Birdseed, water drips and suet blocks have been great for attracting a variety of avian species throughout the winter. But now it is spring, and the breeding season has begun. Is there anything we can do to help the birds nest and raise young?

For most species, the best thing is to leave suitable habitat: plenty of shrubs and trees for shelter, lots of chemically untreated vegetation to serve as insect-rearing habitat, and maybe a few patches of weeds to provide wild seeds. Cavity-nesters like bluebirds, chickadees, titmice, wrens and woodpeckers appreciate nest boxes. Be sure to make the nest boxes to the proper dimensions for the birds you want to attract. Get on the internet and do your homework!

Unusual species require thinking “outside of the box.” One of North America’s unique birds is the Chimney Swift. Chimney Swifts nest inside chimneys! Initially, they used broken-off, hollow trees as nest sites. As humans moved into the landscape, those trees were often cut down for firewood. However, settling humans soon began building chimneys to shunt the smoke from their fireplaces to the outside. In the warm seasons, those chimneys were vacant. Until the swifts spotted them, that is. Enterprising swifts dove into the chimneys and glued their stick-and-saliva nests to the inner walls of the structures. This habit turned out to be a “win-win” arrangement.

Swifts are fast fliers and voracious insect eaters. As they race through the skies, they grab “almost any airborne fly, ant, beetle or any other insect” and gulp them down. Mosquitoes don’t stand a chance in Chimney Swift country. So settlers had insect control, and the swifts had a safe place to nest. At the end of the summer, before temperatures dropped and the fireplace was needed again, the birds would have migrated to South America.

This situation was pretty much the case all over the swift’s range, but it was especially noticeable in Texas. Oberholser (1974) wrote that “From the 1930s through the 1960s, the Chimney Swift greatly expanded its breeding range within Texas.” As the birds bred further west and south, the swift became a familiar sight for many Texans. However, in the 1960s, new homes began to be built without fireplaces. And existing chimneys were capped or screened, supposedly to keep out rain or to prevent sparks from escaping. Of course, this practice excluded Chimney Swifts as well. Since the 1970s, the species has been in steep decline.

Distressed bird-lovers suggested solutions: Uncap chimneys, leave chimneys standing when possible or build free-standing swift towers. Paul and Georgean Kyle promoted this last idea in their book, “Chimney Swift Towers”. This guide details how to construct masonry or wood towers that will attract both nesting and roosting swifts. Many parks and nature centers are putting in swift towers. Some have observation ports to allow the public to watch the rearing of the chicks. Still, more swift towers or chimneys are needed to produce a comeback for the species. 

When we demolished a house on an old rural homestead, we left the chimney standing. Realizing that Chimney Swifts are due back any day now, we rushed to uncap the top of the chimney. Fortunately, the low metal top fell off easily, and there was no screening inside the tower. So, our swift abode is ready and waiting. 

We are listening every day for the rapid chippering of the returning swifts. The birds look like fast, “flying cigars” as they wing their way over the roofs and treetops. “Flight—the bird often rocking from side to side in the air—is jerky, erratic and swift.” Other aerial hunters, such as swallows and Purple Martins, also chase insects, but they don’t have the scythelike wings and rocking flight pattern of swifts. Once you’ve seen and heard swifts, you won’t have any trouble identifying the species. They are pretty distinctive birds!

Let’s all watch for the Chimney Swifts. They are a sure sign of spring and warmer days to come. And uncap your chimney, if you have one! The birds will thank you!

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