Subject: [Tweeters] Brown Crow?
Date: Aug 9 03:08:22 2016
From: Devorah the Ornithologist - birdologist at gmail.com


hi terry,

it sounds like this crow has a genetic mutation that has knocked out one of
its melanin producing enzymes, which probably prevents it from producing
eumelanin. in captive-bred songbirds, this usually is a sex-linked mutation
known as "fawn" or "isabella". there are two mutations that can be visually
recognised. one gives the black regions on the bird a red-brown colour
whilst the other gives the black regions a (paler and less red) beige-brown
colour.

hope this helps.


On Tue, Aug 9, 2016 at 2:47 AM, Terry Sargent Peart <terry.peart at outlook.com
> wrote:

> I work in Maple Valley at the Cedar Hills Regional Landfill. Yesterday, I
> saw a Brown Crow... I was stunned. I had my good bins with me and got a
> good look at it. It was with a few other crows (black) so I was able to
> compare it with them. It was the same size, same beak, acted the same
> (they were on the asphalt parking lot picking at probably maggots that fall
> out of our garbage trailers). The color was even over the whole bird for
> the most part, even the beak. I would compare the brown with that of a
> cowbird.
>
> I've never heard of a brown crow, so what did I see?
>
> Thanks for your help,
>
> Terry
> West Seattle
>
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