How birds fly and move in foliage can help you ID them

Identifying small songbirds is always challenging, so any clue that helps narrow the possibilities can be valuable. One very common experience is seeing a small bird fly across an opening and then into a tree or shrub, where it is hidden by leaves. Is it just another chickadee, or is it worth following to try for a better view? The way the bird flies and the way it moves in the foliage offer some subtle but simple clues that can help answer those questions and put you on the path to identifying it more quickly.

How does it fly? All small songbirds fly with alternating short bursts of rapid wingbeats and very brief glides with the wings closed against the body. This is the same pattern that gives woodpeckers and finches their strongly undulating flight path, and all small songbirds have more or less undulating flight. In woodpeckers and finches, the “glide” phase is relatively long, so they descend more, and the pause in flapping is more noticeable. In other songbirds, the glide phase is shorter, so they have quicker and shallower undulations. Warblers tend to swerve from side to side as they fly.

What is it doing in the foliage? Once a bird lands, how it moves in the next minute or two can be a clue to its identity. Insectivores like warblers and kinglets are very active and generally don’t sit still for more than a few seconds at a time. Even when they stay on the same perch, they are flicking their wings or tail, or turning from side to side. Seed-eating birds like sparrows, or gleaners like chickadees and vireos, tend to sit still for longer periods, and they are less “jumpy” when they sit.

These are subtle differences, and they depend on weather conditions, the bird’s motivation, and other variables, so your identifications based on these clues will never be certain. But as a quick assessment to put a bird in a general group, it can be useful, and watching for these differences will reveal other subtle clues and increase your understanding of variations in bird flight and behavior.

This article was published in the July/August 2020 issue of BirdWatching.

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