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Nature Reflections - January 26, 2006
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Albinism by Jean Griffin After
receiving a report of an albino Evening Grosbeak in Flinton, I started
looking for more information on albinism. There is a lot of information
on this subject as it relates to humans, but I did not find much on
animals or birds, except one article that said that the various
mutations which result in one or another form of albinism and their
effects have been found to be identical in both humans and non-humans.
So a definition I found which calls albinism "a group of related
conditions that are a result of altered genes that cause a defect of
melanin production, which results in the partial or full absence of
pigment from the skin, hair, and eyes" can be applied to birds and
animals.
The
bird in Flinton was one of a large flock of Evening Grosbeaks (hey, why
am I not getting these birds at my feeders!) and was described as "all
yellow, some white and a buff color - no black or dark brown!" so this
bird still has some pigmentation. How is this going to affect this
bird? Will it be accepted readily by the members of the flock or will
it be at the low end of the pecking order? Will it be more susceptible
to predation because of the colour? Will it find a mate that accepts
it? And if it does find a mate, will its offspring be albinos? We
probably will not know what happens to this particular bird. Over
the years I have had a number of reports of albino birds and animals,
including one Evening Grosbeak that appeared at my feeder a number of
years ago, and was primarily white with a limited amount of
yellowish-buff. I saw it for only a few days, so what happened to it?
With the wandering habits of the grosbeaks it could have moved away. On
the east side of One
thought I have to which I have not found an answer - when the bird
molts is there any chance the new feathers will be more normal? This of
course is not to be confused with the molting of a Rock Ptarmigan,
which living in the Arctic molts from brown to white in the fall, and
back to brown in the spring - a matter of survival in this area and
presumably no relation to albinism. Observations: Thanks to Carolyn Hasler of Flinton for the report on the albino and flock of Evening Grosbeaks. She also has had 5 or 6 Pine Grosbeaks. Helm, in Oconto, had a visit from a Raccoon the night of January 18 - obviously stirring because of the mild weather. He also has several Dark-eyed Juncos, and 4 Mourning Doves. Share your sightings - call Jean at 268-2518 or email currawong13@sympatico.ca.
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