Dataset Information

Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate.

ABSTRACT:

Background

Empirical tests that link temperature-mediated changes in behaviour (activity and resource selection) to individual fitness or condition are currently lacking for endotherms yet may be critical to understanding the effect of climate change on population dynamics. Moose (Alces alces) are thought to suffer from heat stress in all seasons so provide a good biological model to test whether exposure to non-optimal ambient temperatures influence seasonal changes in body mass. Seasonal mass change is an important fitness correlate of large herbivores and affects reproductive success of female moose.

Methodology/principal findings

Using GPS-collared adult female moose from two populations in southern Norway we quantified individual differences in seasonal activity budget and resource selection patterns as a function of seasonal temperatures thought to induce heat stress in moose. Individual body mass was recorded in early and late winter, and autumn to calculate seasonal mass changes (n?=?52 over winter, n?=?47 over summer). We found large individual differences in temperature-dependent resource selection patterns as well as within and between season variability in thermoregulatory strategies. As expected, individuals using an optimal strategy, selecting young successional forest (foraging habitat) at low ambient temperatures and mature coniferous forest (thermal shelter) during thermally stressful conditions, lost less mass in winter and gained more mass in summer.

Conclusions/significance

This study provides evidence that behavioural responses to temperature have important consequences for seasonal mass change in moose living in the south of their distribution in Norway, and may be a contributing factor to recently observed declines in moose demographic performance. Although the mechanisms that underlie the observed temperature mediated habitat-fitness relationship remain to be tested, physiological state and individual variation in thermal tolerance are likely contributory factors. Climate-related effects on animal behaviour, and subsequently fitness, are expected to intensify as global warming continues.

SUBMITTER: van Beest FM

PROVIDER: S-EPMC3679019 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate.

van Beest Floris M FM Milner Jos M JM

PloS one 20130611 6

<h4>Background</h4>Empirical tests that link temperature-mediated changes in behaviour (activity and resource selection) to individual fitness or condition are currently lacking for endotherms yet may be critical to understanding the effect of climate change on population dynamics. Moose (Alces alces) are thought to suffer from heat stress in all seasons so provide a good biological model to test whether exposure to non-optimal ambient temperatures influence seasonal changes in body mass. Season ...[more]

PMID: 23776584

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Dataset Information

Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate.

Background

Methodology/principal findings

Conclusions/significance

Publications

Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate.

Similar Datasets

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