Friday, February 18, 2011

Leucism at the Cathedral

Occasional correspondent Robert B. Schmunk wrote on 2/17/11:

Marie, Readers of your blog still working out the difference between albinism and leucism in birds might want to venture up to the grounds of the Cathedral of St. John the Divine. One of the three peacocks who roam the close on the south side of the cathedral is leucistic, a condition which is apparently relatively common in peafowl. This particular bird is also a bit of a show off and can sometimes be found displaying and cadging treats from tourists near the Peace Fountain. Attached is a photo I took of him in 2009.

I wrote back with a question:

Thanks Robert. One question: Why does the bird look so enormous - bigger than the yellow-flowering bush, for instance? Just the camera perspective?


I expect it's just the perspective. I was probably crouching a bit
when I took this and he's perched on an ivy-covered fence that's
3 or 4 feet high.


Thursday, February 17, 2011

Is she his daughter?

Pale Beauty on roof of nest building, Feb 13, 2011
photo courtesy of

Reader Michelle Brown asks:

Has anyone raised the question that Pale Beauty could be one of Pale Male’s offspring? Not sure that it matters, but it seems reasonable.

Blakeman provides an easy answer:


Although the pale plumage of Pale Beauty mirrors that of Pale Male, she can't be an offspring of Pale Male. She's only in her third year, as revealed by the light-brown color of her irises. Pale Male has not sired any eyasses in the last three years.

And the pale colorations of both of these birds, although distinctive and uncommon, is well known and a normal constituent of eastern Red-tailed Hawk populations.

--John Blakeman

Wednesday, February 16, 2011

Leucism vs. albinism

Pale Beauty over Fifth Ave. February 13, 2011
photo courtesy of

Yesterday a reader named Laura Peterson sent in a question which I forwarded to John Blakeman. Laura's question and Blakeman's answer are below:
Marie ,
Just finished reading John Blakeman's blog in which he stated that he feels sure that Pale Beauty has leucistic genes. It would be just wonderful to have a pure white red-tailed hawk in Central Park. Question is - can albino hawks survive in the wild since they don't have their original colored feathers.
Laura Peterson

Blakeman replied:


Albino hawks, those without any body pigmentation (which is known but very rare in Red-tails), do have a multitude of physiological and perhaps psychological problems. True albino Red-tailed Hawks seldom survive their first year.
But Pale Beauty is not, and will not become an albino. She has normal pigmentation in all of her organs and tissues, with the exception of the tail feathers. She, properly, has leucistic pigmentation. Leucistic Red-tails are rather well-known, as leucisticism in this species is far more common than in any of the other Buteo hawks such as Red-shouldered Hawks, Broadwinged Hawks, Rough-legged Hawks, or several others. Just why leucisticism is so common in Red-tails is unknown. But clearly, it conveys no survival difficulties. A very white leucistic Red-tail can survive and breed as well as a normally-pigmented adult.
It was originally thought by some ornithological ethologists (bird behavior experts) that the red tail of the Red-tailed Hawk was an important signal of sexual maturity and species identification. But that thought has been negated by the numerous leucistic Red-tails with white tails that have mated (pair-bonded), copulated, incubated, and raised eyasses from normally-colored mates. The question then still remains, why are the tails of this species so prominently colored? There are a few other Buteo species in Africa and South America that also have nearly identical red tails. We don't know the Darwinian origin or function of this tail color in the Buteo species that have it.
Sure is nice to watch, however.
So no, Pale Beauty will not be restricted in any way with the emergance of new white feathers in coming years---should that be the case (and I think there is now a high probability of this).
Thanks for the good question.

--John Blakeman


Tuesday, February 15, 2011

Help for the hungry

Brown Creeper about to sample peanut butter-and-suet mixture at feeders on Sat 2/12/11
photo by BARRIE RAIK

PS Pretty great camouflage, what?

Monday, February 14, 2011

Happy Valentine's Day

Pale Male and Pale Beauty over Fifth Avenue 2/12/11

John Blakeman wrote the note below to the hawkwatchers at the Franklin Institute in Philadelphia It applies as well to the Fifth Ave pair:

"Yes, the 2011 nesting season has begun in earnest. All of what you saw indicates this. The frequent copulations (not, properly, "matings") indicate that the lengthening days are affecting the birds' endocrine systems. Breeding hormones are flowing copiously. The tiercel is acting in response to these, including the bringing to the nest of the sticks (and later, leaves and such, for lining), along with the frequent copulations. The formel will do a lot of sitting around, watching the hectic activities of the tiercel, thereby prompting eventual ovulation.
The snow and cold have absolutely nothing to do with any of this. It's all controlled by the increasing length of the days, nothing else.
All of this indicates that the pair remains fully bonded, and will replicate the previous years' successes (barring unforeseen calamities).
Spring is on its way, snow and cold (both in Philadelphia and northern Ohio)* notwithstanding. Once again, a new Red-tail breeding season is wonderfully underway.
--John Blakeman

PS from Marie:
Tiercel = male hawk
Formel = female

* and in NYC as well

Sunday, February 13, 2011

Pale Beauty - why so pale?

Pale Beauty on the snow 2/11/11
photo courtesy of

Yesterday John Blakeman wrote:

It now clear that Pale Beauty is leucistic. [note from Marie: Leucism is a condition that affects birds' feathers and turns them pale or white.]
.’s recent photos of her show two such traits. First, the shafts of her central tail feathers are decidedly whitish, along with weak pigmentation in much of the rest of those feathers.
But more importantly, she has an almost pure white (and a bit foreshortened) outer left tail feather. This is markedly leucistic.
As she ages, in the coming years, I will expect more and more primary wing and tail feathers to molt out white. In a few years, she might be almost entirely white.
There is now no doubt that she has leucistic genes.
–John Blakeman

A second note from Blakeman followed:


More comments on Pale Beauty’s tail feathers and their coloration.

A center tail feather is stubbed off, having lost most of its length from an injury. Pale Male lost the tips of his fourth and fifth primaries of his left wing. Pale Beauty lost most of the length of a central tail feather. The pair shares some feather injuries.

Secondly, two of the tail feathers, including the one adjacent to the left, outermost white feather, lack the normal dark sub-terminal bands. This anomaly is yet another indication of leucistic genes. The lack of a sub-terminal band is seen in a small fraction of Red-tailed Hawks, but it normally occurs in all the tail feathers. In those cases, there is no association with leucisticism. Not so in Pale Beauty’s case. She’s lacking the band in only three feathers, the white one and two red ones. This non-unilaterality or pattern unevenness is another trait of Red-tail leucisticism.

As I mentioned previously, all of this indicates a strong chance that each ensuing annual molt will exhibit increasing numbers of white feathers. In a few years, we could have an angelic white Red-tail gracing the skies of Central Park. I have seen these birds in the wild, and trapped and studied one. They are profoundly majestic. "Pale Beauty" is now even more applicable.

I've attached a photo of a leucistic Red-tail that had been injurred and was in the care of an Ohio raptor rehabilitaion facility.

–John Blakeman