[Tweeters] Brown Crow?

Devorah the Ornithologist birdologist at gmail.com
Tue Aug 9 03:08:22 PDT 2016


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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