November 16, 2024
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Unusual chimney swift in decline because of loss of habitat

The chimney swift has been described as a flying cigar. In flight, its wings seem as if they are beating independently of one another.

The unusual characteristics of this bird blend well with its historical mystery, for scientists were unable to discover its wintering grounds until 1944.

The swifts are now known to migrate to Peru every fall, retracing their route back to North America each spring. But because they spend so much of their time in the air, many aspects of their lives still remain unknown.

Shortly after young swifts leave their nests, they spend all of their daylight hours on the wing. They snatch insects from the air and skim over open water, dipping their bills into the surface to drink.

When collecting material to build a nest, they simply break twigs from trees as they fly by. Some researchers think they may even sleep while flying, and there is some contention as to whether they can mate in midair.

Chimney swifts are so named because of their habit of nesting and roosting in chimneys. This came about because of the disappearance of large, hollow trees, which they historically used. Luckily, they were able to adapt by using chimneys, wells, silos and the insides of abandoned buildings.

Nests are cemented to a vertical surface by a secretion unlike saliva from the bird’s mouth. Both the male and female do the incubation of four to five eggs, which hatch in about 20 days. Early on, young swifts may not spend as much time in the air as their parents. Because they cannot perch, they rest by clinging to nearby walls with long, sharp claws suited for this purpose.

Swifts are distinguished from swallows by their shape, manner of flight and their voices. They have slender, cylindrical bodies – hence the comparison to cigars – and long, crescent-shaped wings, which do not bend at the joints like swallows’ wings do. Their tails merely look like an extension of their bodies, being squared-off at the tip. Their wing beats are stiff and very rapid, and give the illusion – as mentioned above – that they are alternating beats.

Swifts are very vocal, and you will often become aware of their presence above you by their constant twittering.

As with other Neotropical migrants, swifts have been declining. This is again due in part to habitat loss. Many people cap or screen their chimneys, preventing the swift from nesting; new chimneys made of metal have surfaces too slick for swifts to cling to or build on.

To find out how you can provide alternate nesting sites for chimney swifts, send a business-size SASE to The Driftwood Wildlife Association, 1206 West 38th St., Suite 1105, Austin, Texas 78705.


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