similar‐sized non‐carnivores (Jetz et al. 2004, Tamburello et al. 2015). To date, few studies have considered interspecific variation in activity range with body mass and other species traits. For example, van Schaik and Griffiths (1996) and Gomez et al. (2005) anecdotally suggested that larger mammal species are cathemeral (i.e. active day and night), which implies that they can be active during a larger proportion of the 24‐h cycle. Rowcliffe et al. (2014) found that activity range is positively correlated with body mass in tropical forest mammals in Panama. Ramesh et al. (2015) found a negative relationship between body mass and activity concentration (i.e. how concentrated in few hours is the activity of an animal during the day) in Indian mammals, also equating to a positive association between activity range and body mass. However, no study has explored variation in activity range across a diverse range of species, while controlling for phylogeny and diet. This has been, at least in part, due to a lack of consistent data available on a wide range of species. Recent work using camera traps (Oliveira‐Santos et al. 2013, Rowcliffe et al. 2014), however, has demonstrated that accurate estimates of activity range can be obtained from photographic records from camera traps. Given the large and rapidly increasing volume of camera‐trapping data available globally (Burton et al. 2015), these approaches, consistently applied across a wide range of studies, can provide an important basis for the large‐scale study of activity. Here, we provided simple empirical predictions for the scaling of activity range with body mass for mammals of different trophic guilds. To test these predictions, we estimated the activity range for 249 populations of 128 terrestrial mammal species across 19 tropical forests, and used a phylogenetically controlled mixed model to determine how activity range scales with body mass by diet. As larger animals occupy larger areas than small ones, and carnivores occupy larger areas than do similar‐sized non‐carnivores (Jetz et al. 2004), we hypothesize that carnivores will present a higher scaling of activity range with body mass and also higher activity ranges for a given mass (higher intercept) when compared to herbivores, omnivores and insectivores.

Carnivores have long been used as model organisms to examine mechanisms that allow coexistence among ecologically similar species. Interactions between carnivores, including competition and predation, comprise important processes regulating local community structure and diversity. We use data from an intensive camera-trapping monitoring program across eight Neotropical forest sites to describe the patterns of spatiotemporal organization of a guild of five sympatric cat species: jaguar (Panthera onca), puma (Puma concolor), ocelot (Leopardus pardalis), jaguarundi (Herpailurus yagouaroundi) and margay (Leopardus wiedii). For the three largest cat species, we developed multi-stage occupancy models accounting for habitat characteristics (landscape complexity and prey availability) and models accounting for species interactions (occupancy estimates of potential competitor cat species). Patterns of habitat-use were best explained by prey availability, rather than habitat structure or species interactions, with no evidence of negative associations of jaguar on puma and ocelot occupancy or puma on ocelot occupancy. We further explore temporal activity patterns and overlap of all five felid species. We observed a moderate temporal overlap between jaguar, puma and ocelot, with differences in their activity peaks, whereas higher temporal partitioning was observed between jaguarundi and both ocelot and margay. Lastly, we conducted temporal overlap analysis and calculated species activity levels across study sites to explore if shifts in daily activity within species can be explained by varying levels of local competition pressure. Activity patterns of ocelots, jaguarundis and margays were similarly bimodal across sites, but pumas exhibited irregular activity patterns, most likely as a response to jaguar activity. Activity levels were similar among sites and observed differences were unrelated to competition or intraguild killing risk. Our study reveals apparent spatial and temporal partitioning for most of the species pairs analyzed, with prey abundance being more important than species interactions in governing the local occurrence and spatial distribution of Neotropical forest felids. © 2019 Santos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Living in groups comes with many potential benefits, especially for juveniles. Naïve individuals may learn how to forage, or avoid predators through group vigilance. Understanding these benefits, however, requires an appreciation of the opportunities juveniles have to associate with (and learn from) others. Here we describe social groups in terms of residency, movement, relatedness, and social associations from the perspective of juvenile hihi, a threatened New Zealand passerine bird. Over three years, we identified individuals in groups, their relatedness, and behavioural interactions. Using multistate analysis, we compared movement and residency of adults and juveniles and found that groups were composed predominately of juveniles which remained at group sites for longer than more transient adults. Movement of juveniles between groups did occur but was generally low. There was no evidence that siblings and parents were likely to be seen in groups together. With an initial understanding of group structure, we next asked what characteristics predicted assortment in social network associations. By identifying groups of co-occurring juveniles from time-stamped observations of individual hihi and building a social network, we found that juveniles were most likely to associate with other juveniles. Associations were also predominantly based on locations where hihi spent the most time, reflecting limited movement among separate groups. We suggest groups are best described as “gangs” where young hihi have little interaction with adults. These spatially-separated groups of juveniles may have consequences for social information use during the first few months of independence in young birds.

Hunting with snares is indiscriminate and wasteful, and this practice is currently one of the gravest threats to terrestrial vertebrates in the tropics. However, as snares are difficult to detect and often dispersed widely across large, inaccessible areas it is problematic to reliably estimate their prevalence and no standard survey methods exist. Conservation managers need reliable, timely, information on the spatio-temporal patterns of hunting and on responses to interventions, and we present an innovative sampling and analysis framework that allows for the rigorous estimation of snare detectability and ‘abundance’, but which can be feasibly implemented in challenging field contexts. This new approach was used to undertake a large-scale systematic snare survey in Keo Seima Wildlife Sanctuary, in Eastern Cambodia, and the resulting data were analysed using a novel application of N-mixture models. A range of environmental and management factors were examined as potential determinants of snare abundance and detectability, and proximity to the Vietnamese border was shown to be overwhelmingly the most influential factor. Snares were more common in the wet season rather than the dry season, and the detection probability of snares was shown to be low (~ 0.33), as predicted. No clear relationships between snaring levels, anti-poaching patrol effort and ungulate densities were evident from these data. There was clear evidence that certain factors, such as the percentage of dense forest cover, will exert confounding effects on both detectability and abundance, highlighting the critical need to take account of the imperfect detection when designing threat monitoring systems.

The availability of vertebrate hosts is a major determinant of the occurrence of ticks and tick-borne zoonoses in natural and anthropogenic ecosystems and thus drives disease risk for wildlife, livestock, and humans. However, it remains challenging to quantify the availability of vertebrate hosts in field settings, particularly for medium-sized to large-bodied mammals. Here, we present a method that uses camera traps to quantify the availability of warm-bodied vertebrates to ticks. The approach is to deploy camera traps at questing height at a representative sample of random points across the study area, measure the average photographic capture rate for vertebrate species, and then correct these rates for the effective detection distance. The resulting "passage rate" is a standardized measure of the frequency at which vertebrates approach questing ticks, which we show is proportional to contact rate. A field test across twenty 1-ha forest plots in the Netherlands indicated that this method effectively captures differences in wildlife assemblage composition between sites. Also, the relative abundances of three life stages of the sheep tick Ixodes ricinus from drag sampling were correlated with passage rates of deer, which agrees with the known association with this group of host species, suggesting that passage rate effectively reflects the availability of medium- to large-sized hosts to ticks. This method will facilitate quantitative studies of the relationship between densities of questing ticks and the availability of different vertebrate species-wild as well as domesticated species-in natural and anthropogenic settings.

Estimates of animal abundance are essential for understanding animal ecology. Camera traps can be used to estimate the abundance of terrestrial mammals, including elusive species, provided that the sensitivity of the sensor, estimated as the effective detection distance (EDD), is quantified. Here, we show how the EDD can be inferred directly from camera trap images by placing markers at known distances along the midline of the camera field of view, and then fitting distance-sampling functions to the frequency of animal passage between markers. EDD estimates derived from simulated passages using binned detection distances approximated those obtained from continuous detection distance measurements if at least five intervals were used over the maximum detection distance. A field test of the method in two forest types with contrasting vegetation density, with five markers at 2.5 m intervals, produced credible EDD estimates for 13 forest-dwelling mammals. EDD estimates were positively correlated with species body mass, and were shorter for the denser vegetation, as expected. Our findings suggest that this simple method can produce reliable estimates of EDD. These estimates can be used to correct photographic capture rates for difference in sampling effort resulting from differences in sensor sensitivity between species and habitats. Simplifying the estimation of EDD will result in less biased indices of relative abundance, and will also facilitate the use of camera trap data for estimating animal density.

Introduction: Wildlife is an important source of protein for many people in developing countries. Yet wildlife depletion due to overexploitation is common throughout the humid tropics and its effect on protein security, especially for vulnerable households, is poorly understood. This is problematic for both sustainable rural development and conservation management. Methods: This study investigates a key dimension of protein security in a cash-crop farming community living in a wildlife-depleted farm-forest landscape in SW Ghana, a region where protein–energy malnutrition persists. Specifically, we monitored protein sufficiency, defined as whether consumption met daily requirements, as benchmarked by recommended daily allowance (RDA). We focus on whether more vulnerable households were less likely to be able to meet their protein needs, where vulnerability was defined by wealth, agricultural season and gender of the household head. Our central hypothesis was: (a) vulnerable households are less likely to consume sufficient protein. In the context that most plant proteins were home-produced, so likely relatively accessible to all households, while most animal proteins were purchased, so likely less accessible to vulnerable households, we tested two further hypotheses: (b) vulnerable households depend more on plant protein to cover their protein needs; and (c) vulnerable households are less likely to earn sufficient cash income to meet their protein needs through purchased animal sources. Results: Between 14% and 60% of households (depending on plant protein content assumptions) consumed less than the RDA for protein, but neither protein consumption nor protein sufficiency co-varied with household vulnerability. Fish, livestock and food crops comprised 85% of total protein intake and strongly affected protein sufficiency. However, bushmeat remained an important protein source (15% of total consumption), especially during the post-harvest season when it averaged 26% of total protein consumption. Across the year, 89% of households experienced at least one occasion when they had insufficient income to cover their protein needs through animal protein purchases. The extent of this income shortage was highest during the lean season and among poorer households. Conclusions: These findings indicate that despite wildlife depletion, bushmeat continues to make a substantial contribution to protein consumption, especially during the agricultural lean season. Income shortages among farmers limit their ability to purchase bushmeat or its substitutes, suggesting that wildlife depletion may cause malnutrition.

There is increasing evidence that the global spread of the fungal pathogen Batrachochytrium dendrobatidis (Bd) has been facilitated by the international trade in amphibians. Bd was first detected in the UK in 2004, and has since been detected in multiple wild amphibian populations. Most amphibians imported into the UK for the pet trade from outside the European Union enter the country via Heathrow Animal Reception Centre (HARC), where Bd positive animals have been previously detected. Data on the volume, diversity and origin of imported amphibians were collected for 59 consignments arriving at HARC between November 2009 and June 2012, along with a surveillance study to investigate the prevalence of Bd in these animals. Forty three amphibian genera were recorded, originating from 12 countries. It was estimated that 5000 – 7000 amphibians are imported through HARC into the UK annually for the pet trade. Bd was detected in consignments from the USA and Tanzania, in six genera, resulting in an overall prevalence of 3.6%. This suggests that imported amphibians are a source of Bd within the international pet trade.

Travel speed (average speed of travel while active) and day range (average speed over the daily activity cycle) are behavioural metrics that influence processes including energy use, foraging success, disease transmission and human-wildlife interactions, and which can therefore be applied to a range of questions in ecology and conservation. These metrics are usually derived from telemetry or direct observations. Here, we describe and validate an entirely new alternative approach, using camera traps recording passing animals to measure movement paths at very fine scale. Dividing the length of a passage by its duration gives a speed observation, and average travel speed is estimated by fitting size-biased probability distributions to a sample of speed observations. Day range is then estimated as the product of travel speed and activity level (proportion of time spent active), which can also be estimated from camera-trap data. We field tested the procedure with data from a survey of terrestrial mammals on Barro Colorado Island, Panama. Travel speeds and day ranges estimated for 12 species scaled positively with body mass, and were higher in faunivores than in herbivores, patterns that are consistent with those obtained using independent estimates derived from tracked individuals. Comparisons of our day range estimates with independent telemetry-based estimates for three species also showed very similar values in absolute terms. We conclude that these methods are accurate and ready to use for estimating travel speed and day range in wildlife. Key advantages of the methods are that they are non-invasive, and that measurements are made at very high resolution in time and space, yielding estimates that are comparable across species and studies. Combined with emerging techniques in computer vision, we anticipate that these methods will help to expand the range of species for which we can estimate movement rate in the wild.

Camera trap surveys exclusively targeting features of the landscape that increase the probability of photographing one or several focal species are commonly used to draw inferences on the richness, composition and structure of entire mammal communities. However, these studies ignore expected biases in species detection arising from sampling only a limited set of potential habitat features. In this study, we test the influence of camera trap placement strategy on community-level inferences by carrying out two spatially and temporally concurrent surveys of medium to large terrestrial mammal species within Tanzania's Ruaha National Park, employing either strictly game trail-based or strictly random camera placements. We compared the richness, composition and structure of the two observed communities, and evaluated what makes a species significantly more likely to be caught at trail placements. Observed communities differed marginally in their richness and composition, although differences were more noticeable during the wet season and for low levels of sampling effort. Lognormal models provided the best fit to rank abundance distributions describing the structure of all observed communities, regardless of survey type or season. Despite this, carnivore species were more likely to be detected at trail placements relative to random ones during the dry season, as were larger bodied species during the wet season. Our findings suggest that, given adequate sampling effort (> 1400 camera trap nights), placement strategy is unlikely to affect inferences made at the community level. However, surveys should consider more carefully their choice of placement strategy when targeting specific taxonomic or trophic groups.

Several thousand terrestrial protected areas (PAs) lie on international boundaries. Because international boundaries can be focal points for trade, illegal activity and development, such PAs can be vulnerable to a range of anthropogenic threats. There is an increasing trend towards the erection of international boundary infrastructure (including fences, barriers and ditches) in many parts of the world, which may reduce the risk of these anthropogenic threats to some PAs. However this may restrict home range and access to resources for some native species. We sought to understand the impacts of these two different types of threat by using camera traps to measure the activity level of humans, native and invasive mammals in four US PAs on the Mexican international boundary. Comparisons were made between treatment areas with barriers and those without. Results showed that puma and coati were more likely to appear in treatment areas without barriers, whereas humans were not observed more frequently in one treatment area over another. The suggestion is that the intermittent fencing present in this part of the world does affect some native species, but does not necessarily restrict the movement of humans (including illegal migrants), who may negatively impact native species.

Foraging activity in animals reflects a compromise between acquiring food and avoiding predation. The risk allocation hypothesis predicts that prey animals optimize this balance by concentrating their foraging activity at times of relatively low predation risk, as much as their energy status permits, but empirical evidence is scarce. We used a unique combination of automated telemetry, manual radiotelemetry and camera trapping to test whether activity at high risk times declined with food availability as predicted in a Neotropical forest rodent, the Central American agouti, Dasyprocta punctata. We found that the relative risk of predation by the main predator, the ocelot, Leopardus pardalis, estimated as the ratio of ocelot to agouti activity on camera trap photographs, was up to four orders of magnitude higher between sunset and sunrise than during the rest of the day. Kills of radiotracked agoutis by ocelots during this high-risk period far exceeded expectations given agouti activity. Both telemetric monitoring of radio-tagged agoutis and camera monitoring of burrow entrances indicated that agoutis exited their burrows later at dawn, entered their burrows earlier at dusk and had lower overall activity levels when they lived in areas with higher food abundance. Thus, agoutis avoided activity during the high-risk period more strongly when access to food was higher. Our study provides quantitative empirical evidence of prey animals concentrating their activity at times of relatively low predation risk. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

The proliferation of camera-trapping studies has led to a spate of extensions in the known distributions of many wild cat species, not least in Borneo. However, we still do not have a clear picture of the spatial patterns of felid abundance in Southeast Asia, particularly with respect to the large areas of highly-disturbed habitat. An important obstacle to increasing the usefulness of camera trap data is the widespread practice of setting cameras at non-random locations. Non-random deployment interacts with non-random space-use by animals, causing biases in our inferences about relative abundance from detection frequencies alone. This may be a particular problem if surveys do not adequately sample the full range of habitat features present in a study region. Using camera-trapping records and incidental sightings from the Kalabakan Forest Reserve, Sabah, Malaysian Borneo, we aimed to assess the relative abundance of felid species in highly-disturbed forest, as well as investigate felid space-use and the potential for biases resulting from non-random sampling. Although the area has been intensively logged over three decades, it was found to still retain the full complement of Bornean felids, including the bay cat Pardofelis badia, a poorly known Bornean endemic. Camera-trapping using strictly random locations detected four of the five Bornean felid species and revealed inter- and intra-specific differences in space-use. We compare our results with an extensive dataset of >1,200 felid records from previous camera-trapping studies and show that the relative abundance of the bay cat, in particular, may have previously been underestimated due to the use of non-random survey locations. Further surveys for this species using random locations will be crucial in determining its conservation status. We advocate the more wide-spread use of random survey locations in future camera-trapping surveys in order to increase the robustness and generality of inferences that can be made.

Bushmeat is an important resource in the livelihoods of many rural communities in sub-Saharan Africa and may be a crucial safety-net for the most vulnerable households, especially during times of economic hardship. However, little is known about the impacts of wildlife depletion on these functions. This study quantifies the role of bushmeat in diversified rural household economies in a wildlife depleted forest-farm landscape in Ghana, assessing its importance overall, as well as differentiated by the relative vulnerability of households. Using repeat socioeconomic questionnaires (N=787) among 63 households over a one-year period, the following hypotheses were tested: (a) vulnerable households harvest more bushmeat; (b) bushmeat contributes a greater proportion of household production in vulnerable households; (c) bushmeat is more important for cash income than consumption in vulnerable households; and (d) bushmeat sales are more important for vulnerable households. The bushmeat harvest value averaged less than US$1.0 per day for 89% of households and comprised less than 7% of household production value. Household wealth and gender of the household head had little effect on the importance of bushmeat. However, bushmeat harvest and sales were highest during the agricultural lean season. Overall, most harvested bushmeat (64%) was consumed, enabling households to spend 30% less on meat/fish purchases. These findings suggest that, despite heavily depleted wildlife and diversified livelihoods, bushmeat continues to have an important role in rural livelihoods by acting as a safety net for income smoothing and reducing household expenditure during times of economic hardship.

There is a growing appreciation of the multiple social and nonsocial factors influencing the foraging behavior of social animals but little understanding of how these factors depend on habitat characteristics or individual traits. This partly reflects the difficulties inherent in using conventional statistical techniques to analyze multifactor, multicontext foraging decisions. Discrete-choice models provide a way to do so, and we demonstrate this by using them to investigate patch preference in a wild population of social foragers (chacma baboons Papio ursinus). Data were collected from 29 adults across two social groups, encompassing 683 foraging decisions over a 6-month period and the results interpreted using an information-theoretic approach. Baboon foraging decisions were influenced by multiple nonsocial and social factors and were often contingent on the characteristics of the habitat or individual. Differences in decision making between habitats were consistent with changes in interference-competition costs but not with changes in social-foraging benefits. Individual differences in decision making were suggestive of a trade-off between dominance rank and social capital. Our findings emphasize that taking a multifactor, multicontext approach is important to fully understand animal decision making. We also demonstrate how discrete-choice models can be used to achieve this.

Background Foraging in groups offers animals a number of advantages, such as increasing their likelihood of finding food or detecting and avoiding predators. In order for a group to remain together, there has to be some degree of coordination of behaviour and movement between its members (which may in some cases be initiated by a decision-making leader, and in other cases may emerge as an underlying property of the group). For example, behavioural synchronisation is a phenomenon where animals within a group initiate and then continue to conduct identical behaviours, and has been characterised for a wide range of species. We examine how a pair of animals should behave using a state-dependent approach, and ask what conditions are likely to lead to behavioural synchronisation occurring, and whether one of the individuals is more likely to act as a leader. Results The model we describe considers how the energetic gain, metabolic requirements and predation risks faced by the individuals affect measures of their energetic state and behaviour (such as the degree of behavioural synchronisation seen within the pair, and the value to an individual of knowing the energetic state of its colleague). We explore how predictable changes in these measures are in response to changes in physiological requirements and predation risk. We also consider how these measures should change when the members of the pair are not identical in their metabolic requirements or their susceptibility to predation. We find that many of the changes seen in these measures are complex, especially when asymmetries exist between the members of the pair. Conclusion Analyses are presented that demonstrate that, although these general patterns are robust, care needs to be taken when considering the effects of individual differences, as the relationship between individual differences and the resulting qualitative changes in behaviour may be complex. We discuss how these results are related to experimental observations, and how the model and its predictions could be extended. Background: Foraging in groups offers animals a number of advantages, such as increasing their likelihood of finding food or detecting and avoiding predators. In order for a group to remain together, there has to be some degree of coordination of behaviour and movement between its members (which may in some cases be initiated by a decision-making leader, and in other cases may emerge as an underlying property of the group). For example, behavioural synchronisation is a phenomenon where animals within a group initiate and then continue to conduct identical behaviours, and has been characterised for a wide range of species. We examine how a pair of animals should behave using a state-dependent approach, and ask what conditions are likely to lead to behavioural synchronisation occurring, and whether one of the individuals is more likely to act as a leader. Results: The model we describe considers how the energetic gain, metabolic requirements and predation risks faced by the individuals affect measures of their energetic state and behaviour (such as the degree of behavioural synchronisation seen within the pair, and the value to an individual of knowing the energetic state of its colleague). We explore how predictable changes in these measures are in response to changes in physiological requirements and predation risk. We also consider how these measures should change when the members of the pair are not identical in their metabolic requirements or their susceptibility to predation. We find that many of the changes seen in these measures are complex, especially when asymmetries exist between the members of the pair. Conclusion: Analyses are presented that demonstrate that, although these general patterns are robust, care needs to be taken when considering the effects of individual differences, as the relationship between individual differences and the resulting qualitative changes in behaviour may be complex. We discuss how these results are related to experimental observations, and how the model and its predictions could be extended.

Mammalian carnivores fall into two broad dietary groups: smaller carnivores (20 kg) that specialize in feeding on large vertebrates. We develop a model that predicts the mass-related energy budgets and limits of carnivore size within these groups. We show that the transition from small to large prey can be predicted by the maximization of net energy gain; larger carnivores achieve a higher net gain rate by concentrating on large prey. However, because it requires more energy to pursue and subdue large prey, this leads to a 2-fold step increase in energy expenditure, as well as increased intake. Across all species, energy expenditure and intake both follow a three-fourths scaling with body mass. However, when each dietary group is considered individually they both display a shallower scaling. This suggests that carnivores at the upper limits of each group are constrained by intake and adopt energy conserving strategies to counter this. Given predictions of expenditure and estimates of intake, we predict a maximum carnivore mass of approximately a ton, consistent with the largest extinct species. Our approach provides a framework for understanding carnivore energetics, size, and extinction dynamics., Author Summary Carnivores fall into two dietary groups based on the energetic requirements of their feeding strategies: small-bodied species, which feed mostly on prey smaller than themselves, and large-bodied species, which prefer prey around their own size. While carnivores around the size of a lynx or larger can obtain higher net energy intake by switching to relatively large prey, the difficulty of catching and subduing these animals means that a large-prey specialist would expend twice as much energy as a small-prey specialist of equivalent body size. Analyzing the balance between energy intake and expenditure across a range of species, we predict that mammalian carnivores should have a maximum body mass of one ton. Thus, mammalian carnivores are relatively small compared with the largest extinct terrestrial herbivorous mammals, such as the Indricothere, which weighed around 15 tons. The largest existing carnivore, the polar bear, is only around half a ton, while the largest known extinct carnivores, such as the short-faced bear, weighed around one ton. This study suggests that those extremely large carnivores would have been heavily reliant on abundant large prey, helping to explain why the largest modern mammalian carnivores are rare and vulnerable to extinction., A simple theoretical model provides a framework to understand carnivore energy budgets and reveals insights into the evolution of body size in mammalian carnivores.