Camera Traps Research Articles

First record of albinism in long-nosed mongoose Xenogale naso documented with camera traps in the Yoko Council Forest, Centre Cameroon

Abstract Color mutations are a common phenomenon in vertebrates. Among these anomalies, albinism is the most common in wild mammals. We deployed 78 camera traps across the Yoko Council Forest (YCF) to inventory medium to large-sized terrestrial mammals and we obtained a total effort of 17,981 operational camera trap days, giving 169 detections of long-nosed mongoose. During this study, we obtained two independent detections of albino long-nosed mongooses (Xenogale naso). To our knowledge, this is the first report of albinism in this taxon.

Gentrification drives patterns of alpha and beta diversity in cities

While there is increasing recognition that social processes in cities like gentrification have ecological consequences, we lack nuanced understanding of the ways gentrification affects urban biodiversity. We analyzed a large camera trap dataset of mammals (>500 g) to evaluate how gentrification impacts species richness and community composition across 23 US cities. After controlling for the negative effect of impervious cover, gentrified parts of cities had the highest mammal species richness. Change in community composition was associated with gentrification in a few cities, which were mostly located along the West Coast. At the species level, roughly half (11 of 21 mammals) had higher occupancy in gentrified parts of a city, especially when impervious cover was low. Our results indicate that the impacts of gentrification extend to nonhuman animals, which provides further evidence that some aspects of nature in cities, such as wildlife, are chronically inaccessible to marginalized human populations.

Camera trap surveys of Atlantic Forest mammals: A data set for analyses considering imperfect detection (2004-2020).

Camera traps became the main observational method of a myriad of species over large areas. Data sets from camera traps can be used to describe the patterns and monitor the occupancy, abundance, and richness of wildlife, essential information for conservation in times of rapid climate and land-cover changes. Habitat loss and poaching are responsible for historical population losses of mammals in the Atlantic Forest biodiversity hotspot, especially for medium to large-sized species. Here we present a data set from camera trap surveys of medium to large-sized native mammals (>1 kg) across the Atlantic Forest. We compiled data from 5380 ground-level camera trap deployments in 3046 locations, from 2004 to 2020, resulting in 43,068 records of 58 species. These data add to existing data sets of mammals in the Atlantic Forest by including dates of camera operation needed for analyses dealing with imperfect detection. We also included, when available, information on important predictors of detection, namely the camera brand and model, use of bait, and obstruction of camera viewshed that can be measured from example pictures at each camera location. Besides its application in studies on the patterns and mechanisms behind occupancy, relative abundance, richness, and detection, the data set presented here can be used to study species' daily activity patterns, activity levels, and spatiotemporal interactions between species. Moreover, data can be used combined with other data sources in the multiple and expanding uses of integrated population modeling. An R script is available to view summaries of the data set. We expect that this data set will be used to advance the knowledge of mammal assemblages and to inform evidence-based solutions for the conservation of the Atlantic Forest. The data are not copyright restricted; please cite this paper when using the data.

Notes on the ecology, activity patterns and behavior of the kinkajou (Potos flavus)

Abstract Kinkajous are one of the most widely distributed Neotropical mammals, nonetheless, their nocturnal habits have posed challenges on the study of their ecology and behavior. Here, we used arboreal camera trapping in a pristine Amazonian forest in Ecuador, and ad libitum data from direct encounters in a lowland and a highland forest in Colombia to describe their activity patterns and describe anecdotal data on their diet and reproductive behaviors. As expected, kinkajous are strictly nocturnal and seem to be active throughout the entire night, although in our study there was less activity towards the beginning and the end of the night. Kinkajous were observed to be mostly solitary, rarely in groups of two to three adult individuals. Although their diet has not been described in detail, fruits from Moraceae and Urticaceae appear to be important components of their diet. Their reproductive behavior involves an isolated pair of kinkajous, and may be interrupted by other males. Pairs seem to meet for reproductive purposes and range together for several hours, during which courtship may take place, ending in copulation, which lasts for approximately 3 min. After copulation, the male and female appear to separate and return to their solitary habits. The results of this study complement the scarce information on the elusive kinkajous in the Neotropical forests.

Population Viability Analysis on Chinese Goral Indicates an Extinction Risk for a Local Population in Beijing, China.

The Chinese goral (Naemorhedus griseus) is identified as a vulnerable species on the Red List of China's Biodiversity and listed as a national second-class key protected wild animal in China. It is a representative flagship ungulate in Beijing. Its distribution range is fragmented and small populations are separated by dense infrastructures and tourism sites. Understanding its population status provides a foundation to plan effective conservation strategies. In this study, a population viability analysis was conducted with VORTEX (10.5.6.0) on a Chinese goral population in Beijing Yunmengshan Nature Reserve with the data collected by camera trapping and parameters referenced from other goral populations. The results show that this population will initially increase in the next 20 years and then decrease with a 32% probability of extinction risk. Supplementation with four adults, two females and two males, every 10 years would help minimize the extinction risk of this population. The results highlight the vital limiting factors for Chinese goral, including the initial population size, sex ratio at birth and mortality of infants (especially female infants). To improve the protection efficiency, detailed population parameters should be further acquired through continuous monitoring of this population. A thorough large-scale study should be carried out on other segregated goral populations in Beijing to facilitate the recovery of this endangered species.

Comparing local ecological knowledge with camera trap data to study mammal occurrence in anthropogenic landscapes of the Garden Route Biosphere Reserve

AbstractAccurate information on wildlife occurrence in anthropogenic landscapes is essential to develop effective conservation measures. Monitoring multiple mammal species in heterogeneous landscapes can be challenging because of the diversity of land‐uses and species behaviors. Therefore, different monitoring methods are better adapted to different contexts. We compared data obtained from camera traps with data gathered through an online survey to document the presence of mammal species in mosaic landscapes of the Garden Route Biosphere Reserve in South Africa. The survey detected the same 15 species as the camera traps as well as the additional common duiker. Both methods effectively detected most large mammal species, whereas results were less consistent for smaller species and carnivores. Combining the two methods enabled us to produce more robust estimates of species absence and confirm species presence reported by survey respondents. In less disturbed areas, respondents with good ecological knowledge were effective at monitoring mammal species, while extending the spatial coverage of the study. Bearing in mind the limitations of each method, camera traps and an online survey could complement each other if combined. Together, they can provide a more comprehensive understanding of mammal communities in anthropogenic landscapes, increasing both spatial coverage and the number of species sightings.

A Low‐Cost Small‐Mammal Camera Trap for Research and Education

A Low‐Cost Small‐Mammal Camera Trap for Research and Education

Correction to: Establishing a baseline of mammal diversity in Kali Tiger Reserve, India through camera trapping

Correction to: Establishing a baseline of mammal diversity in Kali Tiger Reserve, India through camera trapping

Body mass mediates spatio-temporal responses of mammals to human frequentation across Italian protected areas.

Protected area (PA) networks are a pivotal tool to fight biodiversity loss, yet they often need to balance the mission of nature conservation with the socio-economic need of giving opportunity for outdoor recreation. Recreation in natural areas is important for human health in an urbanized society, but can prompt behavioural modifications in wild animals. Rarely, however, have these responses being studied across multiple PAs and using standardized methods. We deployed a systematic camera trapping protocol at over 200 sites to sample medium and large mammals in four PAs within the European Natura 2000 network to assess their spatio-temporal responses to human frequentation, proximity to towns, amount of open habitat and topographical variables. By applying multi-species and single-species models for the number of diurnal, crepuscular and nocturnal detections and a multi-species model for nocturnality index, we estimated both species-specific- and meta-community-level effects, finding that increased nocturnality appeared the main strategy that the mammal meta-community used to cope with human disturbance. However, responses in the diurnal, crepuscular and nocturnal site use were mediated by species' body mass, with larger species exhibiting avoidance of humans and smaller species more opportunistic behaviours. Our results show the effectiveness of standardized sampling and provide insights for planning the expansion of PA networks as foreseen by the Kunming-Montreal biodiversity agreement.

Mesocarnivores vary in their spatiotemporal avoidance strategies at communications hubs of an apex carnivore.

Mesocarnivores face interspecific competition and risk intraguild predation when sharing resources with apex carnivores. Within a landscape, carnivores across trophic levels may use the same communication hubs, which provide a mix of risks (injury/death) and rewards (gaining information) for subordinate species. We predicted that mesocarnivores would employ different strategies to avoid apex carnivores at shared communication hubs, depending on their trophic position. To test our prediction, we examined how different subordinate carnivore species in the Santa Cruz Mountains of California, USA, manage spatial overlap with pumas (Puma concolor), both at communication hubs and across a landscape-level camera trap array. We estimated species-specific occurrence, visitation rates, temporal overlap, and Avoidance-Attraction Ratios from camera traps and tested for differences between the two types of sites. We found that mesocarnivores generally avoided pumas at communication hubs, and this became more pronounced when pumas scent-marked during their most recent visit. Coyotes (Canis latrans), the pumas' closest subordinate competitor in our system, exhibited the strongest avoidance at communication hubs. Gray foxes (Urocyon cinereoargenteus) avoided pumas the least, which may suggest possible benefits from pumas suppressing coyotes. Overall, mesocarnivores exhibited various spatiotemporal avoidance strategies at communication hubs rather than outright avoidance, likely because they benefit from information gained while 'eavesdropping' on puma activity. Variability in avoidance strategies may be due to differential predation risks, as apex carnivores often interact more aggressively with their closest competitors. Combined, our results show how apex carnivores trigger complex species interactions across the entire carnivore guild and how trophic position determines behavioral responses and subsequent space use of subordinate mesocarnivores across the landscape.

Shifting mammal communities and declining species richness along an elevational gradient on Mount Kenya.

Conservation areas encompassing elevation gradients are biodiversity hotspots because they contain a wide range of habitat types in a relatively small space. Studies of biodiversity patterns along elevation gradients, mostly on small mammal or bird species, have documented a peak in diversity at mid elevations. Here, we report on a field study of medium and large mammals to examine the impact of elevation, habitat type, and gross primary productivity on community structure. Species richness was observed using a camera trap transect with 219 sites situated across different habitat types from 2329 to 4657 m above the sea level on the western slope of Mt Kenya, the second highest mountain in Africa. We found that the lowest elevation natural habitats had the highest species richness and relative abundance and that both metrics decreased steadily as elevation increased, paralleling changes in gross primary productivity, and supporting the energy richness hypothesis. We found no evidence for the mid-domain effect on species diversity. The lowest elevation degraded Agro-Forestry lands adjacent to the National Park had high activity of domestic animals and reduced diversity and abundance of native species. The biggest difference in community structure was between protected and unprotected areas, followed by more subtle stepwise differences between habitats at different elevations. Large carnivore species remained relatively consistent but dominant herbivore species shifted along the elevation gradient. There was some habitat specialization and turnover in species, such that the elevation gradient predicts a high diversity of species, demonstrating the high conservation return for protecting mountain ecosystems for biodiversity conservation.

Spicing up oak forest restoration: a preliminary report of the protective use of chili peppers in direct seeding of acorns

Direct sowing of acorns is a technique for oak forest restoration, however, high seed predation by mammals can occur and cost‐effective alternatives to protect acorns are therefore required. The present study evaluated the protection provided by chili peppers (Capsicum annuum and Capsicum pubescens) to acorns of Quercus germana, an endangered endemic oak tree of the cloud forests. Greenhouse and field experiments were established to evaluate the effect of chili peppers on acorn removal, germination, and seedling emergence. These processes were related to the prevalent microhabitat characteristics where the acorns were introduced, and the fauna that consumed chili peppers and acorns was identified using camera traps. In the greenhouse trial, more seedlings emerged from acorns covered by fruits of C. pubescens (65.71 ± 8.14) and C. annuum (57.14 ± 8.49%) compared to unprotected acorns (31.43 ± 7.96%). Contrary to expectation, acorn removal in the field was greater using C. pubescens than the unprotected acorns, particularly in microsites with lower tree cover and higher grass dominance. Acorn removal was similar to chili pepper treatments. These results are explained by the camera trap records, which showed bird species consuming Capsicum fruits, thus exposing the acorns to subsequent removal and/or consumption by rodents. The studied Capsicum fruits had no negative effect on acorn germination and seedling emergence under greenhouse conditions, and future practices could, therefore, involve the use of different techniques to prevent the discovery of chili peppers by birds; for example, using green chili peppers for camouflage, or hiding them under litter or herbaceous vegetation.

Camera-traps detect the maned wolf preying on broad-snouted caiman eggs

The maned wolf (Chrysocyon brachyurus) is a South-American canid of which conservation guidelines have been implemented due to its population vulnerability. Its trophic ecology demonstrates an omnivorous and opportunistic diet, and even flexibility in response to anthropogenic disturbances. Among the food items identified, the consumption of reptiles is scarce, and includes snakes and lizards. We monitored broad-snouted caiman (Caiman latirostris) nests during four nesting seasons through camera trapping, in savannas and grasslands areas, and recorded maned wolves feeding on caiman eggs during periods of drought. The consumption of an uncommon item, even at low frequency, suggests that camera trapping could become a complementary tool for studying the dietary habits of the maned wolf. Caimans have been a priority for conservation, while maned wolves are currently being released and reintroduced in order to reverse their vulnerable population status. This trophic interaction must be monitored in the long term, to project integral conservation strategies that include both emblematic species.

Integrating presence‐only and detection/non‐detection data to estimate distributions and expected abundance of difficult‐to‐monitor species on a landscape‐scale

Abstract Estimating species distribution and abundance is foundational to effective management and conservation. Using an integrated species distribution model that combines presence‐only data from various sources with detection/non‐detection data from structured surveys, we estimated the distribution and expected abundance of three difficult‐to‐monitor mammals of management concern across New York State, namely, coyotes (Canis latrans), bobcats (Lynx rufus) and black bears (Ursus americanus). Three distinct landscape‐scale camera trap surveys provided detection/non‐detection data over 9 years between 2013 and 2021, and we augmented those data with incidental records of our focal species from public repositories. We used an inhomogeneous Poisson point process to construct an integrated model that fit both data types simultaneously. We demonstrate a simple application of spatial point density of all species records in the accessed public databases to inform the thinning process to account for unknown spatial sampling in the presence‐only data, often referred to as the ‘magic covariate’. Using this approach, we examine habitat associations and provide spatially explicit estimates in expected abundance across the entirety of New York State for all three focal species. As expected, coyotes were the most widely distributed and abundant species, with a strong positive association with agricultural land uses. Bobcats exhibited low expected abundance throughout the state and showed positive associations with deciduous forest and forest edge, and a negative association with road density. Finally, we observed considerable spatial variation in abundance of black bears with expected abundance increasing in association with various forest cover and composition covariates and decreasing with crop cover. We present insights into habitat associations and spatial variation in abundance, and provide management implications for each of the species of interest. Synthesis and applications. Our integrated modelling method allows for managers to use citizen sightings combined with detection/non‐detection surveys to estimate robust indices of abundance for both high‐ and low‐density, and wide‐spread versus patchily distributed species. Through comparison with previous studies, we highlight how broad‐scale programmes, such as the statewide efforts to estimate species distributions undertaken here, can benefit substantively from integrated models that leverage additional data (here, incidental records) from a larger region of space, and thus capture more landscape heterogeneity than is plausible within formalized surveys alone.

Food Habits of the Common Palm Civet (Paradoxurus hermaphroditus) in Pangandaran Nature Reserve, West Java, Indonesia: a Preliminary Report

We conducted a preliminary survey of the wild common palm civet Paradoxurus hermaphroditus in a secondary forest in Pangandaran Nature Reserve, West Java, Indonesia. We collected 125 fresh fecal samples between October 2018 and August 2019. We conducted faecal analyses after species confirmation by camera trapping and faecal DNA analysis. Almost all faeces contained fruits and seeds (frequency of occurrence: 97.6%), while the percentage of animal matter (including mammals, birds, insects, non-insect arthropods, and molluscs) was much lower (22.4%). We observed no seasonal differences in major faecal contents. Higher dependence on fruits by the common palm civets was similar to those in other study sites. Seeds of at least eight different plant species were found in the faeces of the common palm civets, which implied that the common palm civets would play roles as seed dispersal agents.

Geographic differences in body size distributions underlie food web connectance of tropical forest mammals

Understanding variation in food web structure over large spatial scales is an emerging research agenda in food web ecology. The density of predator–prey links in a food web (i.e., connectance) is a key measure of network complexity that describes the mean proportional dietary breadth of species within a food web. Connectance is a critical component of food web robustness to species loss: food webs with lower connectance have been shown to be more susceptible to secondary extinctions. Identifying geographic variation in food web connectance and its drivers may provide insight into community robustness to species loss. We investigated the food web connectance of ground-dwelling tropical forest mammal communities in multiple biogeographic regions to test for differences among regions in food web connectance and to test three potential drivers: primary productivity, contemporary anthropogenic pressure, and variation in mammal body mass distributions reflective of historical extinctions. Mammal communities from fifteen protected forests throughout the Neo-, Afro-, and Asian tropics were identified from systematic camera trap arrays. Predator–prey interaction data were collected from published literature, and we calculated connectance for each community as the number of observed predator–prey links relative to the number of possible predator–prey links. We used generalized linear models to test for differences among regions and to identify the site level characteristics that best predicted connectance. We found that mammal food web connectance varied significantly among continents and that body size range was the only significant predictor. More possible predator–prey links were observed in communities with smaller ranges in body size and therefore sites with smaller body size ranges had higher mean proportional dietary breadth. Specifically, mammal communities in the Neotropics and in Madagascar had significantly higher connectance than mammal communities in Africa. This geographic variation in contemporary mammalian food web structure may be the product of historical extinctions in the Late Quaternary, which led to greater losses of large-bodied species in the Neotropics and Madagascar thus contributing to higher average proportional dietary breadth among the remaining smaller bodied species in these regions.

Evolutionary history and environmental variability structure contemporary tropical vertebrate communities

AbstractAimTropical regions harbour over half of the world's mammals and birds, but how their communities have assembled over evolutionary timescales remains unclear. To compare eco‐evolutionary assembly processes between tropical mammals and birds, we tested how hypotheses concerning niche conservatism, environmental stability, environmental heterogeneity and time‐for‐speciation relate to tropical vertebrate community phylogenetic and functional structure.LocationTropical rainforests worldwide.Time periodPresent.Major taxa studiedGround‐dwelling and ground‐visiting mammals and birds.MethodsWe used in situ observations of species identified from systematic camera trap sampling as realized communities from 15 protected tropical rainforests in four tropical regions worldwide. We quantified standardized phylogenetic and functional structure for each community and estimated the multi‐trait phylogenetic signal (PS) in ecological strategies for the four regional species pools of mammals and birds. Using linear regression models, we test three non‐mutually exclusive hypotheses by comparing the relative importance of colonization time, palaeo‐environmental changes in temperature and land cover since 3.3 Mya, contemporary seasonality in temperature and productivity and environmental heterogeneity for predicting community phylogenetic and functional structure.ResultsPhylogenetic and functional structure showed non‐significant yet varying tendencies towards clustering or dispersion in all communities. Mammals had stronger multi‐trait PS in ecological strategies than birds (mean PS: mammal = 0.62, bird = 0.43). Distinct dominant processes were identified for mammal and bird communities. For mammals, colonization time and elevation range significantly predicted phylogenetic clustering and functional dispersion tendencies respectively. For birds, elevation range and contemporary temperature seasonality significantly predicted phylogenetic and functional clustering tendencies, respectively, while habitat diversity significantly predicted functional dispersion tendencies.Main conclusionsOur results reveal different eco‐evolutionary assembly processes structuring contemporary tropical mammal and bird communities over evolutionary timescales that have shaped tropical diversity. Our study identified marked differences among taxonomic groups in the relative importance of historical colonization and sensitivity to environmental change.

Contribution of community monitoring to knowledge of mammal diversity in voluntarily conservation areas in Southern Mexico

In southern Mexico, Voluntarily Designated Conservation Areas (VCA) represent a biological conservation strategy wherein governance and management are entrusted to the territory. Within the VCAs of the La Chinantla region in the state of Oaxaca, Mexico, community monitoring utilizing camera traps has been conducted with the assistance of government programs. This initiative has yielded a substantial number of records for medium and large mammals. Nevertheless, the available information has not undergone systematic analysis, constraining its utility in strategic planning and the evaluation of biodiversity conservation endeavors. This study seeks to highlight the impact of community monitoring in 18 VCAs on understanding the altitudinal distribution of mammal diversity in La Chinantla. The analysis incorporates data from a community monitoring covering 129 camera trap stations (4,384 camera days) strategically positioned along an elevation gradient ranging from 50 to 2000 m above sea level, over the period 2011–2014. We assessed alpha and beta diversity, as well as the community structure of medium and large mammals within three distinct elevation zones. A total of 26 species of medium-sized mammals were documented, revealing distinct mammal assemblages in each zone. However, 15 species were common across all zones. We found that the highest species richness was observed below 400 m, where tropical rainforest vegetation predominates. We also found that the species turnover component had a significant impact on the total beta value. Despite the considerable involvement of local residents in the monitoring program and their acquisition of social, technical, and ecological knowledge, there is still a need to strengthen their capabilities to enhance community monitoring. Finally, fostering collaboration between local communities, academic institutions, and governmental initiatives is essential for the successful conservation of mammals in La Chinanlta.

Intraguild interactions and abiotic conditions mediate occupancy of mammalian carnivores: co‐occurrence of coyotes–fishers–martens

The widespread eradication of large carnivores and subsequent expansion of top mesopredators has the potential to impact species and community interactions with ecosystem‐wide implications. An example of these trophic dynamics is the widespread establishment of coyotes following extirpation of wolves and mountain lions in eastern North America. Here, we examined occupancy of three carnivores in northern New York considering both environmental/habitat factors and interspecific interactions. We estimated the co‐occurrence of coyotes, fishers, and martens from a landscape‐scale winter camera trap survey repeated annually for three years. Martens occurred independently of both coyotes and fishers, while fishers and coyotes displayed positive intraguild interactions that were constant across the landscape. Both marten and fisher first‐order occupancy were driven by a combination of biotic and abiotic factors, with both species displaying positive associations with forest cover but antithetical responses to average snow depth. The integral and antithetical role of snow depth in driving the occurrence of martens (positive) and fishers (negative) in the landscape indicates that future climatic warming could reduce the availability of current spatial refuges for martens created by severe winter conditions. Climate‐driven alterations to established competitive interactions and co‐existence patterns between marten and fisher have critical implications for the species survival and conservation. We provide correlational evidence consistent with the potential for positive top‐down effects of dominant mesocarnivores on subordinate species, with fisher occupancy increasing conditional on the presence of coyotes across the landscape. These findings align with the hypothesis that under certain conditions, coyotes may facilitate certain subordinate carnivores. The evidence produced here is consistent with hypotheses on the dynamic nature of trophic niches. We demonstrate the need to consider the interplay between climate, habitat, and interspecific interactions to understand wildlife occupancy patterns and inform wildlife management in a rapidly changing world.

Mammal responses to global changes in human activity vary by trophic group and landscape.

Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human-wildlife interactions along gradients of human influence.