What's Cheeping In Your Chimney
large snag trees from the forests, chimney swifts had to find an alternate nesting structure to survive. They found it in the chimneys adorning the houses that cropped up as settlers pressed westward. Because they were not used during the nesting season, chimneys proved to be excellent substitutes for dead trees. Chimneys also allowed swifts to expand their range into areas that were formerly unsuitable due to lack of trees.
Today some swift pairs still raise their families in natural snags. However, their primary nesting sites are chimneys.
Recent trends in heating methods, chimney construction and maintenance have again severely reduced the availability of nesting sites for swifts. Modern homes today rely much less on wood heat, and a large percentage of homes have no chimneys. Chimney caps also block swifts from many chimneys. In addition, many chimneys are now constructed with metal liners that lack the rough surfaces swifts need for roosting or attaching their nests. As a result, chimney swift numbers have been declining throughout much of their range and in most parts of Missouri since 1966.
Although some natural nest sites still exist, the survival of chimney swifts will likely depend on the continued availability of chimneys.
Chimney swifts are versatile in their habitat use as long as nest sites are available. In wooded areas, they forage for insects above the tree canopy. They also inhabit largely open areas that have scattered woods or tree lines. Chimney swifts are equally at home in urban areas, and they're easy for any homeowner or landowner to attract.
Chimney swifts only eat insects and other invertebrates they catch while flying. These include beetles, flies, ants, termites, mosquitoes, moths and even spiders that are blown aloft. The swift's bill is tiny, but its mouth is wide and extends to the eyes, serving as a basket for scooping small prey from the air.
When they return to Missouri from Peru, chimney swifts look for suitable nesting sites in which to raise their single brood for the year. They need vertical shafts with an inside diameter of at least 11 inches. They seem to prefer shafts with a height or depth of at least eight feet. They attach their nests to the side of the shaft usually a few feet from the bottom.
Using their sticky saliva as glue, swifts construct a small nest of small twigs gathered in flight. The nest resembles a half saucer. Both sexes participate in