EPOW - Ecology Picture of the Week

Swallow in a Hole

Violet-green Swallow (Tachycineta thalassina), Family Hirundinidae
Crestline, California

Explanation:  Perched on the edge of this cavity in the side of a building in the mountains of southern California is this fearless little observer.  The short bill, white patch by the ear, and slight buff wash on the breast marks this as a juvenile Violet-green Swallow, a fairly common resident of woodlands of the west.

Usually, however, Violet-green Swallows tend to nest in loose colonies and in tree hollows.  

And this is a secondary cavity-nester, meaning that it does not hammer out its own cavity openings.  How could it, with that tiny bill and wide gape adapted for feeding on insects on the wing?  This hole was likely made by a flicker or other woodpecker, and it is now usurped by this swallow family.  

Violet-green Swallows will use nest boxes, which are a useful but only partial supplement to the loss of cavity-bearing snags from forestry practices that remove dead trees.