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Webber QM, Ferraro K, Hendrix J, Vander Wal E. What do caribou eat? A review of the literature on caribou diet. CAN J ZOOL 2022. [DOI: 10.1139/cjz-2021-0162] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Historically the study of diet caribou and reindeer (Rangifer tarandus (Gmelin, 1788)) has been specific to herds and few comprehensive circumpolar analyses of Rangifer diet exist. As a result, the importance of certain diet items may play an outsized role in the caribou diet zeitgeist, e.g., lichen. It is incumbent to challenge this notion and test the relevant importance of various diet items within the context of prevailing hypotheses. We provide a systematic overview of 30 caribou studies reporting caribou diet and test biologically relevant hypotheses about spatial and temporal dietary variation. Our results indicate that in the winter caribou primarily consume lichen, but in warmer seasons, and primary productivity is lower, caribou primarily consume graminoids and other vascular plants. In more productive environments, where caribou have more competitors and predators, consumption of lichen increased. Overall, our description of caribou diet reveals that caribou diet is highly variable, but in circumstances where they can consume vascular plants, they will. As climate change affects Boreal and Arctic ecosystems, the type and volume of food consumed by caribou has become an increasingly important focus for conservation and management of caribou.
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Affiliation(s)
- Quinn M.R. Webber
- Memorial University of Newfoundland, 7512, Cognitive and Behavioural Ecology, St. John's, Newfoundland and Labrador, Canada
- University of Colorado Boulder, 1877, Department of Ecology and Evolutionary Biology, Boulder, Colorado, United States
| | - Kristy Ferraro
- Yale University, 5755, School of the Environment, New Haven, Connecticut, United States
| | - Jack Hendrix
- Memorial University of Newfoundland, 7512, Cognitive and Behavioural Ecology, St. John's, Newfoundland and Labrador, Canada
| | - Eric Vander Wal
- Memorial University of Newfoundland, 7512, Biology, 232 Elizabeth Ave, Saint John's, Newfoundland and Labrador, Canada, A1B 3X9,
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Mitchell G, Wilson PJ, Manseau M, Redquest B, Patterson BR, Rutledge LY. DNA metabarcoding of faecal pellets reveals high consumption of yew ( Taxus spp.) by caribou ( Rangifer tarandus) in a lichen-poor environment. Facets (Ott) 2022. [DOI: 10.1139/facets-2021-0071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Woodland caribou ( Rangifer tarandus caribou) are threatened in Canada because of the drastic decline in population size caused primarily by human-induced landscape changes that decrease habitat and increase predation risk. Conservation efforts have largely focused on reducing predators and protecting critical habitat, whereas research on dietary niches and the role of potential food constraints in lichen-poor environments is limited. To improve our understanding of dietary niche variability, we used a next-generation sequencing approach with metabarcoding of DNA extracted from faecal pellets of woodland caribou located on Lake Superior in lichen-rich (mainland) and lichen-poor (island) environments. Amplicon sequencing of fungal ITS2 region revealed lichen-associated fungi as predominant in samples from both populations, but amplification at the chloroplast trnL region, which was only successful on island samples, revealed primary consumption of yew ( Taxus spp.) based on relative read abundance (83.68%) with dogwood ( Cornus spp.; 9.67%) and maple ( Acer spp.; 4.10%) also prevalent. These results suggest that conservation efforts for caribou need to consider the availability of food resources beyond lichen to ensure successful outcomes. More broadly, we provide a reliable methodology for assessing ungulate diet from archived faecal pellets that could reveal important dietary shifts over time in response to climate change.
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Affiliation(s)
- Greniqueca Mitchell
- Biology Department, Trent University, Life and Health Sciences Building, 2089 East Bank Drive, Peterborough, ON K9L 1Z8, Canada
| | - Paul J. Wilson
- Biology Department, Trent University, Life and Health Sciences Building, 2089 East Bank Drive, Peterborough, ON K9L 1Z8, Canada
| | - Micheline Manseau
- Biology Department, Trent University, Life and Health Sciences Building, 2089 East Bank Drive, Peterborough, ON K9L 1Z8, Canada
- Landscape Science and Technology Division, Environment and Climate Change Canada, 1125 Colonel By Drive, Ottawa, ON K1S 5R1, Canada
| | - Bridgett Redquest
- Biology Department, Trent University, Life and Health Sciences Building, 2089 East Bank Drive, Peterborough, ON K9L 1Z8, Canada
| | - Brent R. Patterson
- Ontario Ministry of Natural Resources and Forestry, Trent University, DNA Building, Peterborough, ON K9L 1Z8, Canada
| | - Linda Y. Rutledge
- Biology Department, Trent University, Life and Health Sciences Building, 2089 East Bank Drive, Peterborough, ON K9L 1Z8, Canada
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Walker PD, Rodgers AR, Shuter JL, Thompson ID, Fryxell JM, Cook JG, Cook RC, Merrill EH. Comparison of Woodland Caribou Calving Areas Determined by Movement Patterns Across Northern Ontario. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21961] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Philip D. Walker
- Department of Biological Sciences University of Alberta Edmonton AB T6G 2E9 Canada
| | - Arthur R. Rodgers
- Ontario Ministry of Natural Resources and Forestry Centre for Northern Forest Ecosystem Research 103‐421 James Street South Thunder Bay ON P7E 2V6 Canada
| | - Jennifer L. Shuter
- Ontario Ministry of Natural Resources and Forestry Centre for Northern Forest Ecosystem Research 103‐421 James Street South Thunder Bay ON P7E 2V6 Canada
| | - Ian D. Thompson
- Canadian Forest Service (Retired) 1219 Queen Street E, Sault Ste. Marie ON P6A 2E5 Canada
| | - John M. Fryxell
- Department of Integrative Biology University of Guelph Guelph ON N1G 2W1 Canada
| | - John G. Cook
- National Council for Air and Stream Improvement Forestry and Range Science Laboratory 1401 Gekeler Lane La Grande OR 97850 USA
| | - Rachel C. Cook
- National Council for Air and Stream Improvement Forestry and Range Science Laboratory 1401 Gekeler Lane La Grande OR 97850 USA
| | - Eveyln H. Merrill
- Department of Biological Sciences University of Alberta Edmonton AB T6G 2E9 Canada
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McNeill E, Thompson I, Wiebe P, Street G, Shuter J, Rodgers A, Fryxell J. Multi-scale foraging decisions made by woodland caribou ( Rangifer tarandus caribou) in summer. CAN J ZOOL 2020. [DOI: 10.1139/cjz-2019-0197] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Multi-scale selection patterns can be understood from two perspectives: coarse-scale patterns as the summation of fine-scale patterns (scaling-up), or as a hierarchy produced from multiple contributory factors with differential effects on organismal fitness (hierarchical). We examined woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) selection of foraging locations across two spatiotemporal scales to test whether selection patterns between them were consistent (scaling-up) or different (hierarchical) to determine which framework most accurately describes their foraging behaviour. Seven adult female woodland caribou were equipped with GPS telemetry radio collars outfitted with high-definition video cameras that recorded woodland caribou foraging choices throughout the summer. Fine-scale data from videos combined with direct measurements in the field along movement trajectories obtained from GPS fixes were used to estimate (i) feeding station selection and (ii) food patch selection. We estimated resource selection functions for each scale following a use–availability structure. Woodland caribou exhibited resource selection at both scales. Apart from selection for species of the lichen Cladina (Nyl.) Nyl. and patches associated with high abundance of Cladina, few patterns were consistent across both scales. Our study suggests that even at very fine scales, woodland caribou selection for foraging locations is hierarchical in nature.
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Affiliation(s)
- E.P. McNeill
- Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - I.D. Thompson
- Great Lakes Forestry Centre, Canadian Forest Service, 1219 Queen Street East, Sault Ste. Marie, ON P6A 2E5, Canada
| | - P.A. Wiebe
- Great Lakes Forestry Centre, Canadian Forest Service, 1219 Queen Street East, Sault Ste. Marie, ON P6A 2E5, Canada
| | - G.M. Street
- Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - J. Shuter
- Centre for Northern Forest Ecosystem Research, Ontario Ministry of Natural Resources and Forestry, Thunder Bay, ON P7B 5E1, Canada
| | - A.R. Rodgers
- Centre for Northern Forest Ecosystem Research, Ontario Ministry of Natural Resources and Forestry, Thunder Bay, ON P7B 5E1, Canada
| | - J.M. Fryxell
- Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
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Fryxell JM, Avgar T, Liu B, Baker JA, Rodgers AR, Shuter J, Thompson ID, Reid DEB, Kittle AM, Mosser A, Newmaster SG, Nudds TD, Street GM, Brown GS, Patterson B. Anthropogenic Disturbance and Population Viability of Woodland Caribou in Ontario. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21829] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- John M. Fryxell
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Tal Avgar
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Boyan Liu
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - James A. Baker
- Ontario Ministry of Natural Resources and ForestryWildlife Research and Monitoring Section 300 Water Street, Peterborough Ontario K9J 8M5 Canada
| | - Arthur R. Rodgers
- Ontario Ministry of Natural Resources and ForestryCentre for Northern Forest Ecosystem Research 435 James Street Thunder‐Bay Ontario P7E 2VE Canada
| | - Jennifer Shuter
- Ontario Ministry of Natural Resources and ForestryCentre for Northern Forest Ecosystem Research 435 James Street Thunder‐Bay Ontario P7E 2VE Canada
| | - Ian D. Thompson
- Canadian Forest Service 1219 Queen Street East, Sault Ste. Marie Ontario P6A 2E5 Canada
| | - Douglas E. B. Reid
- Ontario Ministry of Natural Resources and ForestryCentre for Northern Forest Ecosystem Research 435 James Street Thunder‐Bay Ontario P7E 2VE Canada
| | - Andrew M. Kittle
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Anna Mosser
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Steven G. Newmaster
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Tom D. Nudds
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Garrett M. Street
- Department of Integrative BiologyUniversity of Guelph 50 Stone Road E., Guelph Ontario N1G 2W1 Canada
| | - Glen S. Brown
- Ontario Ministry of Natural Resources and ForestryWildlife Research and Monitoring Section 300 Water Street, Peterborough Ontario K9J 8M5 Canada
| | - Brent Patterson
- Ontario Ministry of Natural Resources and ForestryWildlife Research and Monitoring Section 300 Water Street, Peterborough Ontario K9J 8M5 Canada
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Karelus DL, McCown JW, Scheick BK, van de Kerk M, Bolker BM, Oli MK. Incorporating movement patterns to discern habitat selection: black bears as a case study. WILDLIFE RESEARCH 2019. [DOI: 10.1071/wr17151] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context Animals’ use of space and habitat selection emerges from their movement patterns, which are, in turn, determined by their behavioural or physiological states and extrinsic factors. Aim The aims of the present study were to investigate animal movement and incorporate the movement patterns into habitat selection analyses using Global Positioning System (GPS) location data from 16 black bears (Ursus americanus) in a fragmented area of Florida, USA. Methods Hidden Markov models (HMMs) were used to discern the movement patterns of the bears. These results were then used in step-selection functions (SSFs) to evaluate habitat selection patterns and the factors influencing these patterns. Key results HMMs revealed that black bear movement patterns are best described by three behavioural states: (1) resting (very short step-lengths and large turning angles); (2) encamped (moderate step-lengths and large turning angles); and (3) exploratory (long step-lengths and small turning angles). Bears selected for forested wetlands and marsh wetlands more than any other land cover type, and generally avoided urban areas in all seasons and when in encamped and exploratory behavioural states. Bears also chose to move to locations farther away from major roads. Conclusions Because habitat selection is influenced by how animals move within landscapes, it is essential to consider animals’ movement patterns when making inferences about habitat selection. The present study achieves this goal by using HMMs to first discern black bear movement patterns and associated parameters, and by using these results in SSFs to investigate habitat selection patterns. Thus, the methodological framework developed in this study effectively incorporates state-specific movement patterns while making inferences regarding habitat selection. The unified methodological approach employed here will contribute to an improved understanding of animal ecology as well as informed management decisions. Implications Conservation plans focused on preserving forested wetlands would benefit bears by not only providing habitat for resting and foraging, but also by providing connectivity through fragmented landscapes. Additionally, the framework could be applied to species that follow annual cycles and may provide a tool for investigating how animals are using dispersal corridors.
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Bruggeman JE, Swem T, Andersen DE, Kennedy PL, Nigro D. Incorporating productivity as a measure of fitness into models of breeding area quality of Arctic peregrine falcons. WILDLIFE BIOLOGY 2018. [DOI: 10.2981/wlb.00475] [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)
- Jason E. Bruggeman
- J. E. Bruggeman , Minnesota Cooperative Fish and Wildlife Research Unit, Dept of Fisheries, Wildlife and Conservation Biology, Univ. of Minnesota, St. Paul, MN 55108, USA. Present address: 4157 West 145th Street, Savage, MN 55378,
| | - Ted Swem
- T. Swem, US Fish and Wildlife Service, Fairbanks, AK, USA
| | - David E. Andersen
- D. E. Andersen, US Geological Survey, Minnesota Cooperative Fish and Wildlife Research Unit, St. Paul, MN, USA
| | - Patricia L. Kennedy
- P. L. Kennedy, Eastern Oregon Agricultural Research Center, Dept of Fisheries and Wildlife, Oregon State Univ., Union, OR, USA
| | - Debora Nigro
- D. Nigro, Bureau of Land Management, Fairbanks, AK, USA
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Viejou R, Avgar T, Brown GS, Patterson BR, Reid DEB, Rodgers AR, Shuter J, Thompson ID, Fryxell JM. Woodland caribou habitat selection patterns in relation to predation risk and forage abundance depend on reproductive state. Ecol Evol 2018; 8:5863-5872. [PMID: 29938099 PMCID: PMC6010817 DOI: 10.1002/ece3.4124] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 03/30/2018] [Accepted: 04/02/2018] [Indexed: 11/18/2022] Open
Abstract
The ideal free distribution assumes that animals select habitats that are beneficial to their fitness. When the needs of dependent offspring differ from those of the parent, ideal habitat selection patterns could vary with the presence or absence of offspring. We test whether habitat selection depends on reproductive state due to top-down or bottom-up influences on the fitness of woodland caribou (Rangifer tarandus caribou), a threatened, wide-ranging herbivore. We combined established methods of fitting resource and step selection functions derived from locations of collared animals in Ontario with newer techniques, including identifying calf status from video collar footage and seasonal habitat selection analysis through latent selection difference functions. We found that females with calves avoided predation risk and proximity to roads more strongly than females without calves within their seasonal ranges. At the local scale, females with calves avoided predation more strongly than females without calves. Females with calves increased predation avoidance but not selection for food availability upon calving, whereas females without calves increased selection for food availability across the same season. These behavioral responses suggest that habitat selection by woodland caribou is influenced by reproductive state, such that females with calves at heel use habitat selection to offset the increased vulnerability of their offspring to predation risk.
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Affiliation(s)
- Rebecca Viejou
- Department of Integrative BiologyUniversity of GuelphGuelphONCanada
| | - Tal Avgar
- Department of Integrative BiologyUniversity of GuelphGuelphONCanada
| | - Glen S. Brown
- Ontario Ministry of Natural Resources and ForestrySault Ste. MarieONCanada
| | - Brent R. Patterson
- Wildlife Research and Development SectionOntario Ministry of Natural Resources and ForestryPeterboroughONCanada
| | - Doug E. B. Reid
- Centre for Northern Forest Ecosystem ResearchOntario Ministry of Natural Resources and ForestryThunder BayONCanada
| | - Arthur R. Rodgers
- Centre for Northern Forest Ecosystem ResearchOntario Ministry of Natural Resources and ForestryThunder BayONCanada
| | - Jennifer Shuter
- Centre for Northern Forest Ecosystem ResearchOntario Ministry of Natural Resources and ForestryThunder BayONCanada
| | | | - John M. Fryxell
- Department of Integrative BiologyUniversity of GuelphGuelphONCanada
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Raponi M, Beresford DV, Schaefer JA, Thompson ID, Wiebe PA, Rodgers AR, Fryxell JM. Biting flies and activity of caribou in the boreal forest. J Wildl Manage 2018. [DOI: 10.1002/jwmg.21427] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Marco Raponi
- Environmental and Life Sciences Graduate Program; Trent University; 1600 West Bank Drive Peterborough ON K9L 0G2 Canada
| | - David V. Beresford
- Biology Department; Trent University; 1600 West Bank Drive Peterborough ON K9L 0G2 Canada
| | - James A. Schaefer
- Biology Department; Trent University; 1600 West Bank Drive Peterborough ON K9L 0G2 Canada
| | - Ian D. Thompson
- Canadian Forest Service; 1219 Queen St. East Sault Ste. Marie ON P6A 2E5 Canada
| | - Philip A. Wiebe
- Canadian Forest Service; 1219 Queen St. East Sault Ste. Marie ON P6A 2E5 Canada
| | - Arthur R. Rodgers
- Ontario Ministry of Natural Resources and Forestry; Centre for Northern Forest Ecosystem Research; 103-421 James Street South Thunder Bay ON P7E 2V6 Canada
| | - John M. Fryxell
- Department of Integrative Biology; University of Guelph; 50 Stone Road East Guelph ON N1G 2W1 Canada
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Newton EJ, Patterson BR, Anderson ML, Rodgers AR, Vander Vennen LM, Fryxell JM. Compensatory selection for roads over natural linear features by wolves in northern Ontario: Implications for caribou conservation. PLoS One 2017; 12:e0186525. [PMID: 29117234 PMCID: PMC5695599 DOI: 10.1371/journal.pone.0186525] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 10/03/2017] [Indexed: 11/21/2022] Open
Abstract
Woodland caribou (Rangifer tarandus caribou) in Ontario are a threatened species that have experienced a substantial retraction of their historic range. Part of their decline has been attributed to increasing densities of anthropogenic linear features such as trails, roads, railways, and hydro lines. These features have been shown to increase the search efficiency and kill rate of wolves. However, it is unclear whether selection for anthropogenic linear features is additive or compensatory to selection for natural (water) linear features which may also be used for travel. We studied the selection of water and anthropogenic linear features by 52 resident wolves (Canis lupus x lycaon) over four years across three study areas in northern Ontario that varied in degrees of forestry activity and human disturbance. We used Euclidean distance-based resource selection functions (mixed-effects logistic regression) at the seasonal range scale with random coefficients for distance to water linear features, primary/secondary roads/railways, and hydro lines, and tertiary roads to estimate the strength of selection for each linear feature and for several habitat types, while accounting for availability of each feature. Next, we investigated the trade-off between selection for anthropogenic and water linear features. Wolves selected both anthropogenic and water linear features; selection for anthropogenic features was stronger than for water during the rendezvous season. Selection for anthropogenic linear features increased with increasing density of these features on the landscape, while selection for natural linear features declined, indicating compensatory selection of anthropogenic linear features. These results have implications for woodland caribou conservation. Prey encounter rates between wolves and caribou seem to be strongly influenced by increasing linear feature densities. This behavioral mechanism–a compensatory functional response to anthropogenic linear feature density resulting in decreased use of natural travel corridors–has negative consequences for the viability of woodland caribou.
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Affiliation(s)
- Erica J. Newton
- Ontario Ministry of Natural Resources and Forestry, Wildlife Research and Monitoring Section, Trent University, DNA Building, Peterborough, ON, Canada
- * E-mail:
| | - Brent R. Patterson
- Ontario Ministry of Natural Resources and Forestry, Wildlife Research and Monitoring Section, Trent University, DNA Building, Peterborough, ON, Canada
| | - Morgan L. Anderson
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
| | - Arthur R. Rodgers
- Ontario Ministry of Natural Resources and Forestry, Centre for Northern Forest Ecosystem Research, Thunder Bay, ON, Canada
| | | | - John M. Fryxell
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
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Kittle AM, Bukombe JK, Sinclair ARE, Mduma SAR, Fryxell JM. Landscape-level movement patterns by lions in western Serengeti: comparing the influence of inter-specific competitors, habitat attributes and prey availability. MOVEMENT ECOLOGY 2016; 4:17. [PMID: 27375849 PMCID: PMC4929767 DOI: 10.1186/s40462-016-0082-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 05/17/2016] [Indexed: 05/09/2023]
Abstract
BACKGROUND Where apex predators move on the landscape influences ecosystem structure and function and is therefore key to effective landscape-level management and species-specific conservation. However the factors underlying predator distribution patterns within functional ecosystems are poorly understood. Predator movement should be sensitive to the spatial patterns of inter-specific competitors, spatial variation in prey density, and landscape attributes that increase individual prey vulnerability. We investigated the relative role of these fundamental factors on seasonal resource utilization by a globally endangered apex carnivore, the African lion (Panthera leo) in Tanzania's Serengeti National Park. Lion space use was represented by novel landscape-level, modified utilization distributions (termed "localized density distributions") created from telemetry relocations of individual lions from multiple neighbouring prides. Spatial patterns of inter-specific competitors were similarly determined from telemetry re-locations of spotted hyenas (Crocuta crocuta), this system's primary competitor for lions; prey distribution was derived from 18 months of detailed census data; and remote sensing data was used to represent relevant habitat attributes. RESULTS Lion space use was consistently influenced by landscape attributes that increase individual prey vulnerability to predation. Wet season activity, when available prey were scarce, was concentrated near embankments, which provide ambush opportunities, and dry season activity, when available prey were abundant, near remaining water sources where prey occurrence is predictable. Lion space use patterns were positively associated with areas of high prey biomass, but only in the prey abundant dry season. Finally, at the broad scale of this analysis, lion and hyena space use was positively correlated in the comparatively prey-rich dry season and unrelated in the wet season, suggesting lion movement was unconstrained by the spatial patterns of their main inter-specific competitors. CONCLUSIONS The availability of potential prey and vulnerability of that prey to predation both motivate lion movement decisions, with their relative importance apparently mediated by overall prey abundance. With practical and theoretical implications, these results suggest that while top carnivores are consistently cognizant of how landscape features influence individual prey vulnerability, they also adopt a flexible approach to range use by adjusting spatial behaviour according to fluctuations in local prey abundance.
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Affiliation(s)
- Andrew M. Kittle
- />Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1 Canada
- />Present address: The Wilderness &Wildlife Conservation Trust, 130 Reid Avenue, Colombo 04, Sri Lanka
| | - John K. Bukombe
- />Tazania Wildlife Research Institute, P.O. Box 661, Arusha, United Republic of Tanzania
| | - Anthony R. E. Sinclair
- />Tazania Wildlife Research Institute, P.O. Box 661, Arusha, United Republic of Tanzania
- />Biodiversity Research Centre, University of British Columbia, Vancouver, BC V6T 1Z4 Canada
| | - Simon A. R. Mduma
- />Tazania Wildlife Research Institute, P.O. Box 661, Arusha, United Republic of Tanzania
| | - John M. Fryxell
- />Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1 Canada
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