Red plumage and its association with reproductive success in red-capped robins

Abstract

Red plumage is produced mainly by deposition of carotenoid pigments into the feathers and is assumed to be costly. Recent studies suggest red plumage may be a condition-dependent, sexually selected signal. To date, few studies have explored the relationship between carotenoid-based plumage colour and genetic (realised) reproductive success. This is despite the rarity of genetic monogamy among avian mating systems. We studied this relationship in the red-capped robin (Petroica goodenovii) across two breeding seasons, using spectrophotometric techniques to score colour and molecular markers to assign paternity. Males with the highest within-pair reproductive success during the first season mou..