Fighting tactics of fallow bucks (Dama dama, Cervidae): reducing the risk of serious conflict

Competition between mate fallow deer (Dama dama), during the breeding season was studied to determine if conflict strategies were consistent with the reduction of risk. Agonistic interactions between males were analysed in relation to age, dominance rank and availability of mating opportunities. The breeding season was divided into two main periods: the pre-rut began when all males had cleaned the velvet from their antlers and ended on the last day before matings were first observed, while the rut refers to the period between the first and last matings. Overall, socially mature males (≤4 yr old) were involved in more interactions than immature (≤3yr old) males. Males established dominance rank largely by non-contact agonistic interactions during the pre-rut and there was substantial carry-over of rank to the rut, when it was correlated with mating success. The mating success of males was skewed; mature males achieved 99.4% of the matings and immature males accounted for 0.6%. A mature male was 13 times more likely to fight than an immature male; the mature males that fought most often did so between 0.4 and 0.5 times per hour. During the rut, the number of fights was positively correlated across days with the number of matings. The majority of agonistic interactions (79%) comprising dyads of immature males, involved antler contact. In contrast, mature males engaged antlers in only 42% of their interactions. Fights between mature males lasted more than twice as long as those between immature males and were more likely to occur between opponents with similar dominance ranks. However, towards the end of the rut formerly mismatched opponents were more likely to fight. Thus males operated conditional competitive strategies to decide when to interact and fight. The persistence of rank order from the pre-rut period to the rut and the tendency for mature males to resolve disputes without antler contact, served to reduce the frequency of fights and therefore the risk of serious injury.