Badlands National Park. We saw relatively few birds, but were delighted to find this Mountain Bluebird near the park headquarters.
These birds increase when people clear forests and put out nesting boxes. On the other hand, populations decline when people convert habitat for single uses, like monocultures or urban development. Most of what we know about their breeding biology is from studying birds using boxes. Much less is known about birds using natural cavities (Power and Lombardo 1996).