Subject: FW: Crows with white primaries
Date: Jul 12 19:39:20 1998
From: Jim McCoy - jfmccoy at earthlink.net


One summer a few years back we regularly saw a couple of "white-winged crows"
hanging around a high school track in Connecticut. I assumed they were siblings.
Both had white secondaries that produced fairly sharply-defined wing patches.
Interestingly, one had bright white feathers, while the other had something more
like a washed-out light grey.

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From: B. Grisim[SMTP:bgrisim at u.washington.edu]
Reply To: bgrisim at u.washington.edu
Sent: Sunday, July 12, 1998 7:10 PM
To: tweeters at u.washington.edu
Subject: Crows with white primaries

I was advised of an unusual crow in the Montlake Terrace area that had
what looked like white splints on its wings last year. This year the
woman that had informed me previously said that the crow had produced
two young with the same characteristics. I went and checked it out and
sure enough there were three crows with varying degrees of white
primaries. They are currently remaining on a territory in a residential
neighborhood, which makes observing them for long periods of time a
little uncomfortable. Nonetheless, the birds show a stronger degree of
white primaries on the right wing versus the left. On one bird, at least
three primaires (numbers 8,7, and 6) are pure white. One of the fledged
young had traces on white on the gape, and chin feathers. On one of the
birds, the first and third claws of the right legs are white as well. I
didn't have enough patience to study them more.

I can imagine that a mutation such as this would provide a plausible
example of how evolution in plumage coloration has occured in the past. I
immediately thought that the coloration resembled that of the Black-billed
Magpie, which made me think that seeing these birds is like seeing a very
small step of speciation in action.

Brent Grisim
bgrisim at u.washington.edu