The Wind-hoverer

Lee Gass

I was a kestrel, hovering on the North Sea wind just inside the last dike in the Netherlands, looking for voles.  If the wind had been calm or steady, it might not have been so difficult to detect voles running through the grass, even if I could see only grass and never any voles at all.  To be good for running, voles’ trails must be narrow enough to keep me from seeing them, but that means they bump into the grass. If I am lucky, I can see the evidence of their bumping, even if they barely graze it, and catch them because of it.

Especially when the wind is light and the grass doesn’t sway.  But when doesn’t the grass sway that close to the sea in the Netherlands, and when does a kestrel have it so easy?  When doesn’t the dike buffet the wind into a roiling river of chaos?  And when doesn’t the wind whip the grass, making it a million-fold harder to detect the voles’ bumping and grinding?

And with the roiling, it is a whole lot harder to hover.  Not just to stay aloft, but to remain absolutely still in the face of the roiling wind.  Yet I must remain still.  When I’m not, my view of the meadow is very different than it is when I’m standing still, and much less useful to me. When the grass is still and I’m still too, I’m deadly.  Everything that seems to be moving actually is moving, and since the only things moving would be voles it is easy.  It is much harder when the wind whips the grass, even when I am still.  And when I am not still, it is nearly impossible.  I bounced a lot in the wind when I was learning to hunt, and rarely caught voles when it was like this.  But I am a flyer, a wind hoverer, and a killer now.  I’m deadly.

It’s not that I can’t learn to ignore my own bouncing, or that I can’t tell that a vole is running through the grass and kill it, even when the wind is whipping. But that’s not the point.  The point is that even though I can do all those things, I can do them a whole lot better if I do fewer of them at a time.  Bouncing is something I can handle because I’m a wind hoverer.  I’m such a good hunter that I can afford to put out a little effort when I fly because it’s worth it.

So my problem is to stand still with respect to the ground; to hang with motionless eyes, attending to the whipping and watching for the signs.

I imagined myself as a kestrel,
Wind-hovering in the Netherlands
And waiting for voles.

I hang,
And Working like Hell
To stay nailed
To the centre of the Earth,
In the roiling wind,
And waiting for voles.

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This story is based on the research of the Dutch biologist Serge Daan, who showed that while wind hovering, kestrels work very hard to keep their eyes absolutely stationary (within millimeters) with respect to the ground, regardless of the turbulence of the wind.  They work so hard to do this that sometimes their bodies are above their heads, yet their eyes remain nailed to the earth.  The story offers a reasonable explanation of the payoff for them.