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Mella VSA, Cooper CE, Karr M, Krockenberger A, Madani G, Webb EB, Krockenberger MB. Hot climate, hot koalas: the role of weather, behaviour and disease on thermoregulation. CONSERVATION PHYSIOLOGY 2024; 12:coae032. [PMID: 38803425 PMCID: PMC11129715 DOI: 10.1093/conphys/coae032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 04/08/2024] [Accepted: 04/30/2024] [Indexed: 05/29/2024]
Abstract
Thermoregulation is critical for endotherms living in hot, dry conditions, and maintaining optimal core body temperature (Tb) in a changing climate is an increasingly challenging task for mammals. Koalas (Phascolarctos cinereus) have evolved physiological and behavioural strategies to maintain homeostasis and regulate their Tb but are thought to be vulnerable to prolonged heat. We investigated how weather, behaviour and disease influence Tb for wild, free-living koalas during summer in north-west New South Wales. We matched Tb with daily behavioural observations in an ageing population where chlamydial disease is prevalent. Each individual koala had similar Tb rhythms (average Tb = 36.4 ± 0.05°C), but male koalas had higher Tb amplitude and more pronounced daily rhythm than females. Disease disrupted the 24-hr circadian pattern of Tb. Koala Tb increased with ambient temperature (Ta). On the hottest day of the study (maximum Ta = 40.8°C), we recorded the highest (Tb = 40.8°C) but also the lowest (Tb = 32.4°C) Tb ever documented for wild koalas, suggesting that they are more heterothermic than previously recognized. This requires individuals to predict days of extreme Ta from overnight and early morning conditions, adjusting Tb regulation accordingly, and it has never been reported before for koalas. The large diel amplitude and low minimum Tb observed suggest that koalas at our study site are energetically and nutritionally compromised, likely due to their age. Behaviour (i.e. tree hugging and drinking water) was not effective in moderating Tb. These results indicate that Ta and koala Tb are strongly interconnected and reinforce the importance of climate projections for predicting the future persistence of koalas throughout their current distribution. Global climate models forecast that dry, hot weather will continue to escalate and drought events will increase in frequency, duration and severity. This is likely to push koalas and other arboreal folivores towards their thermal limit.
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Affiliation(s)
- Valentina S A Mella
- Sydney School of Veterinary Science, The University of Sydney, Sydney, New South Wales 2006, Australia
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Christine E Cooper
- School of Molecular and Life Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Madeline Karr
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Andrew Krockenberger
- Division of Research and Innovation, James Cook University, Cairns, Queensland 4878, Australia
| | - George Madani
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Elliot B Webb
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
- Department of Planning and Environment, Science, Economics and Insights Division, Parramatta, New South Wales 2150, Australia
| | - Mark B Krockenberger
- Sydney School of Veterinary Science, The University of Sydney, Sydney, New South Wales 2006, Australia
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2
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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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Brown KL, Ganswindt A, Steenkamp G, Tordiffe ASW. Responses to Reduced Feeding Frequency in Captive-Born Cheetahs ( Acinonyx jubatus): Implications for Behavioural and Physiological Stress and Gastrointestinal Health. Animals (Basel) 2023; 13:2783. [PMID: 37685047 PMCID: PMC10486355 DOI: 10.3390/ani13172783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/22/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023] Open
Abstract
Unnatural diet composition and frequent feeding regimes may play an aetiological role in the multiple diseases prevalent in captive cheetahs. This study investigated the responses of captive-born (hand-reared) cheetahs (n = 6) to a reduced feeding frequency schedule distinguished by offering larger quantities of food less frequently. The study cheetahs were fed four once-daily meals per week during the 3-week treatment period, followed by a 3-week control period in which they were fed two daily rations six days a week. Total weekly food intake was maintained throughout the study. Variations in behaviour, faecal consistency score (FCS), and faecal glucocorticoid metabolite concentration were measured. Less frequent feeding resulted in higher FCS (p < 0.01) and locomotory behaviour (p < 0.05) among the studied cheetahs. Faecal glucocorticoid metabolite concentration demonstrated an initial acute stress response to the change in feeding frequency (p < 0.05) and subsequent adaptation. The results of the FCS analysis suggest that the more natural feeding pattern could have benefited the studied cheetahs' gastrointestinal health without a significant behavioural or physiological stress response overall to the change in feeding frequency.
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Affiliation(s)
- Kelsey Lee Brown
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa
- Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa
| | - André Ganswindt
- Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, Mammal Research Institute, University of Pretoria, Pretoria 0028, South Africa
| | - Gerhard Steenkamp
- Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa
| | - Adrian Stephen Wolferstan Tordiffe
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa
- Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa
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4
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Blakey RV, Sikich JA, Blumstein DT, Riley SP. Mountain lions avoid burned areas and increase risky behavior after wildfire in a fragmented urban landscape. Curr Biol 2022; 32:4762-4768.e5. [DOI: 10.1016/j.cub.2022.08.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/13/2022] [Accepted: 08/31/2022] [Indexed: 11/09/2022]
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5
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Diurnal and Nocturnal Behaviour of Cheetahs (Acinonyx jubatus) and Lions (Panthera leo) in Zoos. Animals (Basel) 2022; 12:ani12182367. [PMID: 36139229 PMCID: PMC9495184 DOI: 10.3390/ani12182367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/30/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
Mammals are constantly exposed to exogenous and endogenous influences that affect their behaviour and daily activity. Light and temperature, as well as anthropogenic factors such as husbandry routines, visitors, and feeding schedules are potential influences on animals in zoological gardens. In order to investigate the effects of some of these factors on animal behaviour, observational studies based on the analyses of activity budgets can be used. In this study, the daily and nightly activity budgets of six lions (Panthera leo) and five cheetahs (Acinonyx jubatus) from four EAZA institutions were investigated. Focused on the influencing factor light and feeding, we analysed these activity budgets descriptively. Behaviour was recorded and analysed during the winter months over an observation period of 14 days and 14 nights using infrared-sensitive cameras. Our results show that lions and cheetahs exhibit activity peaks at crepuscular and feeding times, regardless of husbandry. Thus, lions in captivity shift nocturnal behaviour familiar from the wild to crepuscular and diurnal times. In cheetahs, in contrast, captive and wild individuals show similar 24 h behavioural rhythms. The resting behaviour of both species is more pronounced at night, with cheetahs having a shorter overall sleep duration than lions. This study describes the results of the examined animals and is not predictive. Nevertheless, the results of this study make an important contribution to gaining knowledge about possible factors influencing the behaviour of lions and cheetahs in zoos and offer implications that could be useful for improving husbandry and management.
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6
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Dynamic landscapes of fear: understanding spatiotemporal risk. Trends Ecol Evol 2022; 37:911-925. [PMID: 35817684 DOI: 10.1016/j.tree.2022.06.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 06/10/2022] [Accepted: 06/14/2022] [Indexed: 02/04/2023]
Abstract
The landscape of fear (LOF) concept posits that prey navigate spatial heterogeneity in perceived predation risk, balancing risk mitigation against other activities necessary for survival and reproduction. These proactive behavioral responses to risk can affect individual fitness, population dynamics, species interactions, and coexistence. Yet, antipredator responses in free-ranging prey often contradict expectations, raising questions about the generality and scalability of the LOF framework and suggesting that a purely spatial, static LOF conceptualization may be inadequate. Here, we outline a 'dynamic' LOF framework that explicitly incorporates time to account for predictable spatiotemporal variation in risk-resource trade-offs. This integrated approach suggests novel predictions about predator effects on prey behaviors to refine understanding of the role predators play in ecological communities.
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7
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Heat stress and sperm production in the domestic cat. Theriogenology 2022; 187:182-187. [DOI: 10.1016/j.theriogenology.2022.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/31/2022] [Accepted: 05/10/2022] [Indexed: 11/22/2022]
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Wild TA, Wikelski M, Tyndel S, Alarcón‐Nieto G, Klump BC, Aplin LM, Meboldt M, Williams HJ. Internet on animals: Wi‐Fi‐enabled devices provide a solution for big data transmission in biologging. Methods Ecol Evol 2022. [DOI: 10.1111/2041-210x.13798] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Timm A. Wild
- Department of Migration Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Product Development Group Zurich (pd z) ETH Zürich Zürich Switzerland
| | - Martin Wikelski
- Department of Migration Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
| | - Stephen Tyndel
- Cognitive and Cultural Ecology Research Group Max Planck Institute of Animal Behavior Radolfzell Germany
| | - Gustavo Alarcón‐Nieto
- Cognitive and Cultural Ecology Research Group Max Planck Institute of Animal Behavior Radolfzell Germany
| | - Barbara C. Klump
- Cognitive and Cultural Ecology Research Group Max Planck Institute of Animal Behavior Radolfzell Germany
| | - Lucy M. Aplin
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
- Cognitive and Cultural Ecology Research Group Max Planck Institute of Animal Behavior Radolfzell Germany
| | - Mirko Meboldt
- Product Development Group Zurich (pd z) ETH Zürich Zürich Switzerland
| | - Hannah J. Williams
- Department of Migration Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
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Wemer N, Naude VN, Merwe VC, Smit M, Lange G, Komdeur J. Successful predatory‐avoidance behaviour to lion auditory cues during soft‐release from captivity in cheetah. Ethology 2021. [DOI: 10.1111/eth.13261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nynke Wemer
- Behavioral Physiology and Ecology Group Groningen Institute for Evolutionary Life Sciences (GELIFES) University of Groningen Groningen the Netherlands
| | - Vincent N. Naude
- Institute for Communities and Wildlife in Africa University of Cape Town Rondebosch South Africa
| | - Vincent C. Merwe
- Institute for Communities and Wildlife in Africa University of Cape Town Rondebosch South Africa
- Endangered Wildlife Trust Johannesburg South Africa
| | - Marna Smit
- Ashia Cheetah Conservation Paarl South Africa
| | - Gerhard Lange
- Kuzuko Lodge Private Game Reserve Greater Addo Area South Africa
| | - Jan Komdeur
- Behavioral Physiology and Ecology Group Groningen Institute for Evolutionary Life Sciences (GELIFES) University of Groningen Groningen the Netherlands
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10
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Levesque DL, Nowack J, Boyles JG. Body Temperature Frequency Distributions: A Tool for Assessing Thermal Performance in Endotherms? Front Physiol 2021; 12:760797. [PMID: 34721082 PMCID: PMC8551754 DOI: 10.3389/fphys.2021.760797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 09/07/2021] [Indexed: 12/25/2022] Open
Abstract
There is increasing recognition that rather than being fully homeothermic, most endotherms display some degree of flexibility in body temperature. However, the degree to which this occurs varies widely from the relatively strict homeothermy in species, such as humans to the dramatic seasonal hibernation seen in Holarctic ground squirrels, to many points in between. To date, attempts to analyse this variability within the framework generated by the study of thermal performance curves have been lacking. We tested if frequency distribution histograms of continuous body temperature measurements could provide a useful analogue to a thermal performance curve in endotherms. We provide examples from mammals displaying a range of thermoregulatory phenotypes, break down continuous core body temperature traces into various components (active and rest phase modes, spreads and skew) and compare these components to hypothetical performance curves. We did not find analogous patterns to ectotherm thermal performance curves, in either full datasets or by breaking body temperature values into more biologically relevant components. Most species had either bimodal or right-skewed (or both) distributions for both active and rest phase body temperatures, indicating a greater capacity for mammals to tolerate body temperatures elevated above the optimal temperatures than commonly assumed. We suggest that while core body temperature distributions may prove useful in generating optimal body temperatures for thermal performance studies and in various ecological applications, they may not be a good means of assessing the shape and breath of thermal performance in endotherms. We also urge researchers to move beyond only using mean body temperatures and to embrace the full variability in both active and resting temperatures in endotherms.
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Affiliation(s)
- D L Levesque
- School of Biology and Ecology, University of Maine, Orono, ME, United States
| | - J Nowack
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - J G Boyles
- Cooperative Wildlife Research Laboratory, Center for Ecology, and School of Biological Sciences, Southern Illinois University, Carbondale, IL, United States
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Peterson M, Jorge MLSP, Jain A, Keuroghlian A, Oshima JEF, Richard-Hansen C, Berzins R, Ribeiro MC, Eaton D. Temperature induces activity reduction in a Neotropical ungulate. J Mammal 2021. [DOI: 10.1093/jmammal/gyab092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Because global climate change results in increasingly extreme temperatures and more frequent droughts, behavioral thermoregulation is one avenue by which species may adjust. Changes in activity patterns in response to temperature have been observed in a number of mammal species, but rarely have been investigated in humid tropical habitats. Here we examine the relationship between activity patterns and microclimate temperatures for white-lipped peccaries (Tayassu pecari, Tayassuidae, Cetartiodactyla) in four distinct biomes—the Cerrado, the Pantanal, the Atlantic Forest, and the Amazon. From 2013 to 2017, we monitored 30 white-lipped peccaries fitted with GPS collars that included accelerometers and temperature sensors. White-lipped peccaries were primarily diurnal, with peaks of activity in the morning and late afternoon, except in the Amazon where activity was high throughout the day. Total time active did not vary seasonally. White-lipped peccaries were significantly less likely to be active as temperatures increased, with the probability of being active decreasing by >49% in all biomes between 30 and 40°C. Our findings indicate that white-lipped peccaries are likely to be adversely impacted by rising temperatures, through being forced to reduce foraging time during their prime active periods.
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Affiliation(s)
- Michaela Peterson
- Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee 37235, USA
| | - Maria Luisa S P Jorge
- Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee 37235, USA
| | - Avarna Jain
- Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, Tennessee 37235, USA
| | | | - Júlia Emi F Oshima
- Programa de Pós-Graduação em Zoologia, Laboratório de Ecologia Espacial e Conservação—LEEC, Depto. de Ecologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Av. 24-A, 1515, 13506-900, Rio Claro, São Paulo, Brasil
| | - Cécile Richard-Hansen
- Office français de la Biodiversité (OFB), Kourou-Campus agronomique—French Guyana, France
- UMR EcoFog, Kourou-Campus agronomique—French Guiana, France
| | - Rachel Berzins
- Office français de la Biodiversité (OFB), Kourou-Campus agronomique—French Guyana, France
| | - Milton Cezar Ribeiro
- Programa de Pós-Graduação em Zoologia, Laboratório de Ecologia Espacial e Conservação—LEEC, Depto. de Ecologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Av. 24-A, 1515, 13506-900, Rio Claro, São Paulo, Brasil
| | - Don Eaton
- Peccary Project/IUCN/SSC Peccary Specialist Group, Campo Grande, Brazil
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Temporal partitioning and spatiotemporal avoidance among large carnivores in a human-impacted African landscape. PLoS One 2021; 16:e0256876. [PMID: 34506529 PMCID: PMC8432863 DOI: 10.1371/journal.pone.0256876] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 08/17/2021] [Indexed: 11/21/2022] Open
Abstract
Africa is home to some of the world’s most functionally diverse guilds of large carnivores. However, they are increasingly under threat from anthropogenic pressures that may exacerbate already intense intra-guild competition. Understanding the coexistence mechanisms employed by these species in human-impacted landscapes could help shed light on some of the more subtle ways in which humans may impact wildlife populations, and inform multi-species conservation planning. We used camera trap data from Tanzania’s Ruaha-Rungwa landscape to explore temporal and spatiotemporal associations between members of an intact East African large carnivore guild, and determine how these varied across gradients of anthropogenic impact and protection. All large carnivores except African wild dog (Lycaon pictus) exhibited predominantly nocturnal road-travel behaviour. Leopard (Panthera pardus) appeared to employ minor temporal avoidance of lion (Panthera leo) in all sites except those where human impacts were highest, suggesting that leopard may have been freed up from avoidance of lion in areas where the dominant competitor was less abundant, or that the need for leopard to avoid humans outweighed the need to avoid sympatric competitors. Lion appeared to modify their activity patterns to avoid humans in the most impacted areas. We also found evidence of avoidance and attraction among large carnivores: lion and spotted hyaena (Crocuta crocuta) followed leopard; leopard avoided lion; spotted hyaena followed lion; and lion avoided spotted hyaena. Our findings suggest that large carnivores in Ruaha-Rungwa employ fine-scale partitioning mechanisms to facilitate coexistence with both sympatric species and humans, and that growing human pressures may interfere with these behaviours.
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Using Machine Learning for Remote Behaviour Classification-Verifying Acceleration Data to Infer Feeding Events in Free-Ranging Cheetahs. SENSORS 2021; 21:s21165426. [PMID: 34450868 PMCID: PMC8398415 DOI: 10.3390/s21165426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/01/2021] [Accepted: 08/05/2021] [Indexed: 11/25/2022]
Abstract
Behavioural studies of elusive wildlife species are challenging but important when they are threatened and involved in human-wildlife conflicts. Accelerometers (ACCs) and supervised machine learning algorithms (MLAs) are valuable tools to remotely determine behaviours. Here we used five captive cheetahs in Namibia to test the applicability of ACC data in identifying six behaviours by using six MLAs on data we ground-truthed by direct observations. We included two ensemble learning approaches and a probability threshold to improve prediction accuracy. We used the model to then identify the behaviours in four free-ranging cheetah males. Feeding behaviours identified by the model and matched with corresponding GPS clusters were verified with previously identified kill sites in the field. The MLAs and the two ensemble learning approaches in the captive cheetahs achieved precision (recall) ranging from 80.1% to 100.0% (87.3% to 99.2%) for resting, walking and trotting/running behaviour, from 74.4% to 81.6% (54.8% and 82.4%) for feeding behaviour and from 0.0% to 97.1% (0.0% and 56.2%) for drinking and grooming behaviour. The model application to the ACC data of the free-ranging cheetahs successfully identified all nine kill sites and 17 of the 18 feeding events of the two brother groups. We demonstrated that our behavioural model reliably detects feeding events of free-ranging cheetahs. This has useful applications for the determination of cheetah kill sites and helping to mitigate human-cheetah conflicts.
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Tatler J, Currie SE, Cassey P, Scharf AK, Roshier DA, Prowse TAA. Accelerometer informed time-energy budgets reveal the importance of temperature to the activity of a wild, arid zone canid. MOVEMENT ECOLOGY 2021; 9:11. [PMID: 33736705 PMCID: PMC7977315 DOI: 10.1186/s40462-021-00246-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 02/21/2021] [Indexed: 06/01/2023]
Abstract
BACKGROUND Globally, arid regions are expanding and becoming hotter and drier with climate change. For medium and large bodied endotherms in the arid zone, the necessity to dissipate heat drives a range of adaptations, from behaviour to anatomy and physiology. Understanding how apex predators negotiate these landscapes and how they balance their energy is important as it may have broad impacts on ecosystem function. METHODS We used tri-axial accelerometry (ACC) and GPS data collected from free-ranging dingoes in central Australia to investigate their activity-specific energetics, and activity patterns through time and space. We classified dingo activity into stationary, walking, and running behaviours, and estimated daily energy expenditure via activity-specific time-energy budgets developed using energy expenditure data derived from the literature. We tested whether dingoes behaviourally thermoregulate by modelling ODBA as a function of ambient temperature during the day and night. We used traditional distance measurements (GPS) as well as fine-scale activity (ODBA) data to assess their daily movement patterns. RESULTS We retrieved ACC and GPS data from seven dingoes. Their mass-specific daily energy expenditure was significantly lower in summer (288 kJ kg- 1 day- 1) than winter (495 kJ kg- 1 day- 1; p = 0.03). Overall, dingoes were much less active during summer where 91% of their day was spent stationary in contrast to just 46% during winter. There was a sharp decrease in ODBA with increasing ambient temperature during the day (R2 = 0.59), whereas ODBA increased with increasing Ta at night (R2 = 0.39). Distance and ODBA were positively correlated (R = 0.65) and produced similar crepuscular patterns of activity. CONCLUSION Our results indicate that ambient temperature may drive the behaviour of dingoes. Seasonal differences of daily energy expenditure in free-ranging eutherian mammals have been found in several species, though this was the first time it has been observed in a wild canid. We conclude that the negative relationship between dingo activity (ODBA) and ambient temperature during the day implies that high heat gain from solar radiation may be a factor limiting diurnal dingo activity in an arid environment.
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Affiliation(s)
- Jack Tatler
- Invasion Science & Wildlife Ecology Lab, University of Adelaide, Adelaide, SA, 5005, Australia.
| | - Shannon E Currie
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke Str. 17, 10315, Berlin, Germany
| | - Phillip Cassey
- Invasion Science & Wildlife Ecology Lab, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Anne K Scharf
- Department of Migration, Max Planck Institute of Animal Behavior, Am Obstberg 1, 78315, Radolfzell, Germany
| | - David A Roshier
- Australian Wildlife Conservancy, PO Box 8070, Subiaco East, WA, 6008, Australia
| | - Thomas A A Prowse
- School of Mathematical Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
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15
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Fuller A, Mitchell D, Maloney SK, Hetem RS, Fonsêca VFC, Meyer LCR, van de Ven TMFN, Snelling EP. How dryland mammals will respond to climate change: the effects of body size, heat load and a lack of food and water. J Exp Biol 2021; 224:224/Suppl_1/jeb238113. [PMID: 33627465 DOI: 10.1242/jeb.238113] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Mammals in drylands are facing not only increasing heat loads but also reduced water and food availability as a result of climate change. Insufficient water results in suppression of evaporative cooling and therefore increases in body core temperature on hot days, while lack of food reduces the capacity to maintain body core temperature on cold nights. Both food and water shortage will narrow the prescriptive zone, the ambient temperature range over which body core temperature is held relatively constant, which will lead to increased risk of physiological malfunction and death. Behavioural modifications, such as shifting activity between night and day or seeking thermally buffered microclimates, may allow individuals to remain within the prescriptive zone, but can incur costs, such as reduced foraging or increased competition or predation, with consequences for fitness. Body size will play a major role in predicting response patterns, but identifying all the factors that will contribute to how well dryland mammals facing water and food shortage will cope with increasing heat loads requires a better understanding of the sensitivities and responses of mammals exposed to the direct and indirect effects of climate change.
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Affiliation(s)
- Andrea Fuller
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa .,Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa.,Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
| | - Duncan Mitchell
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa.,School of Human Sciences, Faculty of Science, University of Western Australia, Crawley 6009, WA, Australia
| | - Shane K Maloney
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa.,School of Human Sciences, Faculty of Science, University of Western Australia, Crawley 6009, WA, Australia
| | - Robyn S Hetem
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa.,School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg 2000, South Africa
| | - Vinicius F C Fonsêca
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa.,Innovation Group of Biometeorology and Animal Welfare (INOBIO-MANERA), Universidade Federal da Paraíba, Areia, 58397000, Brazil
| | - Leith C R Meyer
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa.,Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa.,Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
| | - Tanja M F N van de Ven
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa
| | - Edward P Snelling
- Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa.,Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa.,Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
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16
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Halsey LG, Bryce CM. Are humans evolved specialists for running in the heat? Man
vs
. horse races provide empirical insights. Exp Physiol 2020; 106:258-268. [DOI: 10.1113/ep088502] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 06/23/2020] [Indexed: 11/08/2022]
Affiliation(s)
- Lewis G. Halsey
- Department of Life Sciences University of Roehampton London SW15 4JD UK
| | - Caleb M. Bryce
- Botswana Predator Conservation Trust Private Bag 13 Maun Botswana
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17
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Owen‐Smith N, Hopcraft G, Morrison T, Chamaillé‐Jammes S, Hetem R, Bennitt E, Van Langevelde F. Movement ecology of large herbivores in African savannas: current knowledge and gaps. Mamm Rev 2020. [DOI: 10.1111/mam.12193] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Norman Owen‐Smith
- Centre for African Ecology School of Animal, Plant and Environmental Sciences University of the Witwatersrand Wits 2050 South Africa
| | - Grant Hopcraft
- Institute of Biodiversity, Animal Health and Comparative Medicine University of Glasgow Glasgow G12 8QQ UK
| | - Thomas Morrison
- Institute of Biodiversity, Animal Health and Comparative Medicine University of Glasgow Glasgow G12 8QQ UK
| | | | - Robyn Hetem
- School of Animal, Plant and Environmental Sciences University of the Witwatersrand Wits 2050 South Africa
| | - Emily Bennitt
- Okavango Research Institute University of Botswana Maun Botswana
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18
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Le Maho Y, Holyoak M. Symposium "How to track wild animals without disturbance and subsequent bias". Integr Zool 2018; 14:2-3. [PMID: 30589230 DOI: 10.1111/1749-4877.12377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Yvon Le Maho
- Institut Pluridisciplinaire Hubert Curien Strasbourg, France
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19
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Illing B. Cheetahs cannot fool biologgers. CONSERVATION PHYSIOLOGY 2018; 6:coy063. [PMID: 30591837 PMCID: PMC6301285 DOI: 10.1093/conphys/coy063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Indexed: 06/09/2023]
Affiliation(s)
- Björn Illing
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
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