Wednesday, June 22, 2011
Monday, June 20, 2011
Photo courtesy of palemale.com
Pale Male nabs a large meaty pigeon at the Metropolitan Museum.
Photo courtesy of palemale.com
And Pale Male's hunting skill translates into extremely full crops for his young.
Photo by Richard Fleisher
REGARDING THE FORDHAM FAB FOUR FROM RED-TAIL EXPERT JOHN BLAKEMAN-
I note with peculiar interest the Fordham Four. I've never encountered a Red-tail nest with 4 eyasses anywhere in the Midwest or East. These are sometimes reported in the West, where ample ground squirrel prey populations can provide the nutrition needed to produce 4 fertile eggs and to feed 4 eyasses to fledging.
Clearly, the Fordham Four indicate the very large prey populations in NYC, probably a combination of rats and pigeons. Rats alone may be the factor.
The colonization of urban areas by Red-tailed Hawks is not complete, I believe. As more and more of these hawks learn to uniquely exploit urban rat and pigeon populations hawk population densities will continue to elevate.
And no one, to my knowledge, is conducting a scintilla of proper field biology studies on any of this. It's still only street theater -- of the highest quality, but in the utter absence of any raptor science.
If I took an hour or two, I could lay out probably several dozen questions about all of this that need detailed study, particularly because urban RTH behaviors contrast so greatly with those in rural areas. For example, rural red-tails simply spend no time trying to pursue pigeons, even though many barns and farming operations have ample populations. Rural pigeons are simply too fast and alert to be captured by red-tails. Different story -- yet untold in proper detail -- in urban areas.
Still, I'm astounded at the Fordham Four. Until now, I would have predicted 3 as the effective upper limit of RTH broods in NYC. These urban hawks have proved me wrong once again, based upon what I know of the rural populations.
I too was astounded by Rose and Vince's ability to raise four eyasses in the first place particularly without any evident change in their behavior noted by observers.
For those unfamiliar with the Fordham nest, only those birds on the edge of ledge can be seen from the ground. Therefore all four of the eyasses would have to have stood on the edge at the same time in order to get a true count. It wasn't until Rich Fleisher was able to get a roof view from another building that the first foursome of eyasses in NYC hawkwatcher memory came to light.
I've not seen nor heard tell of four eyasses of near fledge age surviving in Wisconsin where one or two seems to consist a clutch. Whereas three had seemed to be the New York City limit previously.
I"d read in the literature that some pairs were observed in Alaska with five eyasses. It did not however mention what the main food source prey was for those particular nests.
I received a call from Hawk Bench fixture Stella Hamilton about what prey was going into Pale Male and Ginger Lima's nest.
Stella had promised herself that if Pale Male's nest ever had babies in it again, that she'd buy herself a birding scope. He did so she did. The Stella Scope is now frequently at the Hawk Bench set low on its tripod so even kids can get a good look.
Therefore using the Stella Scope, Ms. Hamilton has been keeping a close watch on what prey is being brought to the nest. And according to Stella the percentage of pigeon and other bird meals have far out stripped that of mammal, including the rats that make us bite our nails, as they might be poisoned.
Which is extremely good news. Even so keep your fingers crossed that a bad rat doesn't go up to the nest some day.