Data from: Torpor reduces predation risk by compensating for the energetic cost of antipredator foraging behaviours

Foraging activity is needed for energy intake but increases the risk of
predation, and antipredator behavioural responses, such as reduced
activity, generally reduce energy intake. Hence, mortality and indirect
effects of predation risk are dependent on the energy requirements of
prey. Torpor, a controlled reduction in resting metabolism and body
temperature, is a common energy-saving mechanism of small mammals that
enhances their resistance to starvation. Here we test the hypothesis that
torpor could also reduce predation risk by compensating for the energetic
cost of antipredator behaviours. We measured the foraging behaviour and
body temperature of house mice in response to manipulation of perceived
predation risk by adjusting levels of ground cover and starvation risk by
24-h food withdrawal every third day. We found that a voluntary reduction
in daily food intake in response to lower cover (high predation risk) was
matched by the extent of a daily reduction in body temperature. Our study
provides the first experimental evidence of a close link between
energy-saving torpor responses to starvation risk and behavioural
responses to perceived predation risk. By reducing the risk of starvation,
torpor can facilitate stronger antipredator behaviours. These results
highlight the interplay between capacity for reducing metabolic energy
expenditure, optimal decisions about foraging behaviour, and the
life-history ecology of prey.