Crow with ruffled feathers showing white at base

[Michel]

Posting this photo from a FB group where people are baffled about this picture showing white-ish down feathers on this crow.

People are wondering if this is normal or abnormal.  Could not find any article to explain this, though I have heard about this before (that crows have white at base of some feathers).  Any thoughts?

[Lisa Millbank]

Crows' contour feathers normally have grayish, fluffy bases, and the down is grayish too.  This blog post about messy-looking molting crows has pictures showing a lot of gray peeking out from the black feathers.  We have a book with photos of crow contour feathers from the rump, mantle and breast, and all of these feather clumps have gray bases.

This is an interesting photo, but I think this crow may just be missing a clump of feathers, and we're seeing the exposed gray feather bases that are normally covered by the black tips of the surrounding feathers.  It looks like there's a gap in the plumage, rather than just the feathers being parted by the wind.  Sometimes if a bird has an injury, the feathers at the injury site will regrow without pigment, but the entire feather will be pure white, which is not the case here.  Feathers that are merely plucked out (while fighting with another bird, or a near-miss with a predator) almost always grow back the normal color, so it takes a more severe injury to cause a depigmented feather.

It's also not too uncommon for crows to have anomalous white feathers, usually caused by genetic mutations.  A researcher who banded crow nestlings in New York reported that about 1% had one or more white feathers, and there were also crows with white spots on unfeathered areas like the bill or the feet.  There are sometimes examples of dilute plumage, but I don't think this is the case here because the rest of the crow's plumage looks normal. 

Lisa Millbank

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