Mate guarding and male body condition shape male fertilization success and female mating system in the common quail

In species with female polygamy, pair bonds are frequently established since mate guarding can determine male fertilization success. However, extending the duration of pair bonds also implies reducing the chances of finding new mates. Males face a trade-off between mate guarding and looking for new mates, which can be shaped by their body condition. Here, we investigated the effect of male body condition and mate guarding over the female mating system (genetic monogamy or polygamy) and the male fertilization success in the common quail, Coturnix coturnix, a species with sperm storage and thus the potential for postcopulatory selection, and without paternal care. We monitored 20 females and 32 males. We genotyped them, the 21 clutches laid by these females and a large proportion of the males present in the population, which could have sired the clutches, to perform paternity analyses. We tested whether it is the pairing order or the duration of the pair bond that determines the fertilization outcome in clutches with multiple fathers. We hypothesized that males with better body condition might be able to find a mate faster, reducing the cost of mate switching and increasing fertilization success by spending less time in a pair bond. We observed socially monogamous and polygamous females, and our genetic analyses revealed that broods could be sired by one and by multiple fathers. Female genetic polygamy was more frequent when first matings were with males in good body condition. We detected two or three different fathers in multiple paternity broods. The male that mate guarded for longest was the one that sired most of the clutch. Although males in better body condition seemed to establish shorter pair bonds, further data are needed to confirm this trend.