Ecological and phenotypic effects on survival and habitat transitions of white-footed mice

Abstract

Animals often confine their movements to familiar areas and preferred habitats, resulting in increased fitness through enhanced survival and reproduction. However, the link between preferential habitat use and fitness is rarely tested, especially when individual phenotype is considered. Through multi-state modeling of mark-recapture data, we assessed the influence of habitat type, sex, and body size on the daily survival and habitat-transition probabilities of white-footed mice (Peromyscus leucopus). Habitat states tested were forest edge versus forest interior, and grassy versus shrubby habitat. Females were more likely to survive than males, and mass had a positive effect, whereas foot length a negative effect on survival. Females were more likely to exhibit habitat-type fidelity between edge and interior states than males. Body mass negatively affected daily transition between edge and interior, whereas foot length had a positive effect. Individuals were most likely to remain within the shrubby habitat and leave the grassy habitat. Mass had a negative effect on daily transition probability between grassy and shrubby habitats, foot length had a positive effect, and sex had no effect. Individuals with the greatest probability of moving between habitat types had the lowest probability of survival, likely a result of occupying unfamiliar space. Our results show that white-footed mice in general seem to select habitat types where fitness expectations are likely to be greatest, but that transitions between habitats often depend on phenotypic characteristics of individuals.