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Creel S, Reyes de Merkle J, Goodheart B, Mweetwa T, Mwape H, Simpamba T, Becker MS. An integrated population model reveals source-sink dynamics for competitively subordinate African wild dogs linked to anthropogenic prey depletion. J Anim Ecol 2024; 93:417-427. [PMID: 38311822 DOI: 10.1111/1365-2656.14052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 01/04/2024] [Indexed: 02/06/2024]
Abstract
Many African large carnivore populations are declining due to decline of the herbivore populations on which they depend. The densities of apex carnivores like the lion and spotted hyena correlate strongly with prey density, but competitively subordinate carnivores like the African wild dog benefit from competitive release when the density of apex carnivores is low, so the expected effect of a simultaneous decrease in resources and dominant competitors is not obvious. Wild dogs in Zambia's South Luangwa Valley Ecosystem occupy four ecologically similar areas with well-described differences in the densities of prey and dominant competitors due to spatial variation in illegal offtake. We used long-term monitoring data to fit a Bayesian integrated population model (IPM) of the demography and dynamics of wild dogs in these four regions. The IPM used Leslie projection to link a Cormack-Jolly-Seber model of area-specific survival (allowing for individual heterogeneity in detection), a zero-inflated Poisson model of area-specific fecundity and a state-space model of population size that used estimates from a closed mark-capture model as the counts from which (latent) population size was estimated. The IPM showed that both survival and reproduction were lowest in the region with the lowest density of preferred prey (puku, Kobus vardonii and impala, Aepyceros melampus), despite little use of this area by lions. Survival and reproduction were highest in the region with the highest prey density and intermediate in the two regions with intermediate prey density. The population growth rate (λ ) was positive for the population as a whole, strongly positive in the region with the highest prey density and strongly negative in the region with the lowest prey density. It has long been thought that the benefits of competitive release protect African wild dogs from the costs of low prey density. Our results show that the costs of prey depletion overwhelm the benefits of competitive release and cause local population decline where anthropogenic prey depletion is strong. Because competition is important in many guilds and humans are affecting resources of many types, it is likely that similarly fundamental shifts in population limitation are arising in many systems.
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Affiliation(s)
- Scott Creel
- Department of Ecology, Montana State University, Bozeman, Montana, USA
- Zambian Carnivore Programme, Mfuwe, Eastern Province, Zambia
| | - Johnathan Reyes de Merkle
- Department of Ecology, Montana State University, Bozeman, Montana, USA
- Zambian Carnivore Programme, Mfuwe, Eastern Province, Zambia
| | - Ben Goodheart
- Department of Ecology, Montana State University, Bozeman, Montana, USA
- Zambian Carnivore Programme, Mfuwe, Eastern Province, Zambia
| | | | - Henry Mwape
- Zambian Carnivore Programme, Mfuwe, Eastern Province, Zambia
| | - Twakundine Simpamba
- Department of National Parks and Wildlife, South Luangwa Area Management Unit, Mfuwe, Eastern Province, Zambia
| | - Matthew S Becker
- Department of Ecology, Montana State University, Bozeman, Montana, USA
- Zambian Carnivore Programme, Mfuwe, Eastern Province, Zambia
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Rafiq K, Jordan NR, Golabek K, McNutt JW, Wilson A, Abrahms B. Increasing ambient temperatures trigger shifts in activity patterns and temporal partitioning in a large carnivore guild. Proc Biol Sci 2023; 290:20231938. [PMID: 37935363 PMCID: PMC10645112 DOI: 10.1098/rspb.2023.1938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 10/09/2023] [Indexed: 11/09/2023] Open
Abstract
Shifts in species' interactions are implicated as an important proximate cause underpinning climate-change-related extinction. However, there is little empirical evidence on the pathways through which climate conditions, such as ambient temperature, impact community dynamics. The timing of activities is a widespread behavioural adaptation to environmental variability, and temporal partitioning is a key mechanism that facilitates coexistence, especially within large carnivore communities. We investigated temperature impacts on community dynamics through its influence on the diel activity of, and temporal partitioning amongst, four sympatric species of African large carnivores: lions (Panthera leo), leopards (Panthera pardus), cheetahs (Acinonyx jubatus) and African wild dogs (Lycaon pictus). Activity of all species was shaped by a combination of light availability and temperature, with most species becoming more nocturnal and decreasing activity levels with increasing temperatures. A nocturnal shift was most pronounced in cheetahs, the most diurnal species during median temperatures. This shift increased temporal overlap between cheetahs and other carnivore species by up to 15.92%, highlighting the importance of considering the responses of interacting sympatric species when inferring climate impacts on ecosystems. Our study provides evidence that temperature can significantly affect temporal partitioning within a carnivore guild by generating asymmetrical behavioural responses amongst functionally similar species.
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Affiliation(s)
- Kasim Rafiq
- Center for Ecosystem Sentinels, Department of Biology, University of Washington, Seattle 98195-0005, USA
- Botswana Predator Conservation, Maun, Botswana
| | - Neil R. Jordan
- Botswana Predator Conservation, Maun, Botswana
- Centre for Ecosystem Science, University of New South Wales, Sydney, Australia
- Taronga Conservation Society Australia, Sydney, Australia
| | - Krystyna Golabek
- Botswana Predator Conservation, Maun, Botswana
- Centre for Ecosystem Science, University of New South Wales, Sydney, Australia
| | | | - Alan Wilson
- Structure and Motion Lab, Royal Veterinary College, London, UK
| | - Briana Abrahms
- Center for Ecosystem Sentinels, Department of Biology, University of Washington, Seattle 98195-0005, USA
- Botswana Predator Conservation, Maun, Botswana
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Behr DM, Hodel FH, Cozzi G, McNutt JW, Ozgul A. Higher Mortality Is Not a Universal Cost of Dispersal: A Case Study in African Wild Dogs. Am Nat 2023; 202:616-629. [PMID: 37963118 DOI: 10.1086/726220] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
AbstractMortality is considered one of the main costs of dispersal. A reliable evaluation of mortality, however, is often hindered by a lack of information about the fate of individuals that disappear under unexplained circumstances (i.e., missing individuals). Here, we addressed this uncertainty by applying a Bayesian mortality analysis that inferred the fate of missing individuals according to information from individuals with known fate. Specifically, we tested the hypothesis that mortality during dispersal is higher than mortality among nondispersers using 32 years of mark-resighting data from a free-ranging population of the endangered African wild dog (Lycaon pictus) in northern Botswana. Contrary to expectations, we found that mortality during dispersal was lower than mortality among nondispersers, indicating that higher mortality is not a universal cost of dispersal. Our findings suggest that group living can incur costs for certain age classes, such as limited access to resources as group density increases, that exceed the mortality costs associated with dispersal. By challenging the accepted expectation of higher mortality during dispersal, we urge for further investigations of this key life history trait and propose a robust statistical approach to reduce bias in mortality estimates.
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Strampelli P, Henschel P, Searle CE, Macdonald DW, Dickman AJ. Spatial co-occurrence patterns of sympatric large carnivores in a multi-use African system. PLoS One 2023; 18:e0280420. [PMID: 36662874 PMCID: PMC9858824 DOI: 10.1371/journal.pone.0280420] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 01/02/2023] [Indexed: 01/21/2023] Open
Abstract
Interspecific interactions can be a key driver of habitat use, and must be accounted for in conservation planning. However, spatial partitioning between African carnivores, and how this varies with scale, remains poorly understood. Furthermore, most studies have taken place within small or highly protected areas, rather than in the heterogeneous, mixed-use landscapes characteristic of much of modern Africa. Here, we provide one of the first empirical investigations into population-level competitive interactions among an African large carnivore guild. We collected detection/non-detection data for an eastern African large carnivore guild in Tanzania's Ruaha-Rungwa conservation landscape, over an area of ~45,000 km2. We then applied conditional co-occupancy models to investigate co-occurrence between lion, leopard, and African wild dog, at two biologically meaningful scales. Co-occurrence patterns of cheetah and spotted hyaena could not be modelled. After accounting for habitat and detection effects, we found some evidence of wild dog avoidance of lion at the home range scale, and strong evidence of fine-scale avoidance. We found no evidence of interspecific exclusion of leopard by lion; rather, positive associations were observed at both scales, suggesting shared habitat preferences. We found little evidence of leopard habitat use being affected by wild dog. Our findings also reveal some interspecific effects on species detection, at both scales. In most cases, habitat use was driven more strongly by other habitat effects, such as biotic resources or anthropogenic pressures, than by interspecific pressures, even where evidence of the latter was present. Overall, our results help shed light on interspecific effects within an assemblage that has rarely been examined at this scale. We also demonstrate the effectiveness of sign-based co-occurrence modelling to describe interspecific spatial patterns of sympatric large carnivores across large scales. We conclude by discussing the implications of our findings for large carnivore conservation in modern African systems.
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Affiliation(s)
- Paolo Strampelli
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
- Lion Landscapes, Iringa, Tanzania
- Panthera, New York, NY, United States of America
| | | | - Charlotte E. Searle
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
- Lion Landscapes, Iringa, Tanzania
| | - David W. Macdonald
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
| | - Amy J. Dickman
- Department of Zoology, Wildlife Conservation Research Unit, Recanati Kaplan Centre, University of Oxford, Oxford, United Kingdom
- Lion Landscapes, Iringa, Tanzania
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Modi S, Mondol S, Ghaskadbi P, Nigam P, Habib B. Genetic evidence of differential dispersal pattern in the Asiatic wild dog: Comparing two populations with different pack sizes. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.993851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
IntroductionDispersal is a multi-causal, crucial life-history event in shaping the genetic and behavioral structure of mammals. We assessed the dispersal pattern of dholes aka Asiatic wild dog (Cuon alpinus), a social monogamous mammal at two tiger reserves of Maharashtra with different degrees of pack size and competition with tigers i.e. Tadoba-Andhari (TATR, smaller pack size, higher tiger density) and Nawegaon-Nagzira (NNTR, larger pack size, lower tiger density).MethodsWe used the microsatellite data of 174 individual genotypes (98 males and 67 females) to assess the dispersal pattern of dholes from two populations with varying pack size, tiger density, and landscape connectivity using gene flow as a proxy. We compared the population structure, pairwise F statistics, assignment index, and relatedness across a spatial scale.Results and discussionOverall, the results suggested a difference in sex-bias dispersal pattern for the two sub-populations, exhibiting significant results for female-biased dispersal in the TATR population with a smaller pack size and higher tiger density. Our study highlights the variability in sex-biased dispersal patterns in two different populations which could be the consequence of different variables such as pack size, tiger density, and geographical scale. The study warrants further quantitative investigation including several factors such as individual behavior, pack composition, pack size, tiger density, etc. In the present Anthropocene era, determining the sex bias in dispersal patterns for a short-range, pack-living carnivore will help in devising an effective conservation management plan for their long-term survival.
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Claase M, Cherry M, Apps P, McNutt J, Hansen K, Jordan N. Interpack communication in African wild dogs at long-term shared marking sites. Anim Behav 2022. [DOI: 10.1016/j.anbehav.2022.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Marneweck DG, Druce DJ, Cromsigt JPGM, le Roux E, Somers MJ. The relative role of intrinsic and extrinsic drivers in regulating population change and survival of African wild dogs (Lycaon pictus). Mamm Biol 2022. [DOI: 10.1007/s42991-022-00281-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Groom RJ, Comley J, Rabaiotti D, Wolton A, Jackson C, Ngwenya N, Watermeyer JP. African Wild Dog Reproductive Capabilities Revisited: Successfully Raising Three Litters in Less than 14 Months is Possible. AFRICAN JOURNAL OF WILDLIFE RESEARCH 2022. [DOI: 10.3957/056.052.0044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Rosemary J. Groom
- African Wildlife Conservation Fund, Chishakwe Ranch, Savé Valley Conservancy, Zimbabwe
| | - Jessica Comley
- Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University, P.O. Box 94, Grahamstown/Makhanda, 6140 South Africa
| | | | - Amy Wolton
- African Wildlife Conservation Fund, Chishakwe Ranch, Savé Valley Conservancy, Zimbabwe
| | - Craig Jackson
- Department of Terrestrial Ecology, Norwegian Institute for Nature Research, Høgskoleringen 9, 7034 Trondheim, Norway
| | - Nkosilathi Ngwenya
- African Wildlife Conservation Fund, Chishakwe Ranch, Savé Valley Conservancy, Zimbabwe
| | - Jessica P. Watermeyer
- African Wildlife Conservation Fund, Chishakwe Ranch, Savé Valley Conservancy, Zimbabwe
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Goodheart B, Creel S, Vinks MA, Banda K, Reyes de Merkle J, Kusler A, Dart C, Banda K, Becker MS, Indala P, Simukonda C, Kaluka A. African wild dog movements show contrasting responses to long and short term risk of encountering lions: analysis using dynamic Brownian bridge movement models. MOVEMENT ECOLOGY 2022; 10:16. [PMID: 35361272 PMCID: PMC8974231 DOI: 10.1186/s40462-022-00316-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Prey depletion is a threat to the world's large carnivores, and is likely to affect subordinate competitors within the large carnivore guild disproportionately. African lions limit African wild dog populations through interference competition and intraguild predation. When lion density is reduced as a result of prey depletion, wild dogs are not competitively released, and their population density remains low. Research examining distributions has demonstrated spatial avoidance of lions by wild dogs, but the effects of lions on patterns of movement have not been tested. Movement is one of the most energetically costly activities for many species and is particularly costly for cursorial hunters like wild dogs. Therefore, testing how top-down, bottom-up, and anthropogenic variables affect movement patterns can provide insight into mechanisms that limit wild dogs (and other subordinate competitors) in resource-depleted ecosystems. METHODS We measured movement rates using the motion variance from dynamic Brownian Bridge Movement Models (dBBMMs) fit to data from GPS-collared wild dogs, then used a generalized linear model to test for effects on movement of predation risk from lions, predictors of prey density, and anthropogenic and seasonal variables. RESULTS Wild dogs proactively reduced movement in areas with high lion density, but reactively increased movement when lions were immediately nearby. Predictors of prey density had consistently weaker effects on movement than lions did, but movements were reduced in the wet season and when dependent offspring were present. CONCLUSION Wild dogs alter their patterns of movement in response to lions in ways that are likely to have important energetic consequences. Our results support the recent suggestion that competitive limitation of wild dogs by lions remains strong in ecosystems where lion and wild dog densities are both low as a result of anthropogenic prey depletion. Our results reinforce an emerging pattern that movements often show contrasting responses to long-term and short-term variation in predation risk.
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Affiliation(s)
- Ben Goodheart
- Department of Ecology, Montana State University, 310 Lewis Hall, Bozeman, MT, 59717, USA.
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia.
| | - Scott Creel
- Department of Ecology, Montana State University, 310 Lewis Hall, Bozeman, MT, 59717, USA
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
- Insitutioned För Vilt, Fisk Och Miljö, Sveriges lantbruksuniversitet, Umeå, Sweden
| | - Milan A Vinks
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
- Montana Fish Wildlife and Parks, 490 North Meridian Road, Kalispell, MT, 59901, USA
| | - Kambwiri Banda
- Department of Ecology, Montana State University, 310 Lewis Hall, Bozeman, MT, 59717, USA
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
| | - Johnathan Reyes de Merkle
- Department of Ecology, Montana State University, 310 Lewis Hall, Bozeman, MT, 59717, USA
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
| | - Anna Kusler
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
| | - Chase Dart
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
| | - Kachama Banda
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
| | - Matthew S Becker
- Department of Ecology, Montana State University, 310 Lewis Hall, Bozeman, MT, 59717, USA
- Zambian Carnivore Programme, PO Box 80, Mfuwe, Eastern Province, Zambia
| | - Peter Indala
- Zambia Department of National Parks and Wildlife, Private Bag 80, Lusaka, Zambia
| | - Chuma Simukonda
- Zambia Department of National Parks and Wildlife, Private Bag 80, Lusaka, Zambia
| | - Adrian Kaluka
- Zambia Department of National Parks and Wildlife, Private Bag 80, Lusaka, Zambia
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Priority of access to food and its influence on social dynamics of an endangered carnivore. Behav Ecol Sociobiol 2022. [DOI: 10.1007/s00265-021-03115-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tallian A, Ordiz A, Metz MC, Zimmermann B, Wikenros C, Smith DW, Stahler DR, Wabakken P, Swenson JE, Sand H, Kindberg J. Of wolves and bears: Seasonal drivers of interference and exploitation competition between apex predators. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Aimee Tallian
- Norwegian Institute for Nature Research NO‐7485 Trondheim Norway
| | - Andrés Ordiz
- Grimsӧ Wildlife Research Station Department of Ecology Swedish University of Agricultural Sciences SE‐739 93 Riddarhyttan Sweden
- Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Postbox 5003, NO‐1432 Ås Norway
- Dpto. de Biodiversidad y Gestión Ambiental Área de Zoología Facultad de Ciencias Biológicas y Ambientales Universidad de León Campus de Vegazana s/n 24071 León Spain
| | - Matthew C. Metz
- Wildlife Biology Program Department of Ecosystem and Conservation Sciences University of Montana Missoula Montana 59812 USA
- Yellowstone Center for Resources Yellowstone National Park Box 168, Mammoth Hot Springs WY 82190 USA
| | - Barbara Zimmermann
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Evenstad NO‐2480 Koppang Norway
| | - Camilla Wikenros
- Grimsӧ Wildlife Research Station Department of Ecology Swedish University of Agricultural Sciences SE‐739 93 Riddarhyttan Sweden
| | - Douglas W. Smith
- Yellowstone Center for Resources Yellowstone National Park Box 168, Mammoth Hot Springs WY 82190 USA
| | - Daniel R. Stahler
- Yellowstone Center for Resources Yellowstone National Park Box 168, Mammoth Hot Springs WY 82190 USA
| | - Petter Wabakken
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology Inland Norway University of Applied Sciences Evenstad NO‐2480 Koppang Norway
| | - Jon E. Swenson
- Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Postbox 5003, NO‐1432 Ås Norway
| | - Håkan Sand
- Grimsӧ Wildlife Research Station Department of Ecology Swedish University of Agricultural Sciences SE‐739 93 Riddarhyttan Sweden
| | - Jonas Kindberg
- Norwegian Institute for Nature Research NO‐7485 Trondheim Norway
- Department of Wildlife, Fish, and Environmental Studies Swedish University of Agricultural Sciences SE‐901 83 Umeå Sweden
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Marneweck CJ, van Schalkwyk OL, Marneweck DG, Beverley G, Davies-Mostert HT, Parker DM. Reproductive state influences the degree of risk tolerance for a seasonally breeding mesopredator. Behav Ecol 2021. [DOI: 10.1093/beheco/arab018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
The risk of predation can alter the way animals perceive costs and benefits in their environment, on which foraging decisions are made. To maximize fitness, animals with offspring show the most pronounced alteration in behavior because mothers experience increased nutritional requirements and increased vulnerability to predation. Therefore, the tolerance of risk is shaped, in part, by reproductive state. Like prey species, mesopredators balance a trade-off between food and predation to maximize fitness. However, few studies have acknowledged its importance. We investigated how mesopredators may alter their space use between periods when young are and are not vulnerable. Investigating the fine-scale space use of 19 packs of African wild dogs Lycaon pictus in the Kruger National Park, we found lower risk tolerance of denning packs; they re-visited area less frequently as lion and impala density increased and thus reduced the likelihood of risky encounters by avoiding areas where both risk and reward were high. By contrast, non-denning packs re-visited area less frequently as lion density increased and impala density decreased and thus avoided areas where reward was low, especially if risk was high. These results suggest that wild dogs shift their patterns of space use when the pack is most vulnerable. Ultimately, we found evidence of decreased risk tolerance by denning packs, likely because of increased vulnerability of lactating mothers and immobile pups. More broadly, our findings suggest that risk tolerance is dependent on reproductive state for mesopredators and should be considered as a possible mechanism for other mesopredators as well.
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Affiliation(s)
- Courtney J Marneweck
- School of Biology and Environmental Sciences, University of Mpumalanga, Mbombela, 1200, South Africa
- Endangered Wildlife Trust, 27 and 28 Austin Road, Midrand, 1685, South Africa
| | - O Louis van Schalkwyk
- Office of the State Veterinarian, Department of Agriculture, Land Reform and Rural Development, PO Box 12, Skukuza, 1350, South Africa
- Department of Migration, Institute of Animal Behavior, Am Obstberg 1, D-78315 Radolfzell, Germany
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, 0110, South Africa
| | - David G Marneweck
- Endangered Wildlife Trust, 27 and 28 Austin Road, Midrand, 1685, South Africa
- Eugène Marais Chair of Wildlife Management, Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa
| | - Grant Beverley
- Endangered Wildlife Trust, 27 and 28 Austin Road, Midrand, 1685, South Africa
| | - Harriet T Davies-Mostert
- Endangered Wildlife Trust, 27 and 28 Austin Road, Midrand, 1685, South Africa
- Eugène Marais Chair of Wildlife Management, Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa
| | - Daniel M Parker
- School of Biology and Environmental Sciences, University of Mpumalanga, Mbombela, 1200, South Africa
- Wildlife and Reserve Management Research Group, Department of Zoology and Entomology, Rhodes University, Grahamstown, 6139, South Africa
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Alting BF, Bennitt E, Golabek KA, Pitcher BJ, McNutt JW, Wilson AM, Bates H, Jordan NR. The characteristics and consequences of African wild dog (Lycaon pictus) den site selection. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-03047-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Davis RS, Yarnell RW, Gentle LK, Uzal A, Mgoola WO, Stone EL. Prey availability and intraguild competition regulate the spatiotemporal dynamics of a modified large carnivore guild. Ecol Evol 2021; 11:7890-7904. [PMID: 34188859 PMCID: PMC8216965 DOI: 10.1002/ece3.7620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/08/2021] [Accepted: 04/13/2021] [Indexed: 11/10/2022] Open
Abstract
Effective conservation management requires an understanding of the spatiotemporal dynamics driving large carnivore density and resource partitioning. In African ecosystems, reduced prey populations and the loss of competing guild members, most notably lion (Panthera leo), are expected to increase the levels of competition between remaining carnivores. Consequently, intraguild relationships can be altered, potentially increasing the risk of further population decline. Kasungu National Park (KNP), Malawi, is an example of a conservation area that has experienced large-scale reductions in both carnivore and prey populations, leaving a resident large carnivore guild consisting of only leopard (Panthera pardus) and spotted hyena (Crocuta crocuta). Here, we quantify the spatiotemporal dynamics of these two species and their degree of association, using a combination of co-detection modeling, time-to-event analyses, and temporal activity patterns from camera trap data. The detection of leopard and spotted hyena was significantly associated with the detection of preferred prey and competing carnivores, increasing the likelihood of species interaction. Temporal analyses revealed sex-specific differences in temporal activity, with female leopard activity patterns significantly different to those of spotted hyena and male conspecifics. Heightened risk of interaction with interspecific competitors and male conspecifics may have resulted in female leopards adopting temporal avoidance strategies to facilitate coexistence. Female leopard behavioral adaptations increased overall activity levels and diurnal activity rates, with potential consequences for overall fitness and exposure to sources of mortality. As both species are currently found at low densities in KNP, increased risk of competitive interactions, which infer a reduction in fitness, could have significant implications for large carnivore demographics. The protection of remaining prey populations is necessary to mitigate interspecific competition and avoid further alterations to the large carnivore guild.
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Affiliation(s)
- Robert S. Davis
- School of Animal, Rural and Environmental SciencesNottingham Trent UniversityBrackenhurst CampusSouthwellUK
- Conservation Research Africa & Carnivore Research MalawiLilongweMalawi
| | - Richard W. Yarnell
- School of Animal, Rural and Environmental SciencesNottingham Trent UniversityBrackenhurst CampusSouthwellUK
| | - Louise K. Gentle
- School of Animal, Rural and Environmental SciencesNottingham Trent UniversityBrackenhurst CampusSouthwellUK
| | - Antonio Uzal
- School of Animal, Rural and Environmental SciencesNottingham Trent UniversityBrackenhurst CampusSouthwellUK
| | | | - Emma L. Stone
- Conservation Research Africa & Carnivore Research MalawiLilongweMalawi
- Department of Applied SciencesUniversity of the West of EnglandBristolUK
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Bhandari A, Ghaskadbi P, Nigam P, Habib B. Dhole pack size variation: Assessing the effect of Prey availability and Apex predator. Ecol Evol 2021; 11:4774-4785. [PMID: 33976847 PMCID: PMC8093734 DOI: 10.1002/ece3.7380] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 01/29/2021] [Accepted: 02/15/2021] [Indexed: 01/31/2023] Open
Abstract
In multipredator systems, group sizes of social carnivores are shaped by the asymmetric intraguild interactions. Subordinate social carnivores experience low recruitment rates as an outcome of predation pressure. In South and Southeast Asia, the Tiger (Panthera tigris), Dhole (Cuon alpinus), and Leopard (Panthera pardus) form a widely distributed sympatric guild of large carnivores, wherein tigers are the apex predators followed by dhole and leopard. In this study, we attempted to understand the variation in pack size of a social carnivore, the dhole, at two neighboring sites in the Central Indian landscape. We further evaluated local-scale patterns of variation in pack size at a larger scale by doing a distribution-wide assessment across the dhole ranging countries. At the local scale, we found an inverse relationship between the density of tiger and pack size of dhole while accounting for variability in resources and habitat heterogeneity. Larger dhole packs (16.8 ± 3.1) were observed at the site where the tiger density was low (0.46/100 km2), whereas a smaller pack size (6.4 ± 1.3) was observed in the site with high tiger density (5.36/100 km2). Our results for the distribution-wide assessment were concordant with local-scale results, showing a negative association of pack size with the tiger densities (effect size -0.77) and a positive association with the prey abundance (effect size 0.64). The study advances our understanding to answer the age-old question of "what drives the pack size of social predators in a multipredator system?" This study also highlights the importance of understanding demographic responses of subordinate predator for varying competitor densities, often helpful in making informed decisions for conservation and management strategies such as population recovery and translocation of species.
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Affiliation(s)
- Aishwarya Bhandari
- Department of Animal Ecology and Conservation BiologyWildlife Institute of IndiaDehradunIndia
| | - Pallavi Ghaskadbi
- Department of Animal Ecology and Conservation BiologyWildlife Institute of IndiaDehradunIndia
| | - Parag Nigam
- Department of Wildlife Health and ManagementWildlife Institute of IndiaDehradunIndia
| | - Bilal Habib
- Department of Animal Ecology and Conservation BiologyWildlife Institute of IndiaDehradunIndia
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Davies AB, Tambling CJ, Marneweck DG, Ranc N, Druce DJ, Cromsigt JPGM, le Roux E, Asner GP. Spatial heterogeneity facilitates carnivore coexistence. Ecology 2021; 102:e03319. [PMID: 33636010 DOI: 10.1002/ecy.3319] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/25/2020] [Accepted: 12/06/2020] [Indexed: 01/30/2023]
Abstract
Competitively dominant carnivore species can limit the population sizes and alter the behavior of inferior competitors. Established mechanisms that enable carnivore coexistence include spatial and temporal avoidance of dominant predator species by subordinates, and dietary niche separation. However, spatial heterogeneity across landscapes could provide inferior competitors with refuges in the form of areas with lower competitor density and/or locations that provide concealment from competitors. Here, we combine temporally overlapping telemetry data from dominant lions (Panthera leo) and subordinate African wild dogs (Lycaon pictus) with high-resolution remote sensing in an integrated step selection analysis to investigate how fine-scaled landscape heterogeneity might facilitate carnivore coexistence in South Africa's Hluhluwe-iMfolozi Park, where both predators occur at exceptionally high densities. We ask whether the primary lion-avoidance strategy of wild dogs is spatial avoidance of lions or areas frequented by lions, or if wild dogs selectively use landscape features to avoid detection by lions. Within this framework, we also test whether wild dogs rely on proactive or reactive responses to lion risk. In contrast to previous studies finding strong spatial avoidance of lions by wild dogs, we found that the primary wild dog lion-avoidance strategy was to select landscape features that aid in avoidance of lion detection. This habitat selection was routinely used by wild dogs, and especially when in areas and during times of high lion-encounter risk, suggesting a proactive response to lion risk. Our findings suggest that spatial landscape heterogeneity could represent an alternative mechanism for carnivore coexistence, especially as ever-shrinking carnivore ranges force inferior competitors into increased contact with dominant species.
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Affiliation(s)
- Andrew B Davies
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Craig J Tambling
- Department of Zoology and Entomology, University of Fort Hare, Alice, South Africa
| | - David G Marneweck
- Eugène Marais Chair of Wildlife Management, Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, South Africa.,Endangered Wildlife Trust, Johannesburg, South Africa.,Wildlife Ecology Lab, School of Natural Resource Management, Nelson Mandela University, Port Elizabeth, South Africa
| | - Nathan Ranc
- Environmental Studies Department, University of California-Santa Cruz, Santa Cruz, California, USA
| | - Dave J Druce
- Ezemvelo KZN Wildlife, Hluhluwe-iMfolozi Park, South Africa.,School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Joris P G M Cromsigt
- Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.,Department of Zoology, Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, South Africa.,Faculty of Geosciences, Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands
| | - Elizabeth le Roux
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Gregory P Asner
- Center for Global Discovery and Conservation Science, Arizona State University, Tempe, Arizona, USA
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17
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Rafiq K, Jordan NR, Wilson AM, McNutt JW, Hayward MW, Meloro C, Wich SA, Golabek KA. Spatio‐temporal factors impacting encounter occurrences between leopards and other large African predators. J Zool (1987) 2019. [DOI: 10.1111/jzo.12746] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Rafiq
- School of Natural Sciences and Psychology Liverpool John Moores University Liverpool UK
- Botswana Predator Conservation Trust Maun Botswana
| | - N. R. Jordan
- Botswana Predator Conservation Trust Maun Botswana
- Centre for Ecosystem Science University of New South Wales Sydney New South Wales Australia
- Taronga Conservation Society Sydney New South Wales Australia
| | - A. M. Wilson
- Structure and Motion Lab Royal Veterinary College University of London Hatfield Herts UK
| | - J. W. McNutt
- Botswana Predator Conservation Trust Maun Botswana
| | - M. W. Hayward
- School of Environmental and Life Sciences University of Newcastle Newcastle New South Wales Australia
| | - C. Meloro
- School of Natural Sciences and Psychology Liverpool John Moores University Liverpool UK
| | - S. A. Wich
- School of Natural Sciences and Psychology Liverpool John Moores University Liverpool UK
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18
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Spatial partitioning by a subordinate carnivore is mediated by conspecific overlap. Oecologia 2019; 191:531-540. [PMID: 31535256 DOI: 10.1007/s00442-019-04512-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 09/10/2019] [Indexed: 10/26/2022]
Abstract
There are several hypotheses that could explain territory size in mammals, including the resource dispersion hypothesis (RDH), the intruder pressure hypothesis (IPH), and the intraguild predation hypothesis (IGPH). In this study, we tested predictions of these three hypotheses regarding territories of 19 packs of endangered African wild dogs (Lycaon pictus) over 2 years in the Kruger National Park, South Africa. If territory size was supported by the RDH, then we would observe (1) wild dog territories would be larger when resource patches were more dispersed, (2) pack sizes would be larger when resource patches were rich, and (3) pack size would not affect territory size. If supported by the IPH, then we would observe (4) larger territories would experience less intrusions, and (5) there would be an increase in territory overlap in areas of low resource dispersion. Finally, if supported by the IGPH, we would observe (6) territories would be larger in areas of higher lion (Panthera leo) density, as evidence of a spatial avoidance strategy. We found that the IGPH was fully supported (6), the IPH half supported (5), and the RDH partially supported (1 and 3), where we found spatial partitioning of wild dogs with lions, potentially mediated by resources and territory overlap with conspecifics. Ultimately, our results show that subordinate carnivores must balance a trade-off between dominant interspecific competitors and conspecifics to successfully coexist in areas with dominant carnivores.
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Vogel JT, Somers MJ, Venter JA. Niche overlap and dietary resource partitioning in an African large carnivore guild. J Zool (1987) 2019. [DOI: 10.1111/jzo.12706] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- John T. Vogel
- School of Natural Resource Management, Faculty of Science, George Campus Nelson Mandela University George South Africa
- Eastern Cape Parks and Tourism Agency East London South Africa
| | - Michael J. Somers
- Department of Zoology and Entomology Eugène Marais Chair of Wildlife Management, Mammal Research Institute, Centre for Invasion Biology University of Pretoria Pretoria South Africa
| | - Jan A. Venter
- School of Natural Resource Management, Faculty of Science, George Campus Nelson Mandela University George South Africa
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20
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Jackson CR, Masenga EH, Mjingo EE, Davies AB, Fossøy F, Fyumagwa RD, Røskaft E, May RF. No evidence of handling-induced mortality in Serengeti's African wild dog population. Ecol Evol 2019; 9:1110-1118. [PMID: 30805144 PMCID: PMC6374660 DOI: 10.1002/ece3.4798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 11/05/2018] [Accepted: 11/09/2018] [Indexed: 12/12/2022] Open
Abstract
The disappearance of an endangered African wild dog population from Serengeti National Park (SNP) led to international debate centered around one question: were researchers to blame? The "Burrows' hypothesis" postulated that stress induced by research-related immobilization and handling reactivated a latent rabies virus, eliminating the population. Insufficient data inhibited hypothesis testing, but since wild dogs persisted alongside SNP and have been studied since 2005, the hypothesis can be tested 25 years after its proposition. To be supported, wild dog immobilization interventions should have resulted in high mortality rates. However, 87.6% of 121 handled wild dogs (2006-2016) survived >12 months post-handling. Some argued that viral reactivation would necessitate long-term stress. Following immobilization, 67 animals were captured, transported, and held in a translocation enclosure. Despite the longer-term stress, 95.5% survived >12 months. Furthermore, the stable number of wild dog packs in the ecosystem over the past decade, and lack of recolonization of SNP, strongly oppose Burrows' hypothesis. Instead, factors such as heightened levels of interspecific competition are likely to have contributed to the wild dog disappearance and subsequent avoidance of the Serengeti plains. Handling and radio telemetry are invaluable when studying elusive endangered species, yielding information pertinent to their conservation and management, and had no effect on Serengeti wild dog survival.
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Affiliation(s)
| | | | | | - Andrew B. Davies
- Department of Global EcologyCarnegie Institution for ScienceStanfordCalifornia
| | - Frode Fossøy
- Norwegian Institute for Nature Research (NINA)TrondheimNorway
- Tanzania Wildlife Research Institute (TAWIRI)ArushaTanzania
| | | | - Eivin Røskaft
- Department of BiologyNorwegian University of Science and Technology (NTNU)TrondheimNorway
| | - Roel F. May
- Norwegian Institute for Nature Research (NINA)TrondheimNorway
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21
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Gese EM, Waddell WT, Terletzky PA, Lucash CF, McLellan SR, Behrns SK. Cross-fostering as a conservation tool to augment endangered carnivore populations. J Mammal 2018. [DOI: 10.1093/jmammal/gyy087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Cross-fostering offspring with nonbiological parents could prove useful to augment populations of endangered carnivores. We used cross-fostering to augment captive-born and wild-born litters for the endangered red wolf (Canis rufus). Between 1987 and 2016, 23 cross-fostering events occurred involving captive-born pups fostered into captive litters (n = 8 events) and captive-born pups fostered into wild recipient litters (n = 15 events). Percentage of pups surviving 3 and 12 months was 91.7% for captive-born pups fostered into captive recipient litters. For pups fostered into wild litters, percentage of pups surviving 5 months was > 94% among fostered pups (pups fostered into a wild red wolf litter or replaced a hybrid litter), pups in recipient litters (wild-born litters receiving fostered pups), and pups in control litters (wild-born litters not in a fostering event) when using pups with known fates. Including pups with unknown fates as deaths, percentage of pups surviving 5 months was > 54% among fostered pups, pups in recipient litters, and pups in control litters. Among wild litters, percentage of pups surviving 12 months was > 82% among fostered pups, pups in recipient litters, and pups in control litters when using pups with known fates. Including pups with unknown fates as deaths, percentage of pups surviving 12 months was > 48% among fostered pups, pups in recipient litters, and pups in control litters. Although survival to 12 months was similar among the groups, average life span was different with pups in control litters living 3.3 years, pups in recipient litters living 4.6 years, and fostered pups living 5.6 years. Of fostered pups surviving > 12 months in the wild, 9 animals whelped or sired 26 litters. Cross-fostering was successful at augmenting litter size for red wolves without any deleterious effects on recipient litters, illustrating fostering as a tool for increasing populations of endangered carnivores.
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Affiliation(s)
- Eric M Gese
- United States Department of Agriculture, Wildlife Services, National Wildlife Research Center, Department of Wildland Resources, Utah State University, Logan, UT, USA
| | | | | | - Chris F Lucash
- United States Fish and Wildlife Service, Manteo, NC, USA
| | - Scott R McLellan
- Maine Department of Inland Fisheries and Wildlife, Greenville, ME, USA
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Jackson CR, Groom RJ, Jordan NR, McNutt JW. The effect of relatedness and pack size on territory overlap in African wild dogs. MOVEMENT ECOLOGY 2017; 5:10. [PMID: 28417004 PMCID: PMC5392232 DOI: 10.1186/s40462-017-0099-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 03/09/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Spacing patterns mediate competitive interactions between conspecifics, ultimately increasing fitness. The degree of territorial overlap between neighbouring African wild dog (Lycaon pictus) packs varies greatly, yet the role of factors potentially affecting the degree of overlap, such as relatedness and pack size, remain unclear. We used movement data from 21 wild dog packs to calculate the extent of territory overlap (20 dyads). RESULTS On average, unrelated neighbouring packs had low levels of overlap restricted to the peripheral regions of their 95% utilisation kernels. Related neighbours had significantly greater levels of peripheral overlap. Only one unrelated dyad included overlap between 75%-75% kernels, but no 50%-50% kernels overlapped. However, eight of 12 related dyads overlapped between their respective 75% kernels and six between the frequented 50% kernels. Overlap between these more frequented kernels confers a heightened likelihood of encounter, as the mean utilisation intensity per unit area within the 50% kernels was 4.93 times greater than in the 95% kernels, and 2.34 times greater than in the 75% kernels. Related packs spent significantly more time in their 95% kernel overlap zones than did unrelated packs. Pack size appeared to have little effect on overlap between related dyads, yet among unrelated neighbours larger packs tended to overlap more onto smaller packs' territories. However, the true effect is unclear given that the model's confidence intervals overlapped zero. CONCLUSIONS Evidence suggests that costly intraspecific aggression is greatly reduced between related packs. Consequently, the tendency for dispersing individuals to establish territories alongside relatives, where intensively utilised portions of ranges regularly overlap, may extend kin selection and inclusive fitness benefits from the intra-pack to inter-pack level. This natural spacing system can affect survival parameters and the carrying capacity of protected areas, having important management implications for intensively managed populations of this endangered species.
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Affiliation(s)
- Craig R. Jackson
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Terrestrial Ecology, Norwegian Institute for Nature Research, Sluppen, PO Box 5685, NO-7485 Trondheim, Norway
| | - Rosemary J. Groom
- Department of Zoology, University of Johannesburg, Johannesburg, South Africa
- African Wildlife Conservation Fund, Savé Valley Conservancy, Harare, Zimbabwe
| | - Neil R. Jordan
- Botswana Predator Conservation Trust, Maun, Botswana
- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales (UNSW), Sydney, NSW 2052 Australia
- Taronga Conservation Society Australia, Taronga Western Plains Zoo, Wildlife Reproduction Centre, Obley Road, Dubbo, NSW 2830 Australia
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23
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Goldingay RL, Keohan J. Population density of the eastern pygmy-possum in a heath–woodland habitat. AUST J ZOOL 2017. [DOI: 10.1071/zo18026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The eastern pygmy-possum (Cercartetus nanus) has posed a challenge in attempts to describe its population density due to low rates of capture, preference for patchy habitats and periodic influxes of subadult individuals. We conducted a mark–recapture study of this species using a grid of nest boxes in a 9-ha patch of banksia heath–woodland. We captured 54 adults across the two years of our study. We estimated the density of adult pygmy-possums to be 1.5–4.2 ha–1 from different population models. This is substantially lower than previous estimates in equivalent habitat because we focussed on adults and recognised that they were not confined to the area bounded by our grid. We captured 36 subadults over the two years but they could not be reliably modelled due to extremely low recapture rates, which reflect high rates of dispersal and also mortality. For this reason, only the number of adults should be used to characterise populations of this species. Further study is required to investigate population dynamics over time and to describe the density of eastern pygmy-possums in other habitats.
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