Lew Proudfoot wrote:
>
>
> Kroodsma has a discussion about this in his book. Song Sparrows
> apparently learn their songs the first year and don't change them, so
> these incomplete songs would be young birds firming up their reportoire.=
> Interestingly, other birds will adapt to the songs of the birds around
> them, so that early in the spring you'd hear lots of this.
>
I'm not clear on the exact timing of the song learning. In some sp. it
continues to the start or into the first breeding season, I guess.
Around here there are a few birds that remain on a territory year
round, though most migrate, I believe, and in winter sing something less
than a full song --- incomplete phrases or missing some elements.
On the other hand, some birds that have been singing long rambling songs
seem to settle down, before leaving the area, to singing a real song
that contains just some of the elements from their ramblings.
SO perhaps this is a way to decide the question of what the bird is up
to: If the bird eventually sings a full song that includes all the
elements of its earlier, winter time, vocalization, it's probably AHY
while if the song it eventually sings has fewer elements than its
earlier ramblings, it was most likely HY?
Too bad --- I can't find any suggestion in my references that plumage
differences would let one age sosp's at a distance.
What fun!
Steve P
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