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March 2007

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Fri, 9 Mar 2007 20:54:43 EST
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A resident of Tuscawaras Township, Stark County, NW of Massillon, has
reported to me the presence there of a leucistic (almost entirely white)  red-tailed
hawk. He has taken and sent to me a number of definitive photos of  the bird,
along with its normally-plumaged mate sitting in a nearby branch.

As a raptor biologist (and licensed master falconer), I am familiar with
white red-tails. While at BGSU in 1970, I discovered a female white red-tail
that was mated to a normal tiercel. I followed it's reproductive year and
watched it raise and fledge a normal male eyass.

With proper collecting permits, I live-trapped the bird because it had
become the target of local poachers. It was kept for two molts at BGSU before
being later released in a wild area of Nevada, where presumably it was less
likely to be shot.

Albino and leucistic red-tails are seen each year at migration  concentration
points such as Hawk Mountain, Cape May, and the others. Albinism  is somewhat
frequent in red-tails.

There are two forms of white-feathered red-tails, authentic albinos (much
rarer) that have no pigmentation in any surface body part. They retain pale
yellow eyes even into adulthood (if they live that long -- most don't). The
second form is the so-called "leucistic" morph, which retains some pigmentation.
Most leucistic red-tails have variably colored tails or primaries, with an
over-all un-pigmented white coloration.

Interestingly, we discovered with the Bowling Green bird (trapped in
Sandusky County near Fremont) that the moderate pigmentation in the tail and a  few
other larger feathers varied after each molt. One year, several tail  feathers
had angled broad stripes of red across the otherwise white tail  feathers.
Then, in the next year, the tail was almost entirely white.

This, I think, indicates that the lack of pigmentation is not entirely
gene-driven, that perhaps other factors are at play, perhaps not unlike humans
gaining white hair or baldness with age.

Curiously, the reporter of the bird in Stark County says that the bird is
uncommonly wary and easily spooked from perches, more so than typical red-tails.
 That was exactly the case with the Sandusky County bird I trapped 37 years
ago.  In the 70s and 80s I road-trapped and banded several dozen red-tails.
None of  them ever approached the wariness of the white bird.

Therefore, hawkwatchers NW of Massillon should be on the lookout for what
appeared to me to be a gorgeous white gyrfalcon sitting in a distant tree. The
size will be right, the species wrong.

One last comment. The bird is obviously mated and a nest has been
discovered. The local resident who reported all of this to me will be attentive  in not
disturbing the nest site or local nest territory until at least mid-May,  when
any eyass(es) will be out of danger from humans passing beneath. Although
white red-tails are seen each year in migration, the biology of their successful
 mating, copulation, egg-laying, hatching, and fledging is essentially
unknown.

Therefore, please do not attempt to leave any public road and trek across
private land to search for this bird or its nest. Let's let it breed and see if
any eyass is normally colored.

No, this is not a new or rare species. It is, however, one of the rarest
occasions when a white red-tail is known to have pair-bonded and will almost
surely lay eggs. The biology of all of this is most interesting, inasmuch as the
red tail color has often been thought essential for proper pair bonding and
mate  recognition. For the 1970 Sandusky County pair, that wasn't the case.
Let's see  how this pair turns out.

(From the photos of the pair, it appears that the white bird is the larger
female.)

--John A. Blakeman
Huron, Ohio 44839
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