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Marneweck CJ, Allen BL, Butler AR, Do Linh San E, Harris SN, Jensen AJ, Saldo EA, Somers MJ, Titus K, Muthersbaugh M, Vanak A, Jachowski DS. Middle‐out ecology: small carnivores as sentinels of global change. Mamm Rev 2022. [DOI: 10.1111/mam.12300] [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]
Affiliation(s)
- Courtney J. Marneweck
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Benjamin L. Allen
- Institute for Life Sciences and the Environment University of Southern Queensland Toowoomba QLD 4350 Australia
- Centre for African Conservation Ecology Nelson Mandela University Port Elizabeth 6034 South Africa
| | - Andrew R. Butler
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Emmanuel Do Linh San
- Department of Zoology and Entomology University of Fort Hare Alice 5700 South Africa
| | - Stephen N. Harris
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Alex J. Jensen
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Elizabeth A. Saldo
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Michael J. Somers
- Mammal Research Institute, Centre for Invasion Biology, Department of Zoology and Entomology University of Pretoria Pretoria 0002 South Africa
| | - Keifer Titus
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Michael Muthersbaugh
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
| | - Abi Vanak
- Ashoka Trust for Research in Ecology and the Environment Bengaluru 560064 India
- School of Life Sciences University of KwaZulu‐Natal 3629 South Africa
| | - David S. Jachowski
- Department of Forestry and Environmental Conservation Clemson University Clemson SC 29634 USA
- School of Life Sciences University of KwaZulu‐Natal 3629 South Africa
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2
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Ruperto EF, Taraborelli PA, Menéndez J, Sassi PL. Behavioral plasticity in two endemic rodents from the Andes Mountains: strategies for thermal and energetic balance. Mamm Biol 2022. [DOI: 10.1007/s42991-022-00263-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Effect of sex, age, and reproductive status on daily activity levels and activity patterns in jaguars (Panthera onca). MAMMAL RES 2021. [DOI: 10.1007/s13364-021-00589-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractAll animals, including carnivores, adapt their daily activity duration and distribution to satisfy food demands, breed, or avoid mortality risk. We used the kernel density method to estimate daily movement activity levels and movement activity patterns of jaguars in Hato Piñero, in Venezuelan Western Llanos, based on 3,656 jaguar detection time records from two and a half years of camera trapping. Jaguars were active for 11.7 h per day on average and exhibited mostly nocturnal and crepuscular activity pattern, however, with marked differences between sex/age/reproductive groups. Reproductive females had the highest daily activity level (13.2 h/day), followed by adult males (10.9 h/day), non-reproductive females (10.5 h/day), and cubs (8.7 h/day). Activity patterns also differed, with males and reproductive females having activity peaks at the same hours after sunset and before sunrise, cubs in the night and after sunrise, while non-reproductive females were most active during night hours. This study was the first to document the effect of sex, age, and reproductive status on daily level and activity pattern in the jaguar.
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Ohrnberger SA, Hambly C, Speakman JR, Valencak TG. Limits to sustained energy intake. XXXII. Hot again: dorsal shaving increases energy intake and milk output in golden hamsters ( Mesocricetus auratus). J Exp Biol 2020; 223:jeb230383. [PMID: 33188060 DOI: 10.1242/jeb.230383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 11/09/2020] [Indexed: 12/16/2022]
Abstract
Golden hamsters have four times the body size of mice, raise very large litters and are required to produce large quantities of milk during the 18-day lactation period. We have previously proposed that they may be prone to being limited by their heat dissipation capacity. Studies where lactating females are shaved to elevate their heat dissipation capacity have yielded conflicting data so far. With their short pregnancy of ∼18 days, the large litters and the reported high skin temperatures, they may serve as an ideal model to elucidate the role of epilation for energy budgets in lactating mammals. We shaved one group of lactating females dorsally on the sixth day of lactation, and tested if the elevated heat dissipation capacity would enable them to have higher energy intakes and better food-to-milk conversion rates. Indeed, we observed that females from the shaved group had 6% higher body mass and 0.78°C lower skin temperature than control females during lactation. When focusing on the phase of peak lactation, we observed significantly higher (10%) gross energy intake of food and 23.4% more milk energy output in the shaved females, resulting in 3.3 g higher individual pup weights. We conclude that shaving off the females' fur, even though restricted to the dorsal surface, had large consequences on female energy metabolism in lactation and improved milk production and pup growth in line with our previous work on heat dissipation limitation. Our new data from golden hamsters confirm heat dissipation as a limiting factor for sustained metabolic rate in lactation in some small mammals and emphasise the large effects of a relatively small manipulation such as fur removal on energy metabolism of lactating females.
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Affiliation(s)
- S A Ohrnberger
- Institute of Physiology, Pathophysiology and Biophysics, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
| | - C Hambly
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
| | - J R Speakman
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
- Institute of Genetics and Developmental Biology, State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
- CAS Center of Excellence in Animal Evolution and Genetics, Kunming 650223, China
| | - T G Valencak
- Institute of Physiology, Pathophysiology and Biophysics, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria
- College of Animal Sciences, Zhejiang University, Zijingang Campus, 866 Yuhangtang Road, 310058 Hangzhou, People's Republic of China
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Melville HIAS, Conway WC, Hardin JB, Comer CE, Morrison ML. Abiotic variables influencing the nocturnal movements of bobcats and coyotes. WILDLIFE BIOLOGY 2020. [DOI: 10.2981/wlb.00601] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Haemish I. A. S. Melville
- H. I. A. S. Melville (https://orcid.org/0000-0003-3331-2273) ✉ , Nature Conservation Programme, Dept of Environmental Sciences, UNISA Science Campus, Florida, Gauteng 1710, South Africa
| | - Warren C. Conway
- W. C. Conway, Bricker Endowed Chair in Wildlife Management, Dept of Natural Resources Management, Texas Tech Univ., Lubbock, TX, USA
| | - Jason B. Hardin
- J. B. Hardin, Turkey Program Leader, Texas Parks and Wildlife, Austin, TX, USA
| | - Christopher E. Comer
- C. E. Comer (https://orcid.org/0000-0002-8207-7444), Director of Conservation, Safari Club International Foundation, Tucson, AZ, USA
| | - Michael L. Morrison
- M. L. Morrison, Caesar Kleberg Chair, Dept of Rangeland, Wildlife and Fisheries Management, Texas A&M Univ., College Station, TX, USA
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Mos J, Hofmeester TR. The Mostela: an adjusted camera trapping device as a promising non-invasive tool to study and monitor small mustelids. MAMMAL RES 2020. [DOI: 10.1007/s13364-020-00513-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
AbstractIn spite of their potential important role in shaping small mammal population dynamics, weasel (Mustela nivalis) and stoat (Mustela erminea) are understudied due to the difficulty of detecting these species. Furthermore, their conservation status in many countries is unknown due to lack of monitoring techniques. There is thus an important need for a method to detect these small mustelids. In this study, we tested the efficiency of a recently developed camera trapping device, the Mostela, as a new technique to detect mustelids in a study area near Dieren, the Netherlands. We placed Mostelas in linear landscape features, and other microhabitats thought to be frequently visited by weasels, from March to October 2017 and February to October 2018. We tested for yearly and monthly differences in site use and detectability, as well as the effect of entrance tube size, using an occupancy modelling framework. We found large seasonal differences in site use and detectability of weasels with the highest site use in June to October and highest detection probability in August and September. Detection probability was approximately two times higher for Mostelas with a 10-cm entrance tube compared with 8-cm. Furthermore, we were able to estimate activity patterns based on the time of detection, identify the sex in most detections (69.5%), and distinguish several individuals. Concluding, the Mostela seems promising as a non-invasive monitoring tool to study the occurrence and ecology of small mustelids. Further development of individual recognition from images would enable using the Mostela for density estimates applying capture-recapture models.
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Tapper S, Nocera JJ, Burness G. Heat dissipation capacity influences reproductive performance in an aerial insectivore. J Exp Biol 2020; 223:jeb222232. [PMID: 32321750 DOI: 10.1242/jeb.222232] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/08/2020] [Indexed: 12/26/2022]
Abstract
Climatic warming is predicted to increase the frequency of extreme weather events, which may reduce an individual's capacity for sustained activity because of thermal limits. We tested whether the risk of overheating may limit parental provisioning of an aerial insectivorous bird in population decline. For many seasonally breeding birds, parents are thought to operate close to an energetic ceiling during the 2-3 week chick-rearing period. The factors determining the ceiling remain unknown, although it may be set by an individual's capacity to dissipate body heat (the heat dissipation limitation hypothesis). Over two breeding seasons we experimentally trimmed the ventral feathers of female tree swallows (Tachycineta bicolor) to provide a thermal window. We then monitored maternal and paternal provisioning rates, nestling growth rates and fledging success. We found the effect of our experimental treatment was context dependent. Females with an enhanced capacity to dissipate heat fed their nestlings at higher rates than controls when conditions were hot, but the reverse was true under cool conditions. Control females and their mates both reduced foraging under hot conditions. In contrast, male partners of trimmed females maintained a constant feeding rate across temperatures, suggesting attempts to match the feeding rate of their partners. On average, nestlings of trimmed females were heavier than controls, but did not have a higher probability of fledging. We suggest that removal of a thermal constraint allowed females to increase provisioning rates, but additionally provided nestlings with a thermal advantage via increased heat transfer during maternal brooding. Our data provide support for the heat dissipation limitation hypothesis and suggest that depending on temperature, heat dissipation capacity can influence reproductive success in aerial insectivores.
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Affiliation(s)
- Simon Tapper
- Environmental and Life Sciences Graduate Program, Trent University, 1600 West Bank Drive, Peterborough, ON, Canada, K9L 0G2
| | - Joseph J Nocera
- University of New Brunswick, Forestry and Environmental Management, Fredericton, NB, Canada, E3B 5A3
| | - Gary Burness
- Department of Biology, Trent University, Trent University, 1600 West Bank Drive, Peterborough, ON, Canada, K9L 0G2
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Andreasson F, Hegemann A, Nord A, Nilsson JÅ. Experimental facilitation of heat loss affects work rate and innate immune function in a breeding passerine bird. J Exp Biol 2020; 223:jeb.219790. [DOI: 10.1242/jeb.219790] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 03/11/2020] [Indexed: 01/06/2023]
Abstract
The capacity to get rid of excess heat produced during hard work is a possible constraint on parental effort during reproduction (heat dissipation limit [HDL] theory). We released hard-working blue tits (Cyanistes caeruleus) from this constraint by experimentally removing ventral plumage. We then assessed if this changed their reproductive effort (feeding rate and nestling size) and levels of self-maintenance (change in body mass and innate immune function). Feather-clipped females reduced the number of feeding visits and increased levels of constitutive innate immunity compared to unclipped females but did not fledge smaller nestlings. Thus, they increased self-maintenance without compromising current reproductive output. In contrast, feather-clipping did not affect the number of feeding visits or innate immune function in males, despite increased heat loss rate. Our results show that analyses of physiological parameters, such as constitutive innate immune function, can be important when trying to understand sources of variation in investment in self-maintenance versus reproductive effort and that risk of overheating can influence innate immune function during reproduction.
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Affiliation(s)
- Fredrik Andreasson
- Department of Biology, Section for Evolutionary Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
| | - Arne Hegemann
- Department of Biology, Section for Evolutionary Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
| | - Andreas Nord
- Department of Biology, Section for Evolutionary Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
- Scottish Centre for Ecology and the Natural Environment, Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Rowardennan G63 0AW, UK
| | - Jan-Åke Nilsson
- Department of Biology, Section for Evolutionary Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden
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Rosenbaum B, Reading RP, Tsogtjargal G, Amgalanbaatar S, Comte S. Seasonal variation in the foraging activity of desert argali (Ovis ammon) in Mongolia. CAN J ZOOL 2019. [DOI: 10.1139/cjz-2018-0239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Debate remains whether energy maximization or time minimization strategies best explain foraging in ungulates. It has also been hypothesized that the capacity of an animal to dissipate body heat regulates animal activity. We investigated these hypotheses while measuring the daily activity of desert argali (Ovis ammon (Linnaeus,1758)) for 12 months and relating the activity pattern to environmental seasonality. We found significant seasonal cycles in argali activity, with the greatest proportion of daytime in winter spent foraging and the greatest proportion of daytime in summer spent bedding. Consistent with an energy maximization strategy, argali reduced all behaviors during the winter in favor of foraging, compensating for the increased energy demands of winter at a time of low forage quality. Consistent with a time minimization strategy, argali in summer significantly reduced foraging and spent more time bedding in shaded areas to avoid hyperthermia due to high ambient temperatures. Both optimal foraging and heat dissipation can be used to explain the observed foraging pattern. Foraging behavior in argali is best described by the extent to which the animals schedule their activities to meet their physiological demands, the way these demands are affected by environmental variables, and the time that is available to accomplish them.
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Affiliation(s)
- Barry Rosenbaum
- Denver Zoological Foundation, 2300 Steele Street, Denver, CO 80205, USA
| | - Richard P. Reading
- Butterfly Pavilion, 6252 West 104th Avenue, Westminster, CO 80020, USA; Coalition for International Conservation, Denver, CO 80220, USA
| | - Garam Tsogtjargal
- Mongolian Academy of Sciences, Mammalian Ecology Laboratory, Institute of General and Experimental Biology, Bayanzurkh District, 54b Peace Avenue, Ulaanbaatar 210351, Mongolia
| | - Sukh Amgalanbaatar
- Ulaanbaatar State University, 13343 Peace Avenue, Luvsantseveen’s Street, 5th khoroo, 15th khoroolol, Bayanzurkh District, PO-51, Box-167, Ulaanbaatar 210351, Mongolia
| | - Sebastien Comte
- School of Natural Sciences, College of Science and Engineering, University of Tasmania, Private Bag 55, Hobart TAS 7001, Australia
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Nilsson JÅ, Nord A. Testing the heat dissipation limit theory in a breeding passerine. Proc Biol Sci 2019; 285:rspb.2018.0652. [PMID: 29769365 DOI: 10.1098/rspb.2018.0652] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 04/19/2018] [Indexed: 11/12/2022] Open
Abstract
The maximum work rate of animals has recently been suggested to be determined by the rate at which excess metabolic heat generated during work can be dissipated (heat dissipation limitation (HDL) theory). As a first step towards testing this theory in wild animals, we experimentally manipulated brood size in breeding marsh tits (Poecile palustris) to change their work rate. Parents feeding nestlings generally operated at above-normal body temperatures. Body temperature in both males and females increased with maximum ambient temperature and with manipulated work rate, sometimes even exceeding 45°C, which is close to suggested lethal levels for birds. Such high body temperatures have previously only been described for birds living in hot and arid regions. Thus, reproductive effort in marsh tits may potentially be limited by the rate of heat dissipation. Females had lower body temperatures, a possible consequence of their brood patch serving as a thermal window facilitating heat dissipation. Because increasing body temperatures are connected to somatic costs, we suggest that the HDL theory may constitute a possible mediator of the trade-off between current and future reproduction. It follows that globally increasing, more stochastic, ambient temperatures may restrict the capacity for sustained work of animals in the future.
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Affiliation(s)
- Jan-Åke Nilsson
- Department of Biology, Section of Evolutionary Ecology, Lund University, Ecology Building, 223 62 Lund, Sweden
| | - Andreas Nord
- Department of Biology, Section of Evolutionary Ecology, Lund University, Ecology Building, 223 62 Lund, Sweden
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11
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Affiliation(s)
- Andreas Nord
- Department of Biology, Section for Evolutionary Ecology, Ecology Building Lund University Lund Sweden
| | - Jan‐Åke Nilsson
- Department of Biology, Section for Evolutionary Ecology, Ecology Building Lund University Lund Sweden
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12
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Caravaggi A, Gatta M, Vallely MC, Hogg K, Freeman M, Fadaei E, Dick JT, Montgomery WI, Reid N, Tosh DG. Seasonal and predator-prey effects on circadian activity of free-ranging mammals revealed by camera traps. PeerJ 2018; 6:e5827. [PMID: 30498626 PMCID: PMC6252065 DOI: 10.7717/peerj.5827] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 09/25/2018] [Indexed: 11/20/2022] Open
Abstract
Endogenous circadian and seasonal activity patterns are adapted to facilitate effective utilisation of environmental resources. Activity patterns are shaped by physiological constraints, evolutionary history, circadian and seasonal changes and may be influenced by other factors, including ecological competition and interspecific interactions. Remote-sensing camera traps allow the collection of species presence data throughout the 24 h period and for almost indefinite lengths of time. Here, we collate data from 10 separate camera trap surveys in order to describe circadian and seasonal activity patterns of 10 mammal species, and, in particular, to evaluate interspecific (dis)associations of five predator-prey pairs. We recorded 8,761 independent detections throughout Northern Ireland. Badgers, foxes, pine martens and wood mice were nocturnal; European and Irish hares and European rabbits were crepuscular; fallow deer and grey and red squirrels were diurnal. All species exhibited significant seasonal variation in activity relative to the timing of sunrise/sunset. Foxes in particular were more crepuscular from spring to autumn and hares more diurnal. Lagged regression analyses of predator-prey activity patterns between foxes and prey (hares, rabbits and wood mice), and pine marten and prey (squirrel and wood mice) revealed significant annual and seasonal cross-correlations. We found synchronised activity patterns between foxes and hares, rabbits and wood mice and pine marten and wood mice, and asynchrony between squirrels and pine martens. Here, we provide fundamental ecological data on endemic, invasive, pest and commercially valuable species in Ireland, as well as those of conservation importance and those that could harbour diseases of economic and/or zoonotic relevance. Our data will be valuable in informing the development of appropriate species-specific methodologies and processes and associated policies.
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Affiliation(s)
- Anthony Caravaggi
- School of Biological Sciences, Queen’s University Belfast, UK
- School of Biological Earth and Environmental Sciences, University College Cork, Cork, Ireland
| | - Maria Gatta
- School or Animal, Plant and Environmental Sciences, University of Witwatersrand, South Africa
| | - Marie-Claire Vallely
- School of Biological Sciences, Queen’s University Belfast, UK
- Northern Ireland Environment Agency, UK
| | - Kayleigh Hogg
- School of Biological Sciences, Queen’s University Belfast, UK
| | | | - Erfan Fadaei
- School of Biological Sciences, Queen’s University Belfast, UK
- Institute of Global Food Security (IGFS), Queen’s University Belfast, UK
| | - Jaimie T.A. Dick
- School of Biological Sciences, Queen’s University Belfast, UK
- Institute of Global Food Security (IGFS), Queen’s University Belfast, UK
| | - W. Ian Montgomery
- School of Biological Sciences, Queen’s University Belfast, UK
- Institute of Global Food Security (IGFS), Queen’s University Belfast, UK
| | - Neil Reid
- School of Biological Sciences, Queen’s University Belfast, UK
- Institute of Global Food Security (IGFS), Queen’s University Belfast, UK
| | - David G. Tosh
- School of Biological Sciences, Queen’s University Belfast, UK
- National Museums Northern Ireland, UK
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Atmeh K, Andruszkiewicz A, Zub K. Climate change is affecting mortality of weasels due to camouflage mismatch. Sci Rep 2018; 8:7648. [PMID: 29795400 PMCID: PMC5967304 DOI: 10.1038/s41598-018-26057-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/02/2018] [Indexed: 11/09/2022] Open
Abstract
Direct phenological mismatch caused by climate change can occur in mammals that moult seasonally. Two colour morphs of the weasel Mustela nivalis (M. n.) occur sympatrically in Białowieża Forest (NE Poland) and differ in their winter pelage colour: white in M. n. nivalis and brown in M. n. vulgaris. Due to their small body size, weasels are vulnerable to attacks by a range of different predators; thus cryptic coat colour may increase their winter survival. By analysing trapping data, we found that the share of white subspecies in the weasel population inhabiting Białowieża Forest decreases with decreasing numbers of days with snow cover. This led us to hypothesise that selective predation pressure should favour one of the two phenotypes, according to the prevailing weather conditions in winter. A simple field experiment with weasel models (white and brown), exposed against different background colours, revealed that contrasting models faced significantly higher detection by predators. Our observations also confirmed earlier findings that the plasticity of moult in M. n. nivalis is very limited. This means that climate change will strongly influence the mortality of the nivalis-type due to prolonged camouflage mismatch, which will directly affect the abundance and geographical distribution of this subspecies.
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Affiliation(s)
- Kamal Atmeh
- Université de Bordeaux, 351 Cours de la Libération, 33400, Talence, France.,Univ Lyon, Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR5558, F-69622, Villeurbanne, France
| | - Anna Andruszkiewicz
- Mammal Research Institute of the Polish Academy of Sciences, Stoczek 1, 17-230, Białowieża, Poland
| | - Karol Zub
- Mammal Research Institute of the Polish Academy of Sciences, Stoczek 1, 17-230, Białowieża, Poland.
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14
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Seasonal changes in energy expenditure, body temperature and activity patterns in llamas (Lama glama). Sci Rep 2017; 7:7600. [PMID: 28790450 PMCID: PMC5548813 DOI: 10.1038/s41598-017-07946-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/05/2017] [Indexed: 11/08/2022] Open
Abstract
Mammals typically keep their body temperature (Tb) within a narrow limit with changing environmental conditions. There are indications that some wild ungulates can exhibit certain forms of energy saving mechanisms when ambient temperatures are low and/or food is scarce. Therefore, the aim of the study was to determine if the llama, one of the most extensively kept domestic livestock species, exhibits seasonal adjustment mechanisms in terms of energy expenditure, Tb and locomotion. For that purpose llamas (N = 7) were kept in a temperate habitat on pasture. Locomotor activity, Tb (measured in the rumen) and the location of each animal were recorded continuously for one year using a telemetry system. Daily energy expenditure was measured as field metabolic rate (FMR). FMR fluctuated considerably between seasons with the lowest values found in winter (17.48 ± 3.98 MJ d−1, 402 kJ kg−0.75 d−1) and the highest in summer (25.87 ± 3.88 MJ d−1, 586 kJ kg−0.75 d−1). Llamas adjusted their energy expenditure, Tb and locomotor activity according to season and also time of day. Thus, llamas seem to have maintained the ability to reduce their energy expenditure and adjust their Tb under adverse environmental conditions as has been reported for some wild ungulates.
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15
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Levesque DL, Nowack J, Stawski C. Modelling mammalian energetics: the heterothermy problem. ACTA ACUST UNITED AC 2016. [DOI: 10.1186/s40665-016-0022-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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16
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Rezende EL, Bacigalupe LD. Thermoregulation in endotherms: physiological principles and ecological consequences. J Comp Physiol B 2015; 185:709-27. [PMID: 26025431 DOI: 10.1007/s00360-015-0909-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 04/18/2015] [Accepted: 04/27/2015] [Indexed: 01/01/2023]
Abstract
In a seminal study published nearly 70 years ago, Scholander et al. (Biol Bull 99:259-271, 1950) employed Newton's law of cooling to describe how metabolic rates (MR) in birds and mammals vary predictably with ambient temperature (T a). Here, we explore the theoretical consequences of Newton's law of cooling and show that a thermoregulatory polygon provides an intuitively simple and yet useful description of thermoregulatory responses in endothermic organisms. This polygon encapsulates the region in which heat production and dissipation are in equilibrium and, therefore, the range of conditions in which thermoregulation is possible. Whereas the typical U-shaped curve describes the relationship between T a and MR at rest, thermoregulatory polygons expand this framework to incorporate the impact of activity, other behaviors and environmental conditions on thermoregulation and energy balance. We discuss how this framework can be employed to study the limits to effective thermoregulation and their ecological repercussions, allometric effects and residual variation in MR and thermal insulation, and how thermoregulatory requirements might constrain locomotor or reproductive performance (as proposed, for instance, by the heat dissipation limit theory). In many systems the limited empirical knowledge on how organismal traits may respond to environmental changes prevents physiological ecology from becoming a fully developed predictive science. In endotherms, however, we contend that the lack of theoretical developments that translate current physiological understanding into formal mechanistic models remains the main impediment to study the ecological and evolutionary repercussions of thermoregulation. In spite of the inherent limitations of Newton's law of cooling as an oversimplified description of the mechanics of heat transfer, we argue that understanding how systems that obey this approximation work can be enlightening on conceptual grounds and relevant as an analytical and predictive tool to study ecological phenomena. As such, the proposed approach may constitute a powerful tool to study the impact of thermoregulatory constraints on variables related to fitness, such as survival and reproductive output, and help elucidating how species will be affected by ongoing climate change.
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Affiliation(s)
- Enrico L Rezende
- Department of Life Sciences, University of Roehampton, Holybourne Avenue, London, SW15 4JD, UK.
| | - Leonardo D Bacigalupe
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile.
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17
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White CR, Kearney MR. Metabolic scaling in animals: methods, empirical results, and theoretical explanations. Compr Physiol 2014; 4:231-56. [PMID: 24692144 DOI: 10.1002/cphy.c110049] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Life on earth spans a size range of around 21 orders of magnitude across species and can span a range of more than 6 orders of magnitude within species of animal. The effect of size on physiology is, therefore, enormous and is typically expressed by how physiological phenomena scale with mass(b). When b ≠ 1 a trait does not vary in direct proportion to mass and is said to scale allometrically. The study of allometric scaling goes back to at least the time of Galileo Galilei, and published scaling relationships are now available for hundreds of traits. Here, the methods of scaling analysis are reviewed, using examples for a range of traits with an emphasis on those related to metabolism in animals. Where necessary, new relationships have been generated from published data using modern phylogenetically informed techniques. During recent decades one of the most controversial scaling relationships has been that between metabolic rate and body mass and a number of explanations have been proposed for the scaling of this trait. Examples of these mechanistic explanations for metabolic scaling are reviewed, and suggestions made for comparing between them. Finally, the conceptual links between metabolic scaling and ecological patterns are examined, emphasizing the distinction between (1) the hypothesis that size- and temperature-dependent variation among species and individuals in metabolic rate influences ecological processes at levels of organization from individuals to the biosphere and (2) mechanistic explanations for metabolic rate that may explain the size- and temperature-dependence of this trait.
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Affiliation(s)
- Craig R White
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia
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Brinkmann L, Gerken M, Hambly C, Speakman JR, Riek A. Saving energy during hard times: energetic adaptations of Shetland pony mares. ACTA ACUST UNITED AC 2014; 217:4320-7. [PMID: 25359931 DOI: 10.1242/jeb.111815] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Recent results suggest that wild Northern herbivores reduce their metabolism during times of low ambient temperature and food shortage in order to reduce their energetic needs. It is, however, not known whether domesticated animals are also able to reduce their energy expenditure. We exposed 10 Shetland pony mares to different environmental conditions (summer and winter) and to two food quantities (60% and 100% of maintenance energy requirement) during low winter temperatures to examine energetic and behavioural responses. In summer, ponies showed a considerably higher field metabolic rate (FMR; 63.4±15.0 MJ day(-1)) compared with food-restricted and control animals in winter (24.6±7.8 and 15.0±1.1 MJ day(-1), respectively). During summer, locomotor activity, resting heart rate and total water turnover were considerably elevated (P<0.001) compared with winter. Animals on a restricted diet (N=5) compensated for the decreased energy supply by reducing their FMR by 26% compared with control animals (N=5). Furthermore, resting heart rate, body mass and body condition score were lower (29.2±2.7 beats min(-1), 140±22 kg and 3.0±1.0 points, respectively) than in control animals (36.8±41 beats min(-1), 165±31 kg, 4.4±0.7 points; P<0.05). While the observed behaviour did not change, nocturnal hypothermia was elevated. We conclude that ponies acclimatize to different climatic conditions by changing their metabolic rate, behaviour and some physiological parameters. When exposed to energy challenges, ponies, like wild herbivores, exhibited hypometabolism and nocturnal hypothermia.
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Affiliation(s)
- Lea Brinkmann
- Department of Animal Sciences, University of Göttingen, D-37075 Göttingen, Germany
| | - Martina Gerken
- Department of Animal Sciences, University of Göttingen, D-37075 Göttingen, Germany
| | - Catherine Hambly
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
| | - John R Speakman
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK. Institute of Genetics and Developmental Biology, State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, PR China
| | - Alexander Riek
- Department of Animal Sciences, University of Göttingen, D-37075 Göttingen, Germany.
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