Photo by Chris Bosak
Footprints of a White-throated Sparrow are impressed into the snow of a sidewalk in New England.

Not all interesting bird sightings involve birds. Sometimes they involve merely the signs of birds, which are everywhere if you look hard enough. When I opened the door this morning to check the temperature about a dozen White-throated Sparrows took off for shelter. But their signs were everywhere on the ground in the form of tiny footprints in the dusting of snow that fell overnight in parts of New England.