Methodological approaches for estimating populations of the endangered dhole Cuon alpinus
Large carnivores are important for maintaining ecosystem integrity and attract much research and conservation interest. For most carnivore species, estimating population density or abundance is challenging because they do not have unique markings for individual identification. This hinders status as...
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PeerJ Inc.
2022-02-01
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| author | Girish A. Punjabi Linnea Worsøe Havmøller Rasmus Worsøe Havmøller Dusit Ngoprasert Arjun Srivathsa |
| author_facet | Girish A. Punjabi Linnea Worsøe Havmøller Rasmus Worsøe Havmøller Dusit Ngoprasert Arjun Srivathsa |
| author_sort | Girish A. Punjabi |
| collection | DOAJ |
| description | Large carnivores are important for maintaining ecosystem integrity and attract much research and conservation interest. For most carnivore species, estimating population density or abundance is challenging because they do not have unique markings for individual identification. This hinders status assessments for many threatened species, and calls for testing new methodological approaches. We examined past efforts to assess the population status of the endangered dhole (Cuon alpinus), and explored the application of a suite of recently developed models for estimating their populations using camera-trap data from India’s Western Ghats. We compared the performance of Site-Based Abundance (SBA), Space-to-Event (STE), and Time-to-Event (TTE) models against current knowledge of their population size in the area. We also applied two of these models (TTE and STE) to the co-occurring leopard (Panthera pardus), for which density estimates were available from Spatially Explicit Capture–Recapture (SECR) models, so as to simultaneously validate the accuracy of estimates for one marked and one unmarked species. Our review of literature (n = 38) showed that most assessments of dhole populations involved crude indices (relative abundance index; RAI) or estimates of occupancy and area of suitable habitat; very few studies attempted to estimate populations. Based on empirical data from our field surveys, the TTE and SBA models overestimated dhole population size beyond ecologically plausible limits, but the STE model produced reliable estimates for both the species. Our findings suggest that it is difficult to estimate population sizes of unmarked species when model assumptions are not fully met and data are sparse, which are commonplace for most ecological surveys in the tropics. Based on our assessment, we propose that practitioners who have access to photo-encounter data on dholes across Asia test old and new analytical approaches to increase the overall knowledge-base on the species, and contribute towards conservation monitoring of this endangered carnivore. |
| first_indexed | 2024-03-09T07:54:02Z |
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| id | doaj.art-e02de8b135e848f39cda9846d781d061 |
| institution | Directory Open Access Journal |
| issn | 2167-8359 |
| language | English |
| last_indexed | 2024-03-09T07:54:02Z |
| publishDate | 2022-02-01 |
| publisher | PeerJ Inc. |
| record_format | Article |
| series | PeerJ |
| spelling | doaj.art-e02de8b135e848f39cda9846d781d0612023-12-03T01:21:15ZengPeerJ Inc.PeerJ2167-83592022-02-0110e1290510.7717/peerj.12905Methodological approaches for estimating populations of the endangered dhole Cuon alpinusGirish A. Punjabi0Linnea Worsøe Havmøller1Rasmus Worsøe Havmøller2Dusit Ngoprasert3Arjun Srivathsa4Dhole Working Group, IUCN/SCC Canid Specialist Group, The Recanati Kaplan Centre, Tubney House, Tubney, United KingdomDhole Working Group, IUCN/SCC Canid Specialist Group, The Recanati Kaplan Centre, Tubney House, Tubney, United KingdomResearch and Collections, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, DenmarkConservation Ecology Program, King Mongkut’s University of Technology Thonburi, Bangkok, ThailandDhole Working Group, IUCN/SCC Canid Specialist Group, The Recanati Kaplan Centre, Tubney House, Tubney, United KingdomLarge carnivores are important for maintaining ecosystem integrity and attract much research and conservation interest. For most carnivore species, estimating population density or abundance is challenging because they do not have unique markings for individual identification. This hinders status assessments for many threatened species, and calls for testing new methodological approaches. We examined past efforts to assess the population status of the endangered dhole (Cuon alpinus), and explored the application of a suite of recently developed models for estimating their populations using camera-trap data from India’s Western Ghats. We compared the performance of Site-Based Abundance (SBA), Space-to-Event (STE), and Time-to-Event (TTE) models against current knowledge of their population size in the area. We also applied two of these models (TTE and STE) to the co-occurring leopard (Panthera pardus), for which density estimates were available from Spatially Explicit Capture–Recapture (SECR) models, so as to simultaneously validate the accuracy of estimates for one marked and one unmarked species. Our review of literature (n = 38) showed that most assessments of dhole populations involved crude indices (relative abundance index; RAI) or estimates of occupancy and area of suitable habitat; very few studies attempted to estimate populations. Based on empirical data from our field surveys, the TTE and SBA models overestimated dhole population size beyond ecologically plausible limits, but the STE model produced reliable estimates for both the species. Our findings suggest that it is difficult to estimate population sizes of unmarked species when model assumptions are not fully met and data are sparse, which are commonplace for most ecological surveys in the tropics. Based on our assessment, we propose that practitioners who have access to photo-encounter data on dholes across Asia test old and new analytical approaches to increase the overall knowledge-base on the species, and contribute towards conservation monitoring of this endangered carnivore.https://peerj.com/articles/12905.pdfCamera trappingCanidsConservation monitoringModel evaluationSite-based abundanceSpace-to-event |
| spellingShingle | Girish A. Punjabi Linnea Worsøe Havmøller Rasmus Worsøe Havmøller Dusit Ngoprasert Arjun Srivathsa Methodological approaches for estimating populations of the endangered dhole Cuon alpinus PeerJ Camera trapping Canids Conservation monitoring Model evaluation Site-based abundance Space-to-event |
| title | Methodological approaches for estimating populations of the endangered dhole Cuon alpinus |
| title_full | Methodological approaches for estimating populations of the endangered dhole Cuon alpinus |
| title_fullStr | Methodological approaches for estimating populations of the endangered dhole Cuon alpinus |
| title_full_unstemmed | Methodological approaches for estimating populations of the endangered dhole Cuon alpinus |
| title_short | Methodological approaches for estimating populations of the endangered dhole Cuon alpinus |
| title_sort | methodological approaches for estimating populations of the endangered dhole cuon alpinus |
| topic | Camera trapping Canids Conservation monitoring Model evaluation Site-based abundance Space-to-event |
| url | https://peerj.com/articles/12905.pdf |
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