Characterising the flight song: repeatable individual variation of Ovenbird song features

The songs of most passerines have been well described; however, songs from some species are more difficult to record and have yet to be characterised. The Ovenbird (Seiurus aurocapilla) flight song occurs rarely, is complex in its syllable composition, and its function is still not well understood. We examine the structure of the Ovenbird flight song using the largest sample of warbler flight songs to date (n = 396, 23 individuals) from autonomous recordings made in Sault Ste. Marie, Canada. We characterised the syllable repertoire of this song, examined song syntax, compared syllable sharing among males, and estimated repeatability of several song features. Syllable repertoires varied among males and they appeared to transition differently between syllables while singing, but we found no evidence for syllable sharing between neighbours. Male Ovenbirds were significantly repeatable in the syllable compositions of their flight songs, but repeatability estimates were lower for terminal compared to introductory segments. We find weak evidence of a negative relationship between song features at the within-individual level, suggesting that individuals also demonstrate considerable plasticity when singing. Understanding variation in the Ovenbird flight song will lead to a better understanding of the function(s) of this song type.