The bird population on our Littleton, Colorado, farm is typical of other properties in the Temperate Zone of Western North America. We host permanent residents, summer and winter residents, seasonal migrants and intermittent visitors such as Canada geese and cedar waxwings. But one species is especially fickle, inhabiting the farm for extended periods of time and then disappearing for weeks or even months.
Common bushtits are small, long-tailed, highly social insectivores of the Western U.S. which prefer wooded scrublands, pinyon pine woodlands and suburban parks; they have cousins in Eurasia but are the only member of their family in North America. Twittering as they comb trees and shrubs for active or hibernating insects and spiders, bushtits often forage with chickadees and nuthatches. Should one pair build their sock-like nest and deposit eggs, the entire flock joins in the incubation process, huddling together through the chilly western nights.
The flocks on our farm vary from a half dozen to fifteen or more individuals and may appear during any season of the year; they generally move in for a few weeks and, unless nesting has occurred, depart for a variable period of time. I hesitate to call them visitors; rather, our farm seems to serve as their second home, one they utilize on no particular schedule.
