Modelling the joint effects of body size and microclimate on heat budgets and foraging opportunities of ectotherms

Abstract

Body size affects the body temperature of an ectotherm by altering both heating rates and the microclimate experienced. These joint effects are rarely considered in the analyses of climatic constraints on ectotherms but nonetheless influence body temperatures and thus activity periods and foraging opportunities. Here we develop and test transient heat-budget models that use height-specific microclimatic forcing to compute the dynamics of size-dependent body temperatures of ectotherms in sun and in shade. We incorporate a model of behavioural thermoregulation and use it to compute potential body temperatures and then to map these to ecologically relevant indices, including foraging opportunit..