scholarly journals Abundance and density estimates for common leopard Panthera pardus and clouded leopard Neofelis nebulosa in Manas National Park, Assam, India

Oryx ◽  
2013 ◽  
Vol 48 (1) ◽  
pp. 149-155 ◽  
Author(s):  
Jimmy Borah ◽  
Tridip Sharma ◽  
Dhritiman Das ◽  
Nilmani Rabha ◽  
Niraj Kakati ◽  
...  
Keyword(s):  
National Park ◽  
Camera Traps ◽  
Camera Trapping ◽  
Spatially Explicit ◽  
Panthera Pardus ◽  
Density Estimates ◽  
Clouded Leopard ◽  
Neofelis Nebulosa ◽  
Capture Recapture ◽  
The Common

AbstractEffective conservation of rare carnivores requires reliable estimates of population density for prioritizing investments and assessing the effectiveness of conservation interventions. We used camera traps and capture–recapture analysis to provide the first reliable abundance and density estimates for the common leopard Panthera pardus and clouded leopard Neofelis nebulosa in Manas National Park, India. In 57 days of camera trapping, with a total of 4,275 camera-trap days, we photo-captured 27 individually identified common leopards (11 males, 13 females and three unidentified), and 16 clouded leopards (four males, five females and seven unidentified). The abundance estimates using the Mh jackknife and Pledger model Mh were 47.0 and 35.6, respectively, for the common leopard, and 21.0 and 25.0, respectively, for the clouded leopard. Density estimates using maximum likelihood spatially-explicit capture–recapture were 3.4 ± SE 0.82 and 4.73 ± SE 1.43 per 100 km2 for the common and clouded leopards, respectively. Spatially-explicit capture–recapture provided more realistic density estimates compared with those obtained from conventional methods. Our data indicates that camera trapping using a capture–recapture framework is an effective tool for assessing population sizes of cryptic and elusive carnivores such as the common and clouded leopards. The study has established a baseline for the long-term monitoring programme for large carnivores in Manas National Park.

Spatially explicit capture–recapture analysis of bobcat (Lynx rufus) density: implications for mesocarnivore monitoring

2015 ◽  
Vol 42 (5) ◽  
pp. 394 ◽  
Author(s):  
Daniel H. Thornton ◽  
Charles E. Pekins
Keyword(s):  
Density Estimation ◽  
Large Scale ◽  
Local Density ◽  
Camera Traps ◽  
Camera Trapping ◽  
Lynx Rufus ◽  
Spatially Explicit ◽  
Density Estimates ◽  
Capture Recapture ◽  
Study Sites

Context Accurate density estimation is crucial for conservation and management of elusive species. Camera-trapping may provide an efficient method for density estimation, particularly when analysed with recently developed spatially explicit capture–recapture (SECR) models. Although camera-traps are employed extensively to estimate large carnivore density, their use for smaller carnivores has been limited. Moreover, while camera-trapping studies are typically conducted at local scales, the utility of analysing larger-scale patterns by combining multiple camera studies remains poorly known. Aims The goal of the present study was to develop a better understanding of the utility of SECR models and camera-trapping for the estimation of density of small carnivores at local and regional scales. Methods Based on data collected from camera-traps, we used SECR to examine density of bobcats (Lynx rufus) at four study sites in north-central Texas. We then combined our density estimates with previous estimates (from multiple methodologies) across the bobcat’s geographic range, and used linear regression to examine drivers of range-wide density patterns. Key results Bobcat densities averaged 13.2 per 100 km2 across all four study sites, and were lowest at the site in the most heavily modified landscape. Bobcat capture probability was positively related to forest cover around camera-trap sites. At the range-wide scale, 53% of the variation in density was explained by just two factors: temperature and longitude. Conclusions Our results demonstrate the utility of camera-traps, combined with SECR, to generate precise density estimates for mesocarnivores, and reveal the negative effects of landscape disturbance on bobcat populations. The associations revealed in our range-wide analysis, despite variability in techniques used to estimate density, demonstrate how a combination of multiple density estimates for a species can be used for large-scale inference. However, improvement in our understanding of biogeographic density patterns for mesocarnivores could be obtained from a greater number of camera-based density estimates across the range of a species, combined with meta-analytic techniques. Implications Camera-trapping and SECR should be more widely applied to generate local density estimates for many small and medium-sized carnivores, where at least a portion of the individuals are identifiable. If such estimates are more widely obtained, meta-analytic techniques could be used to test biogeographic predictions or for large-scale monitoring efforts.

scholarly journals Identifying individual cougars (Puma concolor) in remote camera images – implications for population estimates

2018 ◽  
Vol 45 (3) ◽  
pp. 274 ◽  
Author(s):  
Peter D. Alexander ◽  
Eric M. Gese
Keyword(s):  
Puma Concolor ◽  
Camera Traps ◽  
Camera Trapping ◽  
Field Methods ◽  
Density Estimates ◽  
North West ◽  
Photo Identification ◽  
Matching Process ◽  
Capture Recapture ◽  
Remote Camera

Context Several studies have estimated cougar (Puma concolor) abundance using remote camera trapping in conjunction with capture–mark–recapture (CMR) type analyses. However, this methodology (photo-CMR) requires that photo-captured individuals are individually recognisable (photo identification). Photo identification is generally achieved using naturally occurring marks (e.g. stripes or spots) that are unique to each individual. Cougars, however, are uniformly pelaged, and photo identification must be based on subtler attributes such as scars, ear nicks or body morphology. There is some debate as to whether these types of features are sufficient for photo-CMR, but there is little research directly evaluating its feasibility with cougars. Aim We aimed to examine researchers’ ability to reliably identify individual cougars in photographs taken from a camera-trapping survey, in order to evaluate the appropriateness of photo-CMR for estimating cougar abundance or CMR-derived parameters. Methods We collected cougar photo detections using a grid of 55 remote camera traps in north-west Wyoming, USA. The photo detections were distributed to professional biologists working in cougar research, who independently attempted to identify individuals in a pairwise matching process. We assessed the level to which their results agreed, using simple percentage agreement and Fleiss’s kappa. We also generated and compared spatially explicit capture–recapture (SECR) density estimates using their resultant detection histories. Key results There were no cases where participants were in full agreement on a cougar’s ID. Agreement in photo identification among participants was low (n = 7; simple agreement = 46.7%; Fleiss’s kappa = 0.183). The resultant SECR density estimates ranged from 0.7 to 13.5 cougars per 100 km2 (n = 4; s.d. = 6.11). Conclusion We were unable to produce reliable estimates of cougar density using photo-CMR, due to our inability to accurately photo-tag detected individuals. Abundance estimators that do not require complete photo-tagging (i.e. mark–resight) were also infeasible, given the lack of agreement on any single cougar’s ID. Implications This research suggested that there are substantial problems with the application of photo-CMR to estimate the size of cougar populations. Although improvements in camera technology or field methods may resolve these issues, researchers attempting to use this method on cougars should be cautious.

scholarly journals Density trends of wild felids in northern Laos

2021 ◽  
Author(s):  
Akchousanh Rasphone ◽  
Jan F. Kamler ◽  
Mathias Tobler ◽  
David W. Macdonald
Keyword(s):  
National Park ◽  
Community Outreach ◽  
Camera Trap ◽  
Panthera Tigris ◽  
Mesopredator Release ◽  
Density Estimates ◽  
Clouded Leopard ◽  
Capture Recapture ◽  
Leopard Cat ◽  
Prionailurus Bengalensis

AbstractDetermining the density trends of a guild of species can help illuminate their interactions, and the impacts that humans might have on them. We estimated the density trends from 2013 to 2017 of the clouded leopard Neofelis nebulosa, leopard cat Prionailurus bengalensis and marbled cat Pardofelis marmorata in Nam Et—Phou Louey National Park (NEPL), Laos, using camera trap data and spatial capture-recapture models. Mean (± SD) density estimates (individuals/100 km2) for all years were 1.77 ± 0.30 for clouded leopard, 1.50 ± 0.30 for leopard cat, and 3.80 ± 0.70 for marbled cat. There was a declining trend in density across the study years for all three species, with a ≥ 90% probability of decline for clouded leopard and leopard cat and an 83% probability of decline for marbled cat. There was no evidence that mesopredator release occurred as a result of tiger (Panthera tigris) and leopard (P. pardus) extirpations. We believe that snaring, the factor that led to the extirpation of tiger and leopard in NEPL, is now contributing to the decline of smaller felids, to an extent that over-rides any potential effects of mesopredator release on their densities and interactions. We recommend that the NEPL managers implement a more systematic and intensified snare removal program, in concert with extensive community outreach and engagement of local people to prevent the setting of snares. These actions might be the only hope for saving the remaining members of the felid community in NEPL.

scholarly journals Factors affecting the occurrence and activity of clouded leopards, common leopards and leopard cats in the Himalayas

2019 ◽  
Vol 29 (3) ◽  
pp. 839-851 ◽  
Author(s):  
Özgün Emre Can ◽  
Bhupendra Prasad Yadav ◽  
Paul J. Johnson ◽  
Joanna Ross ◽  
Neil D’Cruze ◽  
...  
Keyword(s):  
National Park ◽  
Prey Species ◽  
Camera Traps ◽  
Musk Deer ◽  
Clouded Leopard ◽  
Factors Affecting ◽  
The North ◽  
Hard Evidence ◽  
The Common ◽  
First Time

AbstractClouded leopards are one of the least known of larger felids and were believed to be extinct in Nepal until 1987. They are particularly interesting because their Asian range spans a diversity of habitats in the fastest disappearing forests in the world and encompasses a guild which differs in composition from place to place. As a part of a wider camera-trapping study of this guild, involving 2948 camera traps at 45 sites in nine countries, and paralleling a similar study of the Sunda clouded leopard including a further 1544 camera traps spanning 22 sites distributed across two countries, we deployed 84 pairs of camera traps for 107 days in 2014 and 2015 at Langtang National Park, Nepal between 1823 and 3824 m a.s.l. within a grid encompassing c. 120 km2. We documented the presence of clouded leopards for the first time at an altitude as high as 3498 m a.s.l. Naïve occupancy for clouded leopard was 8.6% (correcting for detection, 10.1%). Clouded leopards were least active in the middle of the day, and largely crepuscular and nocturnal, as were the common leopards and leopard cats. The peak of clouded leopard activity overlapped with that of musk deer. Prey species for both clouded leopard and common leopard were available across the elevation range studied although the availability of some prey species declined as elevation increased, whereas Himalayan serow, Himalayan goral, and musk deer showed no association with elevation. Before this study, there was no hard evidence that clouded leopards occurred above 2300 m a.s.l., having documented them at almost 4000 m a.s.l. in the Himalayas, we emphasise the importance of this extreme portion of the species’ range where climate is likely to change more rapidly and with greater consequences, than the global average. The discovery of clouded leopards in Langtang National Park considerably extends their known range, and raises the possibility that they occur from the Terai in southern Nepal up to the Nepal-Tibet (China) border in the north. Insofar as this study has extended the known extreme boundary of the clouded leopard’s geographic range to encompass Langtang National Park in the Nepali Himalayas.

scholarly journals Sunda clouded leopard Neofelis diardi densities and human activities in the humid evergreen rainforests of Sumatra

Oryx ◽  
2020 ◽  
pp. 1-8
Author(s):  
Iding Haidir ◽  
David W. Macdonald ◽  
Matthew Linkie
Keyword(s):  
Conservation Planning ◽  
Forest Edge ◽  
Camera Trap ◽  
Camera Traps ◽  
Spatially Explicit ◽  
Clouded Leopard ◽  
Wild Felids ◽  
The Status ◽  
In The Wild ◽  
Capture Recapture

Abstract Most species of wild felids are threatened, but for many little is known about their status in the wild. For the cryptic and elusive Vulnerable Sunda clouded leopard Neofelis diardi, key metrics such as abundance and occupancy have been challenging to obtain. We conducted an intensive survey for this species on the Indonesian island of Sumatra. We deployed camera traps across four study areas that varied in elevation and threats, for a total of 28,404 trap nights, resulting in 114 independent clouded leopard photographs, in which we identified 18 individuals. Using a Bayesian spatially explicit capture–recapture analysis, we estimated clouded leopard density to be 0.8–2.4 individuals/100 km2. The highest predicted occurrence of people was at lower altitudes and closer to the forest edge, where we categorized more than two-thirds of people recorded by camera traps as bird poachers, 12.5% each as ungulate/tiger poachers and non-timber collectors, and < 2% as fishers. Our findings provide important insights into the status of this little known species in Sumatra. We recommend that the large volume of camera-trap data from other Sumatran landscapes be used for an island-wide assessment of the clouded leopard population, to provide up-to-date and reliable information for guiding future conservation planning.

scholarly journals Spatially Explicit Capture-Recapture Through Camera Trapping: A Review of Benchmark Analyses for Wildlife Density Estimation

2020 ◽  
Vol 8 ◽  
Author(s):  
Austin M. Green ◽  
Mark W. Chynoweth ◽  
Çağan Hakkı Şekercioğlu
Keyword(s):  
Density Estimation ◽  
Study Design ◽  
New Technologies ◽  
Model Development ◽  
Population Monitoring ◽  
Camera Traps ◽  
Camera Trapping ◽  
Individual Identification ◽  
Spatially Explicit ◽  
Capture Recapture

Camera traps have become an important research tool for both conservation biologists and wildlife managers. Recent advances in spatially explicit capture-recapture (SECR) methods have increasingly put camera traps at the forefront of population monitoring programs. These methods allow for benchmark analysis of species density without the need for invasive fieldwork techniques. We conducted a review of SECR studies using camera traps to summarize the current focus of these investigations, as well as provide recommendations for future studies and identify areas in need of future investigation. Our analysis shows a strong bias in species preference, with a large proportion of studies focusing on large felids, many of which provide the only baseline estimates of population density for these species. Furthermore, we found that a majority of studies produced density estimates that may not be precise enough for long-term population monitoring. We recommend simulation and power analysis be conducted before initiating any particular study design and provide examples using readily available software. Furthermore, we show that precision can be increased by including a larger study area that will subsequently increase the number of individuals photo-captured. As many current studies lack the resources or manpower to accomplish such an increase in effort, we recommend that researchers incorporate new technologies such as machine-learning, web-based data entry, and online deployment management into their study design. We also cautiously recommend the potential of citizen science to help address these study design concerns. In addition, modifications in SECR model development to include species that have only a subset of individuals available for individual identification (often called mark-resight models), can extend the process of explicit density estimation through camera trapping to species not individually identifiable.

scholarly journals Leopard Density Estimation within an Enclosed Reserve, Namibia Using Spatially Explicit Capture-Recapture Models

Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 724
Author(s):  
Noack ◽  
Heyns ◽  
Rodenwoldt ◽  
Edwards
Keyword(s):  
Management Strategies ◽  
Camera Traps ◽  
Spatially Explicit ◽  
Conservation Areas ◽  
Term Survival ◽  
New Class ◽  
Capture Recapture ◽  
Wildlife Populations ◽  
Effective Conservation

The establishment of enclosed conservation areas are claimed to be the driving force for the long-term survival of wildlife populations. Whilst fencing provides an important tool in conservation, it simultaneously represents a controversial matter as it stops natural migration processes, which could ultimately lead to inbreeding, a decline in genetic diversity and local extinction if not managed correctly. Thus, wildlife residing in enclosed reserves requires effective conservation and management strategies, which are strongly reliant on robust population estimates. Here, we used camera traps combined with the relatively new class of spatially explicit capture-recaptured models (SECR) to produce the first reliable leopard population estimate for an enclosed reserve in Namibia. Leopard density was estimated at 14.51 leopards/100 km2, the highest recorded density in Namibia to date. A combination of high prey abundance, the absence of human persecution and a lack of top-down control are believed to be the main drivers of the recorded high leopard population. Our results add to the growing body of literature which suggests enclosed reserves have the potential to harbour high densities and highlight the importance of such reserves for the survival of threatened species in the future.

scholarly journals First photographic evidence of Fishing Cat Prionailurus viverrinus Bennett, 1833 and Clouded Leopard Neofelis nebulosa Griffith, 1821 (Carnivora: Felidae) in Parsa National Park, Nepal

2019 ◽  
Vol 11 (4) ◽  
pp. 13497-13501 ◽  
Author(s):  
Shashank Poudel ◽  
Babu Ram Lamichhane ◽  
Santosh Bhattarai ◽  
Dipendra Adhikari ◽  
Chiranjibi Prasad Pokheral ◽  
...  
Keyword(s):  
National Park ◽  
Conservation Status ◽  
Panthera Tigris ◽  
Clouded Leopard ◽  
Central Nepal ◽  
Photographic Evidence ◽  
Neofelis Nebulosa ◽  
Southern Central ◽  
Distribution And Ecology ◽  
Wild Cats

Twelve cat species were recorded in Nepal including the largest, Tiger Panthera tigris, and the smallest, Rusty-spotted Cat Prionailurus rubiginosus.  There is more research on the Panthera species than on small wild cats; consequently, the conservation status, distribution, and ecology of small cat species are poorly known.  In this article, we report on the first photographic evidence of Clouded Leopard Neofelis nebulosa and Fishing Cat Prionailurus viverrinus in Parsa National Park in southern central Nepal during a camera trap survey targeted at the tiger between 2014 and 2016.  There were only single detections of each species; this does not give enough information to establish distribution or conservation status of either of the species in Parsa National Park.  Further targeted surveys are needed to establish the significance of this protected area for the conservation of these two species.

scholarly journals Density Estimates of Unmarked Large Mammals at Camera Traps Vary among Models, Species, and Years, Signalling Importance of Model Assumptions

2021 ◽  
Author(s):  
Jason Fisher ◽  
Joanna Burgar ◽  
Melanie Dickie ◽  
Cole Burton ◽  
Rob Serrouya
Keyword(s):  
Density Estimation ◽  
Black Bear ◽  
Camera Traps ◽  
Mammal Species ◽  
Density Estimates ◽  
Movement Rates ◽  
Social Species ◽  
Marked Variability ◽  
Capture Recapture ◽  
Best Fitting

Density estimation is a key goal in ecology but accurate estimates remain elusive, especially for unmarked animals. Data from camera-trap networks combined with new density estimation models can bridge this gap but recent research has shown marked variability in accuracy, precision, and concordance among estimators. We extend this work by comparing estimates from two different classes of models: unmarked spatial capture-recapture (spatial count, SC) models, and Time In Front of Camera (TIFC) models, a class of random encounter model. We estimated density for four large mammal species with different movement rates, behaviours, and sociality, as these traits directly relate to model assumptions. TIFC density estimates were typically higher than SC model estimates for all species. Black bear TIFC estimates were ~ 10-fold greater than SC estimates. Caribou TIFC estimates were 2-10 fold greater than SC estimates. White-tailed deer TIFC estimates were up to 100-fold greater than SC estimates. Differences of 2-5 fold were common for other species in other years. SC estimates were annually stable except for one social species; TIFC estimates were highly annually variable in some cases and consistent in others. Tests against densities obtained from DNA surveys and aerial surveys also showed variable concordance and divergence. For gregarious animals TIFC may outperform SC due to the latter model’s assumption of independent activity centres. For curious animals likely to investigate camera traps, SC may outperform TIFC, which assumes animal behavior is unaffected by cameras. Unmarked models offer great possibilities, but a pragmatic approach employs multiple estimators where possible, considers the ecological plausibility of assumptions, and uses an informed multi-inference approach to seek estimates from models with assumptions best fitting a species’ biology.

Spatially explicit capture-recapture method (SECR, SPACECAP): A new approach to determination of the Amur tiger (Panthera tigris altaica) population density by means of camera-traps

2013 ◽  
Vol 453 (1) ◽  
pp. 365-368 ◽  
Author(s):  
J. A. Hernandez-Blanco ◽  
V. V. Rozhnov ◽  
V. S. Lukarevskiy ◽  
S. V. Naidenko ◽  
M. D. Chistopolova ◽  
...  
Keyword(s):  
Population Density ◽  
Camera Traps ◽  
Spatially Explicit ◽  
Panthera Tigris ◽  
Amur Tiger ◽  
New Approach ◽  
Panthera Tigris Altaica ◽  
Capture Recapture
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