Without question, the backyard bird that spends more time flying each day throughout the spring and summer than of our other feathered backyard residents is the chimney swift.
From dawn to dusk, the bird Roger Tory Peterson dubbed the flying cigar is on the wing. Biologists estimate that a chimney swift is capable of flying 140 miles every twelve hours. During the nesting season, when the birds are feeding young, adult chimney swifts typically forage within 0.3 miles of their nest. Although their flights can take them upwards of as high as 7,300 feet above the earth, most of the time, these aerial forays are much closer to the ground.
Interestingly, in cities and other areas illuminated at night, chimney swifts will even hunt for insects attracted to outdoor lighting. This begs the question, “When do they rest?”
Indeed, feeding a nest full of hungry nestlings is quite a chore. It has been estimated that a pair of adults feed their voracious offspring the equivalent of 5000-6000 housefly-sized insects a day!
The diet of the chimney consists mainly (95%) of flying insects and spiders. On the average, a chimney swift can eat as much as 1/3 its weight daily. Among the delicacies consumed by chimney swifts are wasps, bees, aphids, mosquitoes (as many as 17,500 per day), ants, flies, and termites (up to 280 per day) to name but a few. It should be noted that chimney swifts are a significant predator of fire ants. In addition, they also capture tiny spiders drifting along in the wind on thin webs.
You would think that these small aerial wonders would pause to rest from time to time on a branch or utility wire. The truth of the matter they are incapable of perching upright. For the reason, when they are roosting in your chimney they use their tiny claws to cling to the vertical surface of the chimney.
I think you will agree the chimney swift is one of our most fascinating backyard residents.