The chimney swift is one of our most recognizable birds. From daylight to dark from spring into fall, we hear its constant twittering and see these cigar-shaped birds, flying from daylight to dark over our yards in quest of flying insects and other invertebrates. However, what is far less known is that the chimney swift is almost totally dependent on humans to provide them with nesting sites.
Before the arrival of European colonists chimney swifts nested predominantly in hollow trees. However, as a wave of colonists swept westward across America, vast acreages of forests fell to the axe. As these forests were cut, the hollow trees found there also toppled. This resulted in an extreme shortage of suitable chimney swift nesting sites.
Fortunately, for both the birds, and us chimney swifts started using manmade nesting sites. Chimney swifts began nesting in chimney, silos, and barns. The chimney swift’s adoption of this new nesting habit has been extraordinary. According to noted ornithologist, Dr. Roger J. Lederer, “Chimney Swifts are so accustomed to nesting in human-made structures that only 10 instances of the bird nesting in the wild in the last century are known.”