Consortship and mating success in chacma baboons (Papio cynocephalus ursinus)

Chacma baboons (Papio cynocephalus ursinus) show a lower consortship take-over rate and longer consortship duration than the other savannah baboons (Bulger 1993). It has been argued that researchers have focused on atypically small troops with few adult males, resulting in low competition for access to oestrous females. Consortship data from two mountain baboon troops containing seven and four males, respectively, were analysed to determine whether the troop with the greater number of males showed a weaker correlation between mating success and rank due to an expected higher consortship take-over rate. No consort takeovers were observed in either study troop and mating success in both troops was correlated strongly with male rank. The distribution of days spent in consortship amongst the males could be explained by the priority-of-access-model. The degree of cycle overlap determined the number of males observed consorting oestrous females, whereas the number of males did not influence the relationship between rank and consorting activity.