Inside the World of Spring Migration
Kenn Kaufman has become quite a nature writer. I adored his "cult classic" Kingbird Highway but it was a personal story about his birding big year. This is a whole another animal.
[watching the Geminid meteor showers]
In the sharp, cold air the stars crackled with brilliance, and we stood in silence, gazing upward. Once every few minutes a glowing meteor would blaze across the sky, and we would squeeze each other's hands and keep watching. And then somewhere out in the fields the coyotes started singing. We sensed that they were also watching the sky; their cries had a pensive, solemn tone, as if they had become the voices of the lost wilderness, the voices of Earth. Unseen in the dark they went on and on, with yips, keening howls, mournful wails, an elegy to the sky, calling down the falling stars.And read his description of the courtship display of the pectoral sandpiper:
Standing atop a high hummock, a male makes growling, squawking, coughing sounds, then puffs his body to a ridiculous degree by inflating special air sacs under the feathers of his throat and chest. Launching into the air, he flies with slow, deep, exaggerated wingbeats, looking like a blobby brown balloon, making a series of low, throbbing hoots: doob doob doob...The whole thing is bizarre and more than a little comical. So graceful and strong in normal fight, the pectoral sandpiper transforms himself into a dorky showoff in courtship.But of course none of this is what the book is about. If you think you know anything about bird migration, think again. There's a lot more to it than "birds fly south for the winter."
Some fly a little south, to the southern U.S.; some fly all the way to southern South America. Some species that you see year round actually do migrate a little, you just don't notice it. When I lived in Kentucky I thought the robins went south for the winter--until I encountered a flock of them skulking around in the woods. And if you think there are invisible "flyways" the birds migrate along...nope. Some ducks stick to well established routes, but they're just as likely to be west to east, northeast to south, and crisscrossing all over. Hawks migrate in the daytime when they can float on the thermals; they dislike crossing the dead-air of big lakes. Some birds migrate in flocks but many more go singly. Little songbirds migrate at night and are just as likely to shoot across the gulf of Mexico as not, coming down on the other side with most of their excess fat storage spent.
There are places where migrating birds seem to congregate but they're mostly accidents of geography. Kenn Kaufman has located himself in a prime spot--on the south shore of lake Erie. It's a region he has made famous as a spring migration stop-off for warblers and other long-distance migrants. When they arrive at Lake Erie at daybreak, they have to make a choice whether to go on across the water or stop off for a day to eat and regain energy. Apparently a lot of them stop to take a break--in April, it's a miraculous place for bird watchers. And--as he explains many times--a terrible location for wind turbines.
We didn't use t know that many songbirds migrate at night, nor did we realize just how many of them there were. Picture a large cloud of birds moving north in the dark, and remember--most diurnal birds can't see any better in the dark than we can. They can see the stars overhead and the lights below, but not an invisible blade of deadly whirr right in front of their eyes.
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