Subject: [Tweeters] Re: early spring? Winter bird song
Date: Jan 17 09:32:43 2010
From: Jim Greaves - lbviman at blackfoot.net


Another cause of singing by [mostly] males in fall through winter is
"practice song" by young birds going into their first winter. Right
now there is a House Finch that comes to my feeders on a daily basis,
incrementally changing to male colors, which SOFTLY twitters when as
comes in from elsewhere, and sometimes while he feeds. In addition,
this is the same kind of song you'd see in hatch-year [HY] birds
still on breeding grounds of some [many? most?] neotropical migrants
in late summer/early fall before their departures, sometimes
attaining adult quality if they were fledged early enough and found
by birder late enough in season. For instance, I saw this several
times a season at disparate locations during a couple of decades
studying Least Bell's Vireos in Ventura and Santa Barbara counties in
CA, some whose parents were feeding another set of nestlings close by
(some of these sets had been banded, so origins and ages of adults
and young were knowable) - Jim Greaves, Thompson Falls MT