EXTRA-GROUP COURTSHIP DISPLAYS AND OTHER REPRODUCTIVE TACTICS OF SUPERB FAIRY-WRENS

A behavioural study was conducted to investigate reproductive strategi es of female and male superb fairy-wrens (Malurus cyaneus). Such strat egies are of particular interest in this species because males and fem ales form lifelong pair bonds, yet exhibit the highest documented freq uency of extra-pair mating among birds. Zn this study, a conspicuous e lement of behaviour of males was the performance of a courtship displa y involving the presentation of a flower or flower petal. This unusual display was performed exclusively (97%) for extra-group females durin g excursions into neighbouring territories by lone males, and appears to have evolved specifically for the purpose of soliciting future extr a-pair fertilisations. Since displays were never followed by an immedi ate copulation, the behaviour appears most consistent with self-advert isement by males. Females appear to control copulation, and may assess males through their displays. Copulations were rarely seen in this st udy, and the proportion of all observed copulations that were extra pa ir(11%, N = 1) significantly underestimated the frequency of extra-pai r fertilisation (76%) determined from previous DNA fingerprinting stud ies. When and where copulations occur remains poorly known. Consistent with control of copulation by females, males showed evidence of only weak mate guarding, and may follow females primarily for copulation ac cess. The evolution of a unique and context-specific extra-group solic itation display emphasises the significance of extra-pair fertilisatio ns in the mating system of this species.