Wednesday, March 7, 2012

Peregrine Alert

While I was at the river on Monday I saw a falcon flying some distance away. It was too far away for a definite identification, but three things made me immediately think Peregrine: its relatively large size, the sharp contrast between its dark back and light breast, and the speed and trajectory of its flight. We have Prairie Falcons and Kestrels (commonly known as Sparrow Hawks) around here. The Kestrel is much smaller. The Prairie Falcon is almost as large as a Peregrine, but, as the bird book says, is of a "paler, sandy color," like a "faded Peregrine." Both those birds have a flitting flight, and will often glide, or, in the case of the Kestrel, hover. The Peregrine flies, again according to the bird book, with "quick, rowing wing beats," and it seldom if ever glides. Normal flight has been clocked at 30 to 40 miles an hour, while level flight in pursuit of prey can reach 50 to 60 miles an hour.


I love Peregrines. I have been birding seriously for almost forty years, but it took me a long time to finally see one. Long ago I would go with friends to a State park on the Illinois shore of Lake Michigan to watch the migration of raptors. We never saw a Peregrine, but we often found ducks lying dead with only their brains eaten out. I was informed by a more experienced friend that such selective predation was a hallmark of the Peregrine. Looking at the beak in this photo, I can see how a Peregrine could make short work of a duck brain. The upper mandible has a tooth which fits into a notch in the lower mandible. One of its functions is to be inserted into the neck of a prey bird, where, with a twist, it can sever the spinal cord.


I almost saw a Peregrine once at Hawk Mountain, that phenomenal ridge in Pennsylvania where raptors by the thousands are funneled in by the Appalachians and pour over the ridge just a few feet overhead. I had been watching Ospreys and Redtails, hundreds of Broadwinged Hawks, and many other raptors, form great kettles out over the valley, then peel off and make the crossing. Just as I had to leave and had started the climb down to the trail a woman cried out, "Peregrine!" By the time I had climbed back up it was gone.

Later, in a mid-sized city in Indiana, I saw a Peregrine high over a traffic-choked street. The city had established a nesting pair on the roof of one of its highest buildings. I was happy that this pair had nested successfully, as others had done in cities across the country, in a widespread program to rebuild the population after it had been ravaged by farm and industrial chemicals. But I still wanted to see a wild Peregrine.

"The Peregrine is adapted to the pursuit and killing of birds in flight." So writes J. A. Baker, in Peregrine. They can stoop, or dive, at a hundred miles an hour in that deadly pursuit. Baker goes on:

"Killing is simple once the peregrine has the advantage of his prey. Small, light birds are seized in his outstretched foot; larger, heavier birds are stooped at from above, at any angle between ten and ninety degrees, and are often struck to the ground.....
The peregrine swoops down towards his prey. As he descends, his legs are extended forward till the feet are underneath his breast. The toes are clenched, with the long hind toe projecting below the three front ones, which are bent up out of the way. He passes close to the bird, almost touching it with his body, and still moving very fast. His extended hind toe (or toes--sometimes one, sometimes both) gashes into the back or breast of the bird, like a knife. At the moment of impact, the hawk raises his wings above his back. If the prey is cleanly hit--and it is usually hit hard or missed altogether--it dies at once, either from shock or from the perforation of a vital organ. A peregrine weighs from one and a half to two and a half pounds; such a weight, falling from a hundred feet, will kill all but the largest birds. Shelduck, pheasants, or great black-backed gulls, usually succumb to a stoop of five hundred feet or more. Sometimes the prey is seized and then released, so that it tumbles to the ground, stunned but still alive; or it may be clutched and carried off to a suitable feeding place. The hawk breaks its neck with his bill, either while he is carrying it, or immediately when he alights....
Some soaring peregrines deliberately stoop with the sun behind them. They do it too frequently for it to be merely a matter of chance."

Those who have seen it have remarked on the explosion of feathers when a Peregrine hits its prey.

Two years ago at this time of year I was outside when I saw a dark shape drop like a bomb into a covey of quail in our yard. The covey exploded in flight, and the hawk, which had missed, flew on into the pasture and landed. I was able to approach close enough to identify it. It was a Peregrine. A wild Peregrine. It looked at me calmly as it preened itself, then launched into flight and was quickly gone.

I saw it from a distance a few times after that. I thought then there might have been a pair nesting on the rugged rock face that fronts us just across the road. I still like to think that. And I like to think that they might be there again.

Time to be watching.


(Photos by Steve Wolfe, posted on The Cornell Lab of Ornithology.)

4 comments:

  1. Wonderful post! I like activities like birding,tree and wildflower id. I think it heightens awareness and improves observation. Of course, it's fun too. Accipiters,Raptors, Kestrels are so cool. I thought the point of them diving out of the sun was fascinating.

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    1. Boy, me too. There was much more fascinating information in that book, too much to put in the post. These are amazing birds.

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  2. Fantastic! Truly amazing creatures. There was a pair when I was a child, who would always take up nesting in the Nebraska state capital building...there was a live stream going...and always a "name the chicks" contest. The chicks, who ended up god knows where. Anyway...yay for seeing Peregrines!

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    1. Great story. Bet you've got some up your way. Hope you see one!

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