Chimney Swifts breed in urban and suburban habitats across the eastern half of the United States and southern Canada. They are most common in areas with a large concentration of chimneys for nest sites and roosts. In rural areas they may still nest in hollow trees, tree cavities, or caves. Chimney Swifts forage mostly over open terrain but also over forests, ponds, and residential areas. During migration they forage in flocks over forests and open areas and roost in chimneys at night. They spend the winter in the upper Amazon basin of Peru, Ecuador, Chile, and Brazil, where they are found in open terrain and on roosts in chimneys, churches, and caves.
Chimney Swifts eat airborne insects. Feeding on the wing, they capture flies, bugs, bees, wasps, ants, mayflies, stoneflies, beetles, caddisflies, fleas, craneflies, and other insects. They grab large insects with their bills; small ones go right down the throat. Chimney Swifts feed over urban and residential neighborhoods, fields, grasslands, shrublands, orchards, forests, and marshes, usually some distance away from nest sites. They can also pick insects from branch tips and “helicopter” down through the foliage to flush out prey. Normally diurnal foragers, they sometimes hunt for insects at night around streetlights or lit windows. They have been reported taking berries from elderberry bushes.
Chimney Swifts have been in a long-term, rangewide decline of about 2.5% per year between 1966 and 2015, resulting in a cumulative decline of 72%, according to the North American Breeding Bird Survey. Partners in Flight estimates a global breeding population of 7.8 million, with 99% breeding in the U.S., and 1% in Canada. The2014 State of the Birds Reportlisted the species as a Common Bird in Steep Decline. It rates a 12 out of 20 on the Continental Concern Score. Chimney Swift are not on the2016 State of North America's Birds' Watch List. These birds probably became much more numerous with European settlement and the building of millions of chimneys. But traditional brick chimneys are now deteriorating and modern chimneys tend to be unsuitable for nest sites. Adding to the problem, some homeowners now cap their unused chimneys. Chimney cleaning during the nesting season can inadvertently destroy nests and kill swifts. Logging of old-growth forests can reduce the availability of natural nest sites. To prevent further decline, people may need to preserve existing chimneys or create new structures specifically for swift nesting; designs can be downloaded from theNorth American Chimney Swift Nest Site Research Project.
Chimney Swifts may take up residence in your brick chimney if you leave the chimney cap off. It’s a good idea to keep the damper closed during summer and to schedule chimney cleanings either before or after the breeding season. If you don’t have a chimney, you can build a swift nesting tower with plans from theNorth American Chimney Swift Nest Site Research Project.
Chimney Swift Quick Facts
Average body length: 5 inches
Average wingspan: 12 inches
Size and Shape: Adults measure about 5 inches long and have a 12 inch wingspan. In flight, their wings are shaped like a narrow half-crescent. They have a very short neck, a cylindrical body, and no discernible tail, leading to the nickname of ‘flying cigars.’ Perching Habits: They don’t perch on branches or other horizontal surfaces, but have instead adapted to cling to the side of rough vertical surfaces (such as brick) with their long sharp claws. Ten stiff spines on the tips of their tail feathers help support them.
History: Chimney swifts were originally named in 1758 by Carl Linnaeus, who thought they were swallows. They were later renamed American Swallows or Chimney Swallows. Their closest relatives include Vaux’s Swifts.
Their range is the eastern half of the US and southern Canada. A very similar species, Vaux’s Swifts, live in the Pacific Northwest and in southwestern Canada.
Life Expectancy: Their life expectancy is 4.6 years, but the oldest swift on record was at least 14 years old when it was captured and released by an Ohio bird bander in 1970.
Swifts are “aerial insectivores,” which means they feed exclusively on the wing, spending their days flying overhead and scooping up and eating insects. Swifts even drink and bathe on the wing. They glide down to the water, smack the surface with their bodies, and then bounce up and shake the water from their feathers as they fly away. Nesting: Swifts nest one pair to a chimney and sometimes have a ‘helper’ bird, which may be last year’s baby, to help feed their young. The babies are fed ‘spitballs’ of insects that are gathered by the parents. The transfer of the parents’ saliva to the young is thought to help strengthen the babies’ immune systems. In the summer, un-mated swifts continue roosting together in chimneys, sometimes in large groups.
Their nests consists of tiny twigs that the birds snap off in mid-flight using their feet. In May and June, swifts can be seen fluttering above trees that have some dead twigs on top, looking for suitable nest material. The twigs are transferred from their feet to their beak and then ‘glued’ together using their own saliva to form a half-cup nest on the inside of a chimney or other similar location. A completed nest measures 2-3 inches from front to back, 4 inches wide and 1 inch deep. It can consist of over 250 twigs!
Their nests will not cause chimney blockage, damage or fires.
In pre-colonial times, swifts nested and roosted in large hollow trees. Later, as land was cleared for settlements and agriculture, most of these old trees were cut down, and swifts adapted to using chimneys. Modern building construction often does not include chimneys, and many of the older chimneys swifts have used are being capped or demolished, resulting in fewer available nesting and roosting sites.
Legal Protection: Swifts (and all migratory birds) are protected by the federal Migratory Bird Treaty Act of 1918, which protects over 800 species, their parts, feathers, nests and eggs.
Tips on re-nesting baby swifts:
Keeping a chimney clean and the damper closed will eliminate most of the problems that arise between people and Chimney Swifts. But in spite of our best efforts, there will still be occasions when a nest will fall and very young Chimney Swifts will end up in the fireplace where the parents are unable to care for them. The babies all may desperately cling to the nest, or may be found crawling blindly across the living room floor. Our hearts will go out to these helpless waifs, and we will be tempted to try to feed and care for them ourselves. However, wildlife rehabilitators will insist that it is always best to reunite wild baby birds with their parents – whatever the species. Because of their specific diet, handling and housing requirements, this is particularly true with baby Chimney Swifts.
Chimney Swifts nest in inaccessible places, and this makes returning the babies to their parents an exceptional challenge. If the babies are feathered they can be placed on the wall above the damper as previously described. Make certain the damper is closed so they do not fall into the fireplace again. If they are not completely feathered or their eyes are not open, the process of returning the young to their parents will be considerably more difficult.
Because the designs of fireplaces and chimneys are so diverse, there is no single solution that will be appropriate in every instance of a fallen nest. Replacing the nest may require considerable innovation, and may not actually be possible. However, there are several options that should be explored. The most important thing to remember is that if the babies are not replaced in the original nest chimney – in approximately the original position in the chimney -- the parents will be unable to feed them. At the very least, the nest must be replaced above the damper in the lower section of the chimney.
One option is to place the nest in a shallow wicker basket and place it on the smoke shelf just above the damper. It must be either weighted or wedged in such a way that when the parents land on it to feed their young it does not tip over. Some rescuers have placed the nest in a basket and lowered it into the chimney from above. Others have had good results taping the nest to a broom and wedging the broom in a corner of the chimney above the damper.
If it is impossible to return young Chimney Swifts to their parents, they will need to be taken to a licensed wildlife rehabilitator. In the interim, providing proper temporary housing is essential. Because of their lifestyle, Chimney Swifts need to be able to cling to a stable surface to feel secure. The babies will need to be placed in an artificial nest consisting of a small covered box that is lined with a snag-free cloth. The birds’ claws may become tangled in loosely woven fabrics like terrycloth. An old cotton T-shirt works very well. Do not attempt to feed or give water to baby Chimney Swifts. They are reasonably durable, and can fare very well if kept warm, dark and quiet until they can be taken to a qualified caregiver. However, the sooner they receive care, the more likely they will be to survive the ordeal of being separated from their parents. Your state Parks and Wildlife Department, Game Warden or Department of Natural Resources should be able to help you find an individual or facility that can help.
Note: Chimney Swifts are protected by state and federal law, and a permit from both agencies is required to care for them. Hand-rearing Chimney Swifts is extremely difficult, and has been known to bring even the most accomplished wildlife rehabilitators to their knees.
Additional re-nesting information: https://www.wildlifecenter.org/chimney-swifts-neighbors