Show simple item record

dc.contributor.authorDi Bernardi, Cecilia
dc.contributor.authorThierry, Anne-Mathilde
dc.contributor.authorEide, Nina Elisabeth
dc.contributor.authorBowler, Diana Elizabeth
dc.contributor.authorRød-Eriksen, Lars
dc.contributor.authorBlumentrath, Stefan
dc.contributor.authorTietgen, Lukas
dc.contributor.authorSandercock, Brett
dc.contributor.authorFlagstad, Øystein
dc.contributor.authorLanda, Arild
dc.description.abstract1. Selection for crypsis has been recognized as an important ecological driver of animal colouration, whereas the relative importance of thermoregulation is more contentious with mixed empirical support. A potential thermal advantage of darker individuals has been observed in a wide range of animal species. Arctic animals that exhibit colour polymorphisms and undergo seasonal colour moults are interesting study subjects for testing the two alternative hypotheses: demographic performance of different colour morphs might be differentially affected by snow cover with a cryptic advantage for lighter morphs, or conversely by winter temperature with a thermal advantage for darker morphs. 2. In this study, we explored whether camouflage and thermoregulation might explain differences in reproduction and survival between the white and blue colour morphs of the Arctic fox Vulpes lagopus under natural conditions. 3. Juvenile and adult survival, breeding propensity and litter size were measured for 798 captive-bred and released or wild-born Arctic foxes monitored during an 11-year period (2007–2017) in two subpopulations in south-central Norway. We investigated the proportion of the two colour morphs and compared their demographic performance in relation to spatial variation in duration of snow cover, onset of snow season and winter temperatures. 4. After population re-establishment, a higher proportion of blue individuals was observed among wild-born Arctic foxes compared to the proportion of blue foxes released from the captive population. Our field study provides the first evidence for an effect of colour morph on the reproductive performance of Arctic foxes under natural conditions, with a higher breeding propensity of the blue morph compared to the white one. Performance of the two colour morphs was not differentially affected by the climatic variables, except for juvenile survival. Blue morph juveniles showed a tendency for higher survival under colder winter temperatures but lower survival under warmer temperatures compared to white morph juveniles. 5. Overall, our findings do not consistently support predictions of the camouflage or the thermoregulation hypotheses. The higher success of blue foxes suggests an advantage of the dark morph not directly related to disruptive selection by crypsis or thermoregulation. Our results rather point to physiological adaptations and behavioural traits not necessarily connected to thermoregulation, such as stress response, immune function, sexual behaviour and aggressiveness. Our findings highlight the need to explore the potential role of genetic linkage or pleiotropy in influencing the fitness of white and blue Arctic foxes as well as other species with colour polymorphisms. apparent survival, Arctic fox, camouflage, capture–mark– recapture models, colour polymorphism, fitness, reproductive performance, snow coveren_US
dc.rightsAttribution-NonCommercial-NoDerivatives 4.0 Internasjonal*
dc.titleFitness and fur colouration: Testing the camouflage and thermoregulation hypotheses in an Arctic mammalen_US
dc.typePeer revieweden_US
dc.typeJournal articleen_US
dc.subject.nsiVDP::Økologi: 488en_US
dc.subject.nsiVDP::Ecology: 488en_US
dc.source.journalJournal of Animal Ecologyen_US
dc.relation.projectNorges forskningsråd: 244557en_US
dc.relation.projectMiljødirektoratet: 19087015en_US
dc.relation.projectMiljødirektoratet: 18087019en_US
dc.description.localcodeThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial- NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. © 2021 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Societyen_US

Files in this item


This item appears in the following Collection(s)

Show simple item record

Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 Internasjonal