Male quality, reproduction, and survival in the great tit (Parus major)

Abstract

Three possible measures of male quality (social dominance, song, and size), reproduction, and survival were studied in a single population of great tits. Winter dominance position on a feeder was related to strophe length (number of phrases per strophe), inversely related to positive drift (decrease of the singing rate of the phrases in a strophe), but not related to song repertoire size. Neither winter dominance position nor song were related to size (wing length, tarso-metatarsus length, weight). Singing capacity was not correlated with individual reproductive success in a single breeding season, using a rather limited data set. However, “better” singers (males which sing longer strophes, show less positive drift, and have larger song repertoires) survived better and had a higher individual lifetime reproductive success (on the basis of a male's recruited offspring of all breeding seasons). Our results show that there exist measurable differences whereby birds that are dominant in winter sing “better”, survive longer, and produce more surviving offspring during their life time. We suggest that differences in male quality are the common cause (direct and indirect) of all these effects.