The crows come every winter evening in swarms of thousands. They sail through the cold air, as determined to reach their destination as the hordes of holiday shoppers flocking to White Flint Mall.

One night I decided to follow them to whatever primordial place they were heading. Rather than try to track them by eye in ungainly automotive transport (doomed to follow the twisting highway rather than go "as the crow flies"), I cheated: I called the Audubon Society to find out where they go every day at dusk.

Those birders are on their game: I was directed to a narrow strip of straggly trees between Montrose and Old Georgetown roads, behind La Madeleine restaurant. The trees in this less-than-pristine woods stand defiantly beside the ADC Development trailers that prophesy what's to become of them. According to the Audubon Society, this flock of 250,000 to 500,000 crows has roosted in the Bethesda-Rockville area for more than 100 years.

They are smart survivors that thrive in suburbia, where there's plenty of food (what with road kill and trash) and few owls willing to leave the safety of Rock Creek Park for the neon neighborhood the crows call home. Thousands of birds roost close together, for warmth and protection from the occasional brave owl. I stood with freezing fingers waiting for them. And then, right on time, there they were, flying fast from all directions, an implosion of black forms against the rouged sky. The influx lasted for 45 minutes as the trees filled with a raucous city of birds. I got as close as I could, close enough to see how their feathers looked rumpled and oily and pecked at by panicked sparrows. They bunched together, balancing on branches that sagged from their weight. Individual crows dripped off these teeming black clusters, briefly free-falling before finding their wings and flying to less crowded limbs.

By now the sun had disappeared and the sky had turned campfire orange. In the dimming light, the naked branches looked as if they had sprouted a thick coat of black leaves for the winter. Then one of the leaf clusters leaped into the night air. Another bundle followed. I could hear screams and barks and caws as they streamed toward . . . Barnes & Noble. By the time I got there and drove to the top of the parking garage, most of the birds were settled in four or five treetops that bordered the parking lot. Others had alighted on the empty lot itself and appeared completely at ease on the concrete.

Lesser creatures might have been wiped out long ago from habitat destruction. But not the crows. They're here to stay.

--Catherine Koczela, Rockville

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