Just a dusting of snow can reveal the patterns of tracks that different birds leave, and that pattern tells you how a bird moves (walks/hops). Frequently this knowledge can narrow down the possible species that made the tracks. In general, smaller birds tend to hop and larger birds frequently walk. This may be a result of conserving energy — short-legged birds move farther in a single hop than they do taking several steps, whereas it is more economical for larger birds, with longer strides, to move one leg at a time. In addition, birds that spend time on the ground foraging for food are more apt to walk, placing one foot in front of the other, much as humans do. Mourning doves, ducks, pigeons, and wild turkeys all leave “chains” of tracks, alternating feet as they walk. Birds that live mostly in trees and bushes tend to hop from one spot to another, even when they are on the ground, leaving paired tracks. Sparrows, including juncos, as well as finches frequently move in this way. There’s no hard and set rule, as some birds do both –American robins, ravens, crows and blackbirds are as likely to walk as they are to hop! (Photo shows tracks of Mourning Dove on bottom walking towards the left; Dark-eyed Junco above, hopping towards the right.)
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After the breeding season, American crows begin to gather in small, communal roosts. By early to mid-winter the number of crows occupying a roost reaches its maximum. In the morning, shortly before and after daybreak, crows leave their nocturnal roosts in small groups and fly in all directions leading to feeding grounds. After having spent the day feeding, roughly two to three hours before sunset, small groups of crows gather in pre-roost sites, and from these fly along regular flight lines towards their roost. They are often joined by additional crows at pre-roost sites visited along the way. The closer the crows get to their final roost, the larger the group becomes. The same roosting sites may be used for many years and the number of birds in them varies from a few hundred to many thousands.