IF THE WEATHER is bad on the day of the bird walk you have signed up for, show up anyway. Somebody will be there.

Sunday morning, eight o'clock. It has been raining steadily since six-thirty. I show up at the visitor's center at Great Falls Park in Virginia only because it has taken me all weekend to borrow a pair of binoculars.

Sure enough, there are four men and a woman in ponchos waiting patiently. Bert Claridge, one of three volunteers who rotate leadership of the walks, takes the point as we move off down the paths that crisscross the park. We quickly run into a downy woodpecker and a red-bellied woodpecker.

"Woodpeckers save us on days like this," he tells me.

"Five below zero, snow, it doesn't matter," one man confides to me. "There's always somebody here for the hike." He tells me that even when Bert's not leading, he always shows up. "I don't think he's missed but once in five years," says my friend.

"Really," I say. "Was he sick?"

"No. House guests."

We walk for an hour and a half, pulling our binoculars out from under our ponchos just long enough to identify two dozen birds, including cedar waxwings, chimney swifts, several types of wrens, a flicker.

Finally, Bert leads us back to the visitor's center. "We'll dry off for a bit, then head upstream for a bit," he says brightly. "It's not raining hard enough to stop."