Ecological correlates of song learning in song sparrows

Most studies of song learning have been conducted in the laboratory and thu s little is known about how song learning is affected by ecological variabl es in nature. Taking an ecological perspective, we studied song learning an d territory establishment in a sedentary population of song sparrows (Melos piza melodia). We examined the song repertoires of an entire cohort of male s (41 subjects) hatched in 1992 and compared them to those of potential son g tutors (adults who were present in the young birds' first year). Mic foun d that a young bird learns songs from multiple tutors who were neighbors in his first year and usually establishes a territory among or near these tut ors. The degree to which tutors influenced the repertoires of the young bir ds varied greatly. Adult males who survived into 1993 tutored more songs th an those who did not survive, supporting the hypothesis that a young male's repertoire is influenced by social interactions with adults continuing bey ond the classical sensitive period of the natal summer. The final repertoir e of a young bird in most cases was weighted toward one of his tutors with whom he continued to interact, as an immediate neighbor, into his first spr ing. We found no correlations between potential measures of male quality or vigor and degree of tutor influence.