Strategic use of male alternative reproductive tactics in cooperatively breeding banded mongoose groups

Abstract

Alternative reproductive tactics (ARTs) allow smaller or less competitive individuals to reproduce by avoiding direct fights through sneaky strategies. Within cooperatively breeding groups ARTs are rarely reported, potentially due to difficulties observing male reproductive behaviour in the wild, or reproductive suppression by fellow group members. In societies where all mating opportunities cannot be monopolised by one male, young males could use sneaky tactics as a stepping-stone to gain limited reproductive success while they grow in resource holding potential (RHP). Using 20 years of pedigree, weight, group demography, and behavioural data, we investigated the use of sneaky pesterer ARTs in wild banded mongooses. Instead of a stepping stone, pestering tactics were typically a rare back-up used by males displaced from mate guarding tactics by higher RHP rivals. Additionally, pesterers have lower siring success compared to mate guards, despite similar weight loss costs, which may explain why most males settle for reproductive inactivity rather than use pestering tactics. However, pestering allows younger males to gain access to older, higher fecundity females in the group and may even facilitate inbreeding avoidance. Overall, ARTs provide a viable option for reproductive fitness for some males that lose out on reproductive positions in highly male-skewed groups.