dhogaza
Posts: 525
Joined: Feb. 2006
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Interesting note from the Cornell:
| Quote | | occasionally a bird will lose feathers in a close call with a predator. When this happens the new feathers sometimes grow in white and then change back to the normal color at the next regular molt. This kind of white coloring looks like leucism but is not. |
Interesting ... I was triggered to look by doubting that the cause of apparent partial (pied) leucism is always genetic (i.e. "is it a mutant?"), just because it seems reasonable that physical damage could harm follicles and sometimes lead to a lack of melanin.
Hmmm I guess it's accurate to say that all true leucism is genetic (Cornell says so), but not all birds possessing some unusual white feathers are truly leucistic.
BTW, perhaps the most beautiful red-tail I've seen in the hand was a "pale leucistic" (overall off-white rather than splotches of white intermixed with normal plumage) one. It was the color of milk with a few drops of coffee ... a very pale off-white hinting brown.
So now, after identifying the species, our poster needs to follow the bird around until it molts to see if they come back colored or white! :)
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