The effects of sex, time of birth, and habitat on the vulnerability of roe deer fawns to red fox predation

Abstract

Red fox (Vulpes vulpes) predation on roe deer (Capreolus capreolus) fawns was studied using radiotelemetry techniques on an island in central Norway. Red foxes killed 48% of the monitored roe deer fawns within 60 days of birth, and mortality from other factors constituted only a minor part (5%) of the total mortality. The predation rate was lower in first week of life than during the subsequent 3 weeks. Male roe deer fawns were four times more susceptible to red fox predation than female fawns. We argue that these results reflect differences in behaviour between the sexes. There were some indications that time of birth may be important in determining vulnerability of fawns to red fox predation, with fawns born during the birth peak suffering more predation than fawns born outside the peak. The type of habitat a roe deer fawn used appeared to influence the probability of being killed by a red fox, and our results supported the hypothesis that hiding is a strategy to avoid predation in dense habitats. Fawns killed by red foxes used open grassland significantly more than surviving fawns, which used woodland to a greater extent.