Benefits of a risky life for fallow deer bucks (Dama dama) aspiring to patrol a lek territory

Abstract

Summary Little is known about the relation between male ungulates’ ability to adopt a successful mating strategy during the rut and certain foraging strategies before the rut. In highly polygynous species such as many cervids, males are regarded as pure capital breeders, in that they allocate the energy stored in spring and summer to reproduction. According to the predation risk hypothesis, best foraging strategies adopted before the rut may imply a risk because, in order to invest in body size, males exploit the best feeding areas, even though characterized by higher predation risk. We performed a 9-year research through monitoring 31 fallow bucks in the lekking population of San Rossore, Italy. Among the mating strategies adopted by males, defence of the lek territory was repeatedly shown to be the most successful one. A sector of the study area was characterized by the highest meadow productivity and the highest predation risk. We showed that only those males that exploited the best feeding and yet risky areas before the rut to a greater extent, hereby investing in body size, were subsequently more likely to defend a lek territory. Males that during their life reduced the use of best feeding areas before the rut, were less likely to defend a lek territory during the rut. Among territorial males, which adopted the same spatial and foraging strategies before the rut, only few achieved a high mating success during the rut, suggesting that many other factors (phenotype, experience from previous mating seasons, and that gained as subadult males) along with foraging strategies may simultaneously contribute to explain the variability of mating success among territorial males in a lek.