Hello Tweeters. I'm from Calif. but spend some time up there
as my in-laws live in Tacoma.

My question is: How long do these hummers maintain immature
plumage? I'm hoping that in spring migration all green-backed
males will be Allen's, but I suppose that doesn't follow.
Can anyone comment on identification guidelines for spring
migration?

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STEVE HAMPTON [hampton at gordy.ucdavis.edu]
Dept. of Agricultural Economics
University of California, Davis
Davis, CA 95616 USA
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