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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A few hooded mergansers, small fish-,insect- and crayfish-eating ducks of wooded ponds, can be found year round in northern New England, but their numbers swell in March and April, when many migrant birds return to breed, and others stop over on their way further north. Standing dead trees, or snags, provide nesting cavities for these beautiful, “hammerhead” crested ducks. (Male hooded merganser on left and female on right in photograph.)
As dusk approached, a Redhead (Aythya americana) drake repeatedly disappeared under water, coming up with a mouthful of aquatic vegetation each time it dove. Suddenly an agitated Crow started cawing nonstop. Soon thereafter a Bald Eagle soared overhead, scanning the open water for its next meal. The Redhead immediately dove, and wasn’t seen again for several minutes. Knowing it couldn’t hold its breath for that period of time, I began looking more carefully for where it had surfaced. Eventually I found it seeking shelter from above, tucked under a snag which had fallen into the pond.