![]() Mated birds weave a loose nest of twigs inside a chimney or other vertical surface, using their sticky saliva to hold the nest in place. In a flight display signaling their pair-bond, male and female fly together, calling and gliding together in a downward curve. The birds return to North America in flocks but divide into pairs soon after arriving on the breeding grounds. Sign up for ABC's eNews to learn how you can help protect birds It's now known that Chimney Swifts also winter in Ecuador, Chile, and Brazil very recently, a study found the species as a winter resident in Colombia. In that year, banded birds were reported in Peru, solving “a centuries-old riddle of bird migration,” according to a U.S. Researchers didn't know where Chimney Swifts spent the winter until 1944. At dusk, groups of up to 10,000 swifts may circle in a spectacular tornado-like display before finally funneling inside a large chimney to rest for the night. Riddle of Bird MigrationĬhimney Swifts are long-distance migrants and form large flocks as they prepare for their fall migration. Today, deterioration of brick chimneys and homeowners' increasing use of chimney caps are limiting available nest sites. Historically, they nested in tree cavities, but lacking old trees with suitable holes for nesting, swifts long ago turned to chimneys. Pesticide use and agricultural intensification appear to may be reducing the amount of aerial food available for swifts, while tall buildings, wind turbines, and other structures increasingly occupy the airspace.Ĭhimney Swifts do most of their living in the air, but they must come to earth to breed. What may appear to us as an empty sky is actually an ecosystem full of “aerial plankton” comprising airborne insects, spiders, and other minute lifeforms. ![]() The sky itself is increasingly understood as habitat that needs conservation to minimize impacts on wildlife. Habitat loss is also contributing to these declines. Widespread pesticide use is a major culprit, since swifts and other aerial-insect-eating birds - including Purple Martin and Common Nighthawk - require healthy populations of flying insects to survive. But even in those areas, swifts are becoming more scarce. These birds eat, drink, mate, and even sleep on the wing.Ī symbol of summertime across the eastern United States and into southeastern Canada, Chimney Swifts are most common in areas with an abundance of suitable chimneys for nesting and roosting. While Chimney Swifts (and the world's 100 or so other swift species) do in fact have feet, they're useful only for clinging to vertical surfaces. The family name, Apodidae, means "footless" in Greek. Like another famous group of fliers - the hummingbirds - swifts have long wingtip bones that give them added maneuverability in flight. The sooty-gray Chimney Swift is best identified by its sleek silhouette, often compared to a "flying cigar." Twittering, gliding, and diving, often high in skies above cities and towns, Chimney Swifts are among the most aerial of all birds.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |