[obol] albino pelicans (and more)

Sat Sep 29 14:33:18 PDT 2007

On July 20 my wife and I saw a white Pelican that I first took to be a White
Pelican in a large group of Brown Pelicans at Cape Meares Lake.  I took
photos and based on the coloration of the bill and feet plus the fact that
it showed no black on the wings when it took flight I believe it was an
albino/leucistic Brown Pelican.  I have posted some of the photos to Flickr
at http://www.flickr.com/photos/tom_pix/ (there is an underscore between tom
and pix).  Unfortunately I was looking through my binoculars rather than my
viewfinder when it flew so I have no photos showing wing coloration.

Tom Shreve

Tasgenl at Comcast.net

From: obol-bounces at lists.oregonstate.edu
[mailto:obol-bounces at lists.oregonstate.edu] On Behalf Of Dan Gleason
Sent: Friday, September 28, 2007 1:03 AM
To: Cindy Ashy
Cc: OBOL
Subject: [obol] albino pelicans (and more)

Cindy,

I have never seen any reference to albinism or leucisim in any species of
pelican. Albinism is known in just over 300 species of North American birds,
representing 54 families. Pelicans are not included in this list. I remember
finding one reference to albino pelicans from the Carolina coast that was
reported in The Auk in the 1930s (I can find the exact reference if you
wish) but the author states that the birds seen were most likely White
Pelicans. He noted that White Pelicans were quite rare for that region but
that the presence of more than one albino (I believe that 4-5 birds were
seen) at the same time and place would be far more improbable (nearly
impossible, statisically).

Albinism is most common in species that are highly social, or very
sedentary. Both of these situations favor a strong possibility of
inbreeding. Birds that are found in loosely associated groups tend to have
much lower frequencies of albinism.

Albinism has a genetic basis as it is a defect in the gene responsible for
the production of tyrosinase, the enzyme that converts the amino acid
tyrosine into a chemical (dopaquinone, if you want the name) that is then
converted to melanin, the dark pigment. A complete albino bird has all white
feathers and pink eyes and feet. The pink color is the result of no melanin
to block the color of the hemoglogin in the blood near the surface of the
unfeathered parts. Partial albinos may produce some melanin in only some
portions of the body or may produce so little melanin that the normal
patterns are very pale. 

In birds, some complete albinos may actually have some coloration caused by
pigments other than melanin. Carotenoids cause the red and yellow colors
found in birds and all of these pigments come from plant sources in the
diet. They cannot be produced by the bird's own biochemistry. This can lead
to some very interesting color patterns. Imagine a House Finch with the
normal reddish color but all of the other feathers are completely white - no
browns or dark at all. A male Hairy Woodpecker would be completely white
except for the red on the back of the head. Such carotenoid-colored complete
albinos exist but are rare because complete albinism is also rare.

Dan Gleason

-------------

Dan Gleason

dan-gleason at comcast.net

541 345-0450

On Sep 27, 2007, at 11:35 PM, Cindy Ashy wrote:

Question: has anyone ever seen a leucistic/albino

Brown Pelican?

Cindy Ashy

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