Mating strategies in the Rock Sparrow Petronia petronia: the role of female quality.

@enWe investigated the breeding phenology and breeding output in relation to female breeding status in the polygamous Rock. Sparrow (Petronia petronia). The proportion of polygamous males was around 0.38 though it varied over the study periods. We selected 169 clutches of which the pair's breeding status was known. Within these clutches, we compared the breeding biology of females that mate monogamously, females that started breeding early with a polygamous male (primary females) and late breeding females that chose an already mated male (secondary females). Secondary females produced significantly fewer fledglings than monogamous females and females who started breeding early in a polygamous system. Our results showed that primary females and females mated with a monogamous male were heavier than secondary females. No age effect was detected. Overall, our results indicate that a female's decision to mate monogamously or late in a polygamous systems was probably not independent of her phenotype (body condition).