In case you haven’t noticed, spring really is on its way. Longer day length, returning birds, increased bird calls and birds songs are sure signs.
So what’s the difference between a bird CALL and bird SONG? There is a rather arbitrary distinction made between these two based on the length and complexity of the vocalization. A CALL is considered shorter and simpler and such vocalizations are produced by both sexes throughout the year. A SONG is longer, more complicated, and is produced by some male birds during the breeding season. With a few exceptions, female birds do not sing.
Calls have specific functions and are given in particular situations. Calls are considered innate rather than learned. Examples of calls include alarm sounds, locations calls, and notes given during fighting. Some calls can actually communicate across species.
Song is considered learned to a certain extent. Song serves to identify one species from another, as well as advertise territory and attract mates. The males of many species of songbirds, also known as OSCINE PASSERINE species, (perching birds in which singing is highly developed) actually have two or more songs, each with different syllables and phrases and involving different repetitions. Ehrlich et al. (1988) report that the brown thrasher is estimated to sing in excess of 3,000 song-types! Quite a “song repertoire”!
By the way, because birds produce vocalizations via a structure called a SYRINX located in the trachea. Many birds can sing with their mouths full or even closed!