The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Sunday, April 15, 2007

Chimney Swifts Are Welcome at My House
by Ro Wauer

A few days ago, what with our greening environment and seeing numerous migratory birds passing by, it was time to prepare my chimney for returning swifts. This was simply a matter of climbing onto the roof of my house and taking off the metal screening that I had installed last fall to help keep out the rain and cold weather. And within a few hours, as Betty and I sat inside watching television that very evening, we could hear chimney swifts already taking up residency. I had heard some swifts chipping overhead a couple days earlier, they apparently had perched elsewhere awaiting my action to let them in. I can only assume that the birds that immediately entered my chimney were the same as those that had nested there during previous years.

Although chimney swift nesting sites once were limited to dark tree trunks and similar habitats, with the advent of chimneys they soon learned to take advantage of such new sites, thus their common name. They build half-saucer like nests on the inside of chimneys, using their gelatinous saliva to cement tiny twigs together and to the wall. In one nest that John Tveten mentions in The Birds of Texas, it contained 130 twigs, each about the length and thickness of a toothpick, all laid parallel along the longer axis of the nest, forming a half-saucer about four inches across and two inches deep.

A single chimney will be utilized by only one nesting pair, although other individuals that are helpers, usually last year's young, may also be present. A clutch consists of three to five youngsters. Until they are 28 to 30 days old, they are unable to feed themselves, but soon afterward they accompany their parents on their feeding excursions. Then, several family groups may be seen feeding together. Sometimes those flying flocks may number in the hundreds.

Chimney swifts have been described as flying cigars, due to their streamlined body shape and torpedo-like flight. That flight is quite different from other birds, consisting of quick flickering wing beats and then sailing with wings held motionless. At first glance, chimney swifts might be misidentified as swallows, but swifts are not swallows at all. They are members of the same order of birds as hummingbirds, Apodiformes, a Greek word meaning without feet, which is a misnomer because they do possess feet. They are delicate yet strong enough in flight to break small twigs off trees for nesting material. Their diet consists primarily of flying insects and spiders on silken threads, and they skim water surfaces to drink.

Although these flying cigars are numerous in Texas and usually closely associated with humans, they are among our most misunderstood birds. Perhaps that is largely due to their use of the dark interiors of chimneys and other chimney-like structures for roosting and nesting. Perhaps folks that fear bats have the same fear of other species that retire to the dark side. But that is silly because chimney swifts are not only one of our most fascinating birds, but also one of the most beneficial species. They consume tons of insects and thrill us with their amazing aerial gymnastics. Especially during courtship, they fly in twos or threes, circling and diving with utter abandonment. And then they soar with their wings held in a V-shape pattern, a behavior that occurs most often with their mates.

In recent years there has been a rather significant decline in chimney swift populations throughout their range, which extends throughout Texas; they are less common in far West Texas and in the Lower Rio Grande Valley. Because of their decline, Paul and Georgean Kyle, directors of the Driftwood Wildlife Association, have established the North American Chimney Swift Nest Site Research Project in cooperation with the Texas Parks and Wildlife Department. Its purpose is to develop a better understanding of the species and to enhance their numbers. They have even developed chimney swift towers (8-20 feet deep with an external diameter of 11-20 inches) that can be constructed of wood to provide nesting sites for these misunderstood birds. Such sites are utilized by nesting as well as migrating swifts. For additional details about the project, towers, and chimney swifts in general, you may contact the Kyles at Driftwood Wildlife Association, P.O. Box 39, Driftwood, TX 78619; 512-266-2397; or DWA@concentric.net.

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