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Index of Subjects Hello Betty et al.: As mnay know, white-winged (to varying extent) crows and other black birds are rare but regular in NS and elsewhere. In some it seems to be genuine and permanent partial "albinsm" (properly, plumage leucism), but especially in crows it is also attributed to poor early diet, in which metabolism leading to melanism (which crows have aplenty!) goes awry. Then the white or partly white feathers are replaced by black ones in the later molt. It is also thought that feather parts with black pigments are more resistant to chewing by feather mites and u-v damage. Sometimes, accordingly, the white parts of feathers (e.g. the white "windows" in gull wingtips) are lost from worn plumage while black parts remain intact until molted. A couple of late-winters ago, I believe, Bernard Burke photographed a crow at Sullivan's Pond with huge gaps in middle parts of its flight feathers that I believe was the same crow photographed some time earlier with large white patches in much the same places. Lots of odd things out there. Iam McLaren Quoting John & Betty Lutz <jb@ncma.ca>: > Even though we only watch birds in our back yard , we were very > excited to notice a crow who's wings are white ! At first we though > it was a seagull only to discover it wasn't . > One in a murder of 6 , we believe it to be a baby who also has a > sibling which displays slight variations of white . > We have not yet obtained pictures for our old camera would not do > justice ! If by chance we do get pictures we will share them with you > . > Sincerely yours , Betty > jb@ncma.ca >
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