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SUMMARYIndividual variation in aerobic capacity has been extensively studied, especially with respect to condition, maturity or pathogen infection, and to gain insights into mechanistic foundations of performance. However, its relationship to mate competition is less well understood, particularly for animals in natural habitats. We examined aerobic capacity [maximum rate of O 2 consumption (V O2,max ) in forced exercise] in wild satin bowerbirds, an Australian passerine with a non-resource based mating system and strong intermale sexual competition. We tested for repeatability of mass and V O2,max , differences among age and sex classes, and effects of several condition indices. In adult males, we examined interactions between aerobic performance and bower ownership (required for male mating success). There was significant repeatability of mass and V O2,max within and between years, but between-year repeatability was lower than within-year repeatability. V O2,max varied with an overall scaling to mass 0.791 , but most variance in V O2,max was not explained by mass. Indicators of condition (tarsus and wing length asymmetry, the ratio of tarsus length to mass) were not correlated to V O2,max . Ectoparasite counts were weakly correlated to V O2,max across all age-sex classes but not within any class. Adult males, the cohort with the most intense levels of mating competition, had higher V O2,max than juvenile birds or adult females. However, there was no difference between the V O2,max of bower-owning males and that of males not known to hold bowers. Thus one major factor determining male reproductive success was not correlated to aerobic performance.

Several studies have suggested that peak plumage reflectance in birds matches color preferences used in mate choice. We tested this hypothesis in adult satin bowerbird males that have a short‐wavelength saturated blue‐black plumage with a peak reflectance in the UV. We found that the chroma of the blue (405–480 nm), but not the peak reflecting UV (320–400 nm) portion of the male plumage spectrum was significantly correlated with male mating success. A plot of correlation coefficients between male mating success and plumage saturation showed a well‐defined peak in the blue. This suggests that: 1) blue plumage coloration is more important in mate choice than UV or other colors, and 2) that there is a mismatch between the peak reflectance of the plumage of male satin bowerbirds and the range of plumage wavelengths that are correlated with male mating success. This indicates that it is not safe to infer a role of UV or other colors in mate choice simply because of a peak in plumage reflectance.