Should I stay or should I go now: dispersal decisions and reproductive success in male white-faced capuchins (Cebus imitator)

Abstract

Although males often disperse to increase their immediate access to mates, it is unclear whether they also consider potential future reproductive opportunities. We investigated whether immediate or delayed reproductive opportunities predicted dis- persal decisions and reproductive success of subordinate immigrant male white-faced capuchins in the Sector Santa Rosa, the Área de Conservación Guanacaste, Costa Rica. We collected genetic, behavioral, and demographic data from four social groups across 20 years. We genotyped individuals at up to 20 short tandem repeat loci to determine paternity. Having previ- ously sired offspring in a group did not predict the subordinate immigrant male’s likelihood of staying or dispersing. Instead, a male was more likely to remain in the group if he was younger and likely to benefit from queuing for future reproductive opportunities. Subordinate immigrant males were more likely to sire offspring if they resided with a long-term alpha male and his mature daughters, who avoid inbreeding. Reproductive output was similar among three categories of males: those that became alpha immediately after immigration, those that became alpha after queuing, and subordinate males that resided with a long-term alpha male and his mature daughters. These three categories of males had higher reproductive success than subordinates who did not reside with mature daughters of the alpha male. Waiting for reproductive opportunities can lead to high reproductive success and could be important in maintaining tolerant or cooperative male-male relationships in species with high reproductive skew, long alpha male tenures, and intense between-group mating competition requiring cooperative male group defense.