Sunday, January 29, 2012

Leucistic Goldfinch

This seems to be my year for reporting sightings of white birds!

In December 2011 I belatedly reported a good friend’s sighting of a rare albino Barred Owl that occurred in the fall of 2010.
Rare albino Barred Owl - spotted in September 2010  
Then just recently World Bird Sanctuary Naturalist/Fundraiser, Catherine Redfern, took us along with her to Smithville Lake just North of Kansas City to view some of the Snowy Owls that have been spotted there as part of the unusual Snowy Owl irruption this year.  To read about this rare occurrence Click Here
One of the Snowy Owls seen at Smithville Lake in Missouri
To put the icing on the cake, just recently I was excited to see a most unusual bird at my thistle feeder—a leucistic Goldfinch! 
The leucistic Goldfinch who has been a fairly regular visitor to my feeder this winter
To my amazement I began seeing this unusual visitor on a fairly regular basis about two months ago.  However, until just a couple of weeks ago I had been unsuccessful in photographing this wary individual.  On the first few occasions when I saw it at the feeder it was gone by the time I grabbed my camera and changed my lens.  I had even resorted to leaving the camera, with long lens attached, sitting on my kitchen table.  (Martha Stewart would have been proud of my new creative table centerpiece.)  Of course the bird did not reappear until the camera was again safely stashed in my camera bag!   Finally, about three weeks ago, I was able to get a few photos—albeit through the two panes of glass in my kitchen window.

According to the Cornell Lab of Ornithology website, leucism is relatively unusual in birds, and from 2000-2006 Project FeederWatch participants reported fewer than 1,000 leucistic birds out of approximately 5.5 million birds reported each season!  I feel extremely fortunate to have seen this rarity.

Without the normal coloration it is difficult to differentiate between male and female
What is a leucistic bird you may ask—and how is it different from an albino bird?  Although there is some disagreement in the scientific community as to what constitutes the differences between these two mutations, all the experts seem to agree on one point—albinos have pink eyes and leucistic birds have dark eyes.  Albinism is a genetic mutation that prevents the production of melanin in the body, whereas leucism is a genetic mutation that prevents melanin from being deposited normally on feathers.

However, the above definition is a simplistic answer to a much more complicated question, since there are varying degrees of albinism and leucism.  To learn more about this fascinating subject click here

Don’t forget to keep your feeders filled this winter--you never know who might visit!

Submitted by Gay Schroer, World Bird Sanctuary Volunteer/Photographer

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