The lifetime breeding success of male Pied Flycatchers was evaluated over a period of nine years (1991-99). The breeding success of males recorded in at least two breeding seasons, and nesting at least once in the study area, was analysed. The lifespan number of offspring was positively and significantly correlated with longevity. The reproductive investment in the first year of life did not correspond with longevity, and hence non- breeding males in the first year did not compensate for the losses in fecundity. There were no differences in longevity between dark, intermediate and female-like coloured males. Darker males were less successful in their breeding attempts in the first year than paler birds. Breeding in the first year of life positively influenced the future number of fledglings, and the greater investment in reproduction in this year positively affected future brood size in dark males. Among males successfully breeding in the study area from their first season, dark males reared significantly more offspring during their lifetime, and in the first year of life, than paler ones. Nevertheless, in the total sample, lifetime brood size did not vary between differently coloured males, perhaps because dark males are more vulnerable to predators. The general difference between differently coloured males lay in how breeding efforts were distributed during life. Dark males can maximise reproductive investment from the first breeding year, while paler males increased average brood size in the following years of life only.
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