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Honiball T, Davis RS, Ntlokwana L, Venter JA. Lion lords and sharing hyaenas: Carnivore guild dynamics around elephant carcasses. Ecol Evol 2024; 14:e11373. [PMID: 38711489 PMCID: PMC11070635 DOI: 10.1002/ece3.11373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 04/11/2024] [Accepted: 04/18/2024] [Indexed: 05/08/2024] Open
Abstract
Megaherbivore carcasses represent sporadic but energetically rewarding resources for carnivores, offering a unique opportunity to study coexistence dynamics between facultative scavengers. South African fenced protected areas, such as Madikwe Game Reserve (Madikwe hereafter), host viable populations of large carnivores and high densities of elephants, Loxodonta africana. However, high carnivore densities can lead to potentially fatal interspecific encounters and increased competition, particularly around high-quality trophic resources. This study explores the temporal partitioning and co-detection strategies of carnivores at six elephant carcasses in Madikwe, aiming to understand how the increased carrion biomass available at elephant carcasses influences coexistence dynamics. Camera traps were deployed to monitor carcasses during two periods (2019 and 2020), revealing occurrences of six carnivore species. Carnivores, particularly black-backed jackals, Lupulella mesomelas, (hereafter jackal), lions, Panthera leo, and spotted hyaenas, Crocuta crocuta, comprised 56.7% of carcass observations, highlighting their pivotal roles in scavenging dynamics. Pairwise co-detection analysis demonstrated consistent association and shared peak activity periods between jackals and spotted hyaenas, indicating potential resource sharing. However, the minimal co-detection rates between lions and other carnivores highlight their resource domination. There was some evidence of temporal partitioning between carnivores, with most species exhibiting earlier peaks in nocturnal activity to avoid temporal overlap with lions. This study emphasises the importance of elephant carcasses in the diet of multiple species and coexistence techniques utilised to exploit this ephemeral resource. As fenced protected areas become crucial for conserving intact carnivore guilds globally, further research into carnivore behavioural adaptations at carcasses is recommended to shed light on their coexistence strategies.
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Affiliation(s)
- Terry‐Lee Honiball
- Department of Conservation Management, Natural Resource Science and Management Cluster, Faculty of ScienceNelson Mandela UniversityGeorgeSouth Africa
| | - Robert S. Davis
- Department of Conservation Management, Natural Resource Science and Management Cluster, Faculty of ScienceNelson Mandela UniversityGeorgeSouth Africa
| | - Liyabona Ntlokwana
- Department of Conservation Management, Natural Resource Science and Management Cluster, Faculty of ScienceNelson Mandela UniversityGeorgeSouth Africa
| | - Jan A. Venter
- Department of Conservation Management, Natural Resource Science and Management Cluster, Faculty of ScienceNelson Mandela UniversityGeorgeSouth Africa
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Srivathsa A, Ramachandran V, Saravanan P, Sureshbabu A, Ganguly D, Ramakrishnan U. Topcats and underdogs: intraguild interactions among three apex carnivores across Asia's forestscapes. Biol Rev Camb Philos Soc 2023; 98:2114-2135. [PMID: 37449566 DOI: 10.1111/brv.12998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 06/26/2023] [Accepted: 07/04/2023] [Indexed: 07/18/2023]
Abstract
Intraguild interactions among carnivores have long held the fascination of ecologists. Ranging from competition to facilitation and coexistence, these interactions and their complex interplay influence everything from species persistence to ecosystem functioning. Yet, the patterns and pathways of such interactions are far from understood in tropical forest systems, particularly across countries in the Global South. Here, we examined the determinants and consequences of competitive interactions between dholes Cuon alpinus and the two large felids (leopards Panthera pardus and tigers Panthera tigris) with which they most commonly co-occur across Asia. Using a combination of traditional and novel data sources (N = 118), we integrate information from spatial, temporal, and dietary niche dimensions. These three species have faced catastrophic declines in their extent of co-occurrence over the past century; most of their source populations are now confined to Protected Areas. Analysis of dyadic interactions between species pairs showed a clear social hierarchy. Tigers were dominant over dholes, although pack strength in dholes helped ameliorate some of these effects; leopards were subordinate to dholes. Population-level spatio-temporal interactions assessed at 25 locations across Asia did not show a clear pattern of overlap or avoidance between species pairs. Diet-profile assessments indicated that wild ungulate biomass consumption by tigers was highest, while leopards consumed more primate and livestock prey as compared to their co-predators. In terms of prey offtake (ratio of wild prey biomass consumed to biomass available), the three species together harvested 0.4-30.2% of available prey, with the highest offtake recorded from the location where the carnivores reach very high densities. When re-examined in the context of prey availability and offtake, locations with low wild prey availability showed spatial avoidance and temporal overlap among the carnivore pairs, and locations with high wild prey availability showed spatial overlap and temporal segregation. Based on these observations, we make predictions for 40 Protected Areas in India where temporally synchronous estimates of predator and prey densities are available. We expect that low prey availability will lead to higher competition, and in extreme cases, to the complete exclusion of one or more species. In Protected Areas with high prey availability, we expect intraguild coexistence and conspecific competition among carnivores, with spill-over to forest-edge habitats and subsequent prey-switching to livestock. We stress that dhole-leopard-tiger co-occurrence across their range is facilitated through an intricate yet fragile balance between prey availability, and intraguild and conspecific competition. Data gaps and limitations notwithstanding, our study shows how insights from fundamental ecology can be of immense utility for applied aspects like large predator conservation and management of human-carnivore interactions. Our findings also highlight potential avenues for future research on tropical carnivores that can broaden current understanding of intraguild competition in forest systems of Asia and beyond.
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Affiliation(s)
- Arjun Srivathsa
- National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
- Wildlife Conservation Society-India, 551, 7th Main Road, 2nd Stage Rajiv Gandhi Nagar, Kodigehalli, Bengaluru, 560097, India
| | - Vivek Ramachandran
- National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
- Wildlife Biology and Conservation Program, National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
| | - Pooja Saravanan
- National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
| | - Abhijith Sureshbabu
- National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
| | - Divyajyoti Ganguly
- National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
- Wildlife Biology and Conservation Program, National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
| | - Uma Ramakrishnan
- National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Bengaluru, 560065, India
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Malla R, Panthi S, Adhikari H, Pariyar S, Baral R, Subedi R, Adhikari BP, Poudel M, Sedhai N, Poudel M. Habitat suitability of four threatened Himalayan species: Asiatic black bear, common leopard, musk deer, and snow leopard. PeerJ 2023; 11:e16085. [PMID: 37780372 PMCID: PMC10538300 DOI: 10.7717/peerj.16085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 08/21/2023] [Indexed: 10/03/2023] Open
Abstract
Background Biodiversity conservation is becoming challenging day by day. For this, it is essential to understand the distribution, habitat, and impact of anthropogenic activities on animals at risk. We assessed the suitable habitats and anthropogenic impacts on Asiatic black bears, common leopards, musk deer, and snow leopards in and outside the protected areas of Gandaki Province, Nepal. Methods We collected the presence locations of Asiatic black bears, common leopards, musk deer, and snow leopards based on scats and other signs. We employed the Maximum Entropy (MaxEnt) tool to identify suitable habitats of our studied species and their anthropogenic impacts on them. Results The total suitable habitat of the common leopard was found to be 6,052 km2, followed by the Asiatic black bear (5,819 km2), snow leopard (4,447 km2), and musk deer (1,690 km2) in Gandaki Province. Most of the areas of suitable habitat for common leopards and Asiatic black bears were outside the protected areas, and for musk deer and snow leopards were inside the protected areas. Elevation was the most important variable determining habitat suitability of Asiatic black bear, common leopard, and musk deer, whereas the distance to water was the most important variable determining habitat suitability of snow leopard. Asiatic black bears, common leopards, and musk deer face significant anthropogenic impacts, but snow leopards face some anthropogenic impacts. Conclusion Managing these animals' habitats inside and outside protected areas is essential. Hence, biodiversity conservation and livelihood opportunities should be balanced in the Himalayas on a win-win basis.
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Affiliation(s)
- Rajesh Malla
- Forest Research and Training Center, Pokhara, Nepal
| | - Saroj Panthi
- Ministry of Industry, Tourism, Forests and Environment, Gandaki Province, Pokhara, Nepal
| | - Hari Adhikari
- Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland
| | - Shiva Pariyar
- Ministry of Industry, Tourism, Forests and Environment, Gandaki Province, Pokhara, Nepal
| | - Rishi Baral
- National Trust for Nature Conservation, Annapurna Conservation Area, Pokhara, Nepal
| | | | | | | | | | - Megharaj Poudel
- Division Forest Office, Nawalpur, Nawalparsi (Bardaghat Susta East), Kawasoti, Nepal
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Greenspan E, Montgomery C, Stokes D, K'lu SS, Moo SSB, Anile S, Giordano AJ, Nielsen CK. Occupancy, density, and activity patterns of a Critically Endangered leopard population on the
Kawthoolei‐Thailand
border. POPUL ECOL 2023. [DOI: 10.1002/1438-390x.12148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Evan Greenspan
- Karen Wildlife Conservation Initiative Willagee Western Australia Australia
| | - Clara Montgomery
- Karen Wildlife Conservation Initiative Willagee Western Australia Australia
| | - Demelza Stokes
- Karen Wildlife Conservation Initiative Willagee Western Australia Australia
| | - Saw Say K'lu
- Kawthoolei Forestry Department Chiang Mai Thailand
| | | | - Stefano Anile
- Forestry Program and Cooperative Wildlife Research Laboratory Southern Illinois University Carbondale Illinois USA
| | | | - Clayton K. Nielsen
- Forestry Program and Cooperative Wildlife Research Laboratory Southern Illinois University Carbondale Illinois USA
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Morin DJ, Lesmeister DB, Nielsen CK, Schauber EM. Asymmetrical intraguild interactions with coyotes, red foxes, and domestic dogs may contribute to competitive exclusion of declining gray foxes. Ecol Evol 2022; 12:e9074. [PMID: 35813925 PMCID: PMC9251843 DOI: 10.1002/ece3.9074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/05/2022] [Accepted: 06/08/2022] [Indexed: 11/07/2022] Open
Abstract
Species coexistence is governed by availability of resources and intraguild interactions including strategies to reduce ecological overlap. Gray foxes are dietary generalist mesopredators expected to benefit from anthropogenic disturbance, but populations have declined across the midwestern USA, including severe local extirpation rates coinciding with high coyote and domestic dog occurrence and low red fox occurrence. We used data from a large‐scale camera trap survey in southern Illinois, USA to quantify intraguild spatial and temporal interactions among the canid guild including domestic dogs. We used a two‐species co‐occurrence model to make pairwise assessments of conditional occupancy and detection rates. We also estimated temporal activity overlap among species and fit a fixed‐effects hierarchical community occupancy model with the four canid species. We partitioned the posterior distributions to compare gray fox occupancy probabilities conditional on estimated state of combinations of other species to assess support for hypothesized interactions. We found no evidence of broadscale avoidance among native canids and conclude that spatial and temporal segregation were limited by ubiquitous human disturbance. Mean guild richness was two canid species at a site and gray fox occupancy was greater when any combination of sympatric canids was also present, setting the stage for competitive exclusion over time. Domestic dogs may amplify competitive interactions by increasing canid guild size to the detriment of gray foxes. Our results suggest that while human activities can benefit some mesopredators, other species such as gray foxes may serve as bellwethers for habitat degradation with trophic downgrading and continued anthropogenic homogenization.
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Affiliation(s)
- Dana J. Morin
- Department of Wildlife, Fisheries and Aquaculture Mississippi State University Mississippi State Mississippi USA
| | - Damon B. Lesmeister
- Pacific Northwest Research Station, U.S. Forest Service and Department of Fisheries and Wildlife Oregon State University Corvallis Oregon USA
| | - Clayton K. Nielsen
- Cooperative Wildlife Research Laboratory and Forestry Program Southern Illinois University Carbondale Illinois USA
| | - Eric M. Schauber
- Illinois Natural History Survey, Prairie Research Institute University of Illinois Urbana‐Champaign Champaign Illinois USA
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Paudel RP, Kadariya R, Lamichhane BR, Subedi N, Sashika M, Shimozuru M, Tsubota T. Habitat occupancy of sloth bear Melursus ursinus in Chitwan National Park, Nepal. Ecol Evol 2022; 12:e8699. [PMID: 35342572 PMCID: PMC8928908 DOI: 10.1002/ece3.8699] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 11/08/2022] Open
Abstract
Mammals have experienced a massive decline in their populations and geographic ranges worldwide. The sloth bear, Melursus ursinus (Shaw, 1791), is one of many species facing conservation threats. Despite being endangered in Nepal, decades of inattention to the situation have hindered their conservation and management. We assessed the distribution and patterns of habitat use by sloth bears in Chitwan National Park (CNP), Nepal. We conducted sign surveys from March to June, 2020, in 4 × 4 km grids (n = 45). We collected detection/non-detection data along a 4-km trail that was divided into 20 continuous segments of 200 m each. We obtained environmental, ecological, and anthropogenic covariates to understand determinants of sloth bear habitat occupancy. The data were analyzed using the single-species single-season occupancy method, with a spatially correlated detection. Using repeated observations, these models accounted for the imperfect detectability of the species to provide robust estimates of habitat occupancy. The model-averaged occupancy estimate for the sloth bear was 69% and the detection probability was 0.25. The probability of habitat occupancy by sloth bears increased with the presence of termites and fruits and in rugged, dry, open, undisturbed habitats. Our results indicate that the sloth bear is elusive, functionally unique, and widespread in CNP. Future conservation interventions and action plans aimed at sloth bear management must adequately consider their habitat requirements.
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Affiliation(s)
- Rajan Prasad Paudel
- Laboratory of Wildlife Biology and MedicineDepartment of Environmental Veterinary ScienceGraduate School of Veterinary MedicineHokkaido UniversitySapporoJapan
| | | | | | | | - Mariko Sashika
- Laboratory of Wildlife Biology and MedicineDepartment of Environmental Veterinary ScienceGraduate School of Veterinary MedicineHokkaido UniversitySapporoJapan
| | - Michito Shimozuru
- Laboratory of Wildlife Biology and MedicineDepartment of Environmental Veterinary ScienceGraduate School of Veterinary MedicineHokkaido UniversitySapporoJapan
| | - Toshio Tsubota
- Laboratory of Wildlife Biology and MedicineDepartment of Environmental Veterinary ScienceGraduate School of Veterinary MedicineHokkaido UniversitySapporoJapan
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Pokharel M, Subba A, Rai D, Bhandari S, Ghimirey Y. Fine-scale ecological and anthropogenic variables predict the habitat use and detectability of sloth bears in the Churia habitat of east Nepal. Ecol Evol 2022; 12:e8512. [PMID: 35136560 PMCID: PMC8809446 DOI: 10.1002/ece3.8512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 12/09/2021] [Accepted: 12/14/2021] [Indexed: 11/30/2022] Open
Abstract
Once widespread throughout the tropical forests of the Indian Subcontinent, the sloth bears have suffered a rapid range collapse and local extirpations in the recent decades. A significant portion of their current distribution range is situated outside of the protected areas (PAs). These unprotected sloth bear populations are under tremendous human pressures, but little is known about the patterns and determinants of their occurrence in most of these regions. The situation is more prevalent in Nepal where virtually no systematic information is available for sloth bears living outside of the PAs. We undertook a spatially replicated sign survey-based single-season occupancy study intending to overcome this information gap for the sloth bear populations residing in the Trijuga forest of southeast Nepal. Sloth bear sign detection histories and field-based covariates data were collected between 2 October and 3 December 2020 at the 74 randomly chosen 4-km2 grid cells. From our results, the model-averaged site use probability (ψ ± SE) was estimated to be 0.432 ± 0.039, which is a 13% increase from the naïve estimate (0.297) not accounting for imperfect detections of sloth bear signs. The presence of termite mound and the distance to the nearest water source were the most important variables affecting the habitat use probability of sloth bears. The average site-level detectability (p ± SE) of sloth bear signs was estimated to be 0.195 ± 0.003 and was significantly determined by the index of human disturbances. We recommend considering the importance of fine-scale ecological and anthropogenic factors in predicting the sloth bear-habitat relationships across their range in the Churia habitat of Nepal, and more specifically in the unprotected areas.
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Affiliation(s)
- Manoj Pokharel
- Department of Environmental ScienceTri‐Chandra Multiple CampusKathmanduNepal
| | - Asmit Subba
- Central Department of ZoologyTribhuvan UniversityKathmanduNepal
| | - Dipa Rai
- Department of Environmental ScienceGoldenGate International CollegeKathmanduNepal
| | - Simrik Bhandari
- Department of Environmental Science and EngineeringKathmandu UniversityDhulikhelNepal
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Lamichhane BR, Lamichhane S, Regmi R, Dhungana M, Thapa SK, Prasai A, Gurung A, Bhattarai S, Paudel RP, Subedi N. Leopard ( Panthera pardus) occupancy in the Chure range of Nepal. Ecol Evol 2021; 11:13641-13660. [PMID: 34707806 PMCID: PMC8525094 DOI: 10.1002/ece3.8105] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 08/22/2021] [Accepted: 08/25/2021] [Indexed: 12/04/2022] Open
Abstract
Conservation of large carnivores such as leopards requires large and interconnected habitats. Despite the wide geographic range of the leopard globally, only 17% of their habitat is within protected areas. Leopards are widely distributed in Nepal, but their population status and occupancy are poorly understood. We carried out the sign-based leopard occupancy survey across the entire Chure range (~19,000 km2) to understand the habitat occupancy along with the covariates affecting their occupancy. Leopard signs were obtained from in 70 out of 223 grids surveyed, with a naïve leopard occupancy of 0.31. The model-averaged leopard occupancy was estimated to be 0.5732 (SE 0.0082) with a replication-level detection probability of 0.2554 (SE 0.1142). The top model shows the additive effect of wild boar, ruggedness, presence of livestock, and human population density positively affecting the leopard occupancy. The detection probability of leopard was higher outside the protected areas, less in the high NDVI (normalized difference vegetation index) areas, and higher in the areas with livestock presence. The presence of wild boar was strong predictor of leopard occupancy followed by the presence of livestock, ruggedness, and human population density. Leopard occupancy was higher in west Chure (0.70 ± SE 0.047) having five protected areas compared with east Chure (0.46 ± SE 0.043) with no protected areas. Protected areas and prey species had positive influence on leopard occupancy in west Chure range. Similarly in the east Chure, the leopard occupancy increased with prey, NDVI, and terrain ruggedness. Enhanced law enforcement and mass awareness activities are necessary to reduce poaching/killing of wild ungulates and leopards in the Chure range to increase leopard occupancy. In addition, maintaining the sufficient natural prey base can contribute to minimize the livestock depredation and hence decrease the human-leopard conflict in the Chure range.
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Affiliation(s)
| | | | - Rajan Regmi
- President ChureTerai Madhesh Conservation Development BoardLalitpurNepal
| | - Milan Dhungana
- President ChureTerai Madhesh Conservation Development BoardLalitpurNepal
| | | | - Anil Prasai
- National Trust for Nature ConservationLalitpurNepal
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