Simon Thomsett

Category: Falcons, Raptor Expedition | Date: Dec 15 2008 | By: simonthomsett

The falcon stooped and fell across the sky to rebound among a small flock of birds. She mounted high again, turned and powered herself down for another onslaught. They flew out of sight and the result was unknown.

Since the dawn of man few things in nature have been so exciting to watch. This same scene may well have been witnessed while the pyramids were being built, or by some ancient hominids trudging their way across ankle-deep volcanic dust in northern Tanzania. All would surely have raised an eyebrow and dropped their jaw in awe.

The “stoop” is a weapon used by falcons and some other raptors such as large eagles. It is a trick, a sleight of hand they have up their sleeve to propel themselves faster than any known creature on earth. We all have some inherent primitive wish to see an object arc across the sky to its destination, be it a rock, an arrow or a ball. The trajectory has aim and purpose. A falcon’s stoop looks so set in its path that nothing could alter its headlong rush. Its mastery overshadows the violence.

I have seen the word “stoop” weakened by it meaning to bend over, or to describe a certain part of a front veranda. It is not a very inspiring word when used alone, but when used in Shakespearean prose, such as “She stoops to conquer” the word sends a cold chill down my spine. I will never tire to witness stoops done in play, vengeance and in deadly pursuit.

I was in thick traffic at the time entering a particularly unpleasant area of Nairobi and brooding on bad thoughts. The sky suddenly opened before me and down she came, her wings clipping sharply to her sides. She folded, and shot in a downward slope, then she started flicking her wings again. I knew this to be a “feint,” a false move, meant to confuse, so I looked down and ahead. Streaking along the traffic over the transmission wires and untidy security barbed walls of go-downs, was a flock of mixed birds. They swerved the moment she fell, then carried on as fast as they could. She feinted again and the birds changed direction, but with a few less who took a course over flatter ground. Then she banked over and upside down to get as much leverage from the wind beneath her wings to drop down on her back.

The speed is indescribable for, in a less than a second, she had covered hundreds of meters in a flat unchangeable trajectory and was a blur. Her first stoop was not intended to kill, I am sure, but to separate the flock still more. She curved out in a long spiral into the sky and smoothly turned over inverted again for a second stoop.

She was a haggard Peregrine, and she was perfection. I had taken Tim (the Lanner) out flying the other evening. He has still to take permanent leave and reappears every few days. I asked Jonathan to swing the lure and I gave the camera a go. I am nowhere near as good as Laila but I was impressed by a picture of Tim upside-down, turning and preparing to stoop down and towards the camera.

You can see a few of the top (upperwing coverts) feathers, which are very stiff, bending out from the top of the wing camber. They are obviously in very low pressure, near vacuum, turbulent air. The underside must be in very high pressure air.

There is some aerodynamic reason why falcons like to turn over in a dramatic roll, look over their back, and then use all that latent energy piled up under the wing to surge downwards. It makes sense to use the lifting wing, the wrong way up to hurtle the falcon down. Often at the apex of the inverted roll they row their wings, to fly down. This initial energy throws the falcon down into its dive.

In movies one often sees an airplane that is flying slightly low and parallel, lift up, bank and pull away showing its belly. It is the “must do” flying shot in all films. It is unnatural and from personal experience a bit unnerving. A falcon or pilot can go down simply by putting the nose down, but they would loose that advantage which is the lifting power of the wing to give it that first few seconds of downward force. Down and into that wonder of nature called the “stoop.”

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Tags: Falcons, raptor behavior, stoop