Lincoln's sparrow is a very secretive species; they are often not seen or heard even where they are common. Only the males are known to sing and their song is unique among the Melospiza genus.[1] They produce a sweet, wrenlike, gurgling song with varied frequencies.[2] First, there are often several rapid, high-pitched introductory notes, which then go into a trill that starts out low, rises abruptly, and then drops.[2][3] Similar to the swamp sparrow, the Lincoln's sparrow has a relatively small song repertoire with an average of 3.7 different song types per individual.[7] However, their complex, multisyllabic song pattern is comparable to that of a song sparrow, whereas the swamp sparrow has a simple, single-syllabic song.[7] They sing most frequently in the morning and only in the beginning of the breeding season before incubation.[2] They often sing while exposed on perches, as well as during flight.[2]