While chimneys may not strike us as a good place for birds, it can be a cozy spot to certain species. Chimneys are spaces that can provide warmth, safety, and refuge. Whether just roosting for the evening or building a nest and raising a family, chimneys can be attractive spaces to utilize. Keep reading to learn more about birds that live in chimneys for at least part of their life.
Birds That Live In Chimneys
A chimney, especially one that isn’t being used, is sometimes used as a home for several species of birds, such as sparrows, grackles, starlings, and pigeons. However, there is one species that almost exclusively lives in chimneys, and that bird is the Chimney Swift.
These members of the swift family are so closely associated with chimney’s, they were named for it! Chimney swifts (Chaetura pelagica) are small birds that have a slender cigar-shaped body and curved wings that are long and narrow. Their round heads sit atop short necks, and their tails are quite short and tapered. While their mouth is rather wide, their beak is so short that it can be hard to see. Both the male and female chimney swift are roughly the same size, and can measure 4 to 6 inches long with a 10 to 12 inch wingspan. Their plumage is a dark, sooty brown.
At one time, chimney swifts would only make their nests in caves and hollow trees. However, their numbers greatly increased once they started to utilize chimneys since these types of structures are more readily available.
Why do chimney swifts like chimneys?
Chimney swifts have very short legs. They are actually incapable of perching like most birds, so you won’t find them sitting on any branches. Their only method of landing is to cling to vertical surfaces with their sharp nails. Rough cave walls or tall, hallowed out trees meet their needs for protection (enclosed space) and vertical clinging surface. But these specific environments can be hard to find. As cities and towns were built up with tall, brick chimneys, these became a perfect, protected home with lots of vertical clinging space.
Other man made structures that chimney swifts will use include air vents, silos, lighthouses, wells, outhouses and cisterns. These aren’t likely to become roosting sites for the birds unless they are abandoned or very infrequently used, since the swifts would be unlikely to settle anywhere with constant disturbance.
The behavior of the chimney swift is a bit different than many other small birds we are used to seeing in our yards. They stay airborne nearly all day long. They eat, drink, and bathe (by skimming along water) while flying! Only during nesting and roosting overnight do they stop and rest.
Chimney swifts use small branches, twigs, and other plant-based materials to build their nests. They use their saliva, which will harden and act as a glue-like substance, to bind the materials together. Their glue-like saliva also helps to adhere the nest to the inside of the chimney, which prevents it from failing.
Sometimes the mated pair will be joined by unmated birds that aid in rearing the young. After the young have left the nest, several groups of parents and young birds from the same area will gather together and roost in larger groups.
Chimney swifts main food source is flying insects, such as flying ants, mosquitoes, bees, termites, beetles, moths, wasps, and flies. These birds are highly adapted for aerial foraging, thanks to their pointed wings and slender bodies that allow them to maneuver skillfully while snatching insects in mid-air.
Smaller insects can fly right into their wide open mouth, or they can grasp larger ones with their beak. Dawn and dusk is their main feeding time, but you may see them after dark swooping to catch insects attracted by street lights.
Chimney swifts will travel thousands of miles between their desired breeding grounds in North America and their wintering grounds in South America. At the end of the summer when it is time to head south, large groups of thousands of these swifts will flock together. The flock is sometimes observed circling in a tornado-like formation as they funnel into a large overnight roosting site.
Challenges and Conservation
According to Cornell University, the decline of historic brick chimney’s into shorter more modern designs with the openings covered or grated off may be having an impact on population. They are not as suitable for nesting as they once were, which may be contributing to the decline of chimney swifts. In areas with large chimney swift populations, one alternative may be the construction of chimney swift towers to give these birds a safe place to nest and roost.
Other Birds That Live In Chimneys
If you have a bird living in your chimney, it is more than likely a chimney swift. However, chimneys are enclosed and protected spaces that many cavity nesting birds would find attractive. These birds need some sort of ledge or horizontal surface within the chimney to work with, unlike the swift that can attach a nest to the chimney wall.
One of the easiest ways to identify the bird nesting in your chimney is to try and get a good look at it. This may be easiest while it is perching around the roof or flying above the house. Chimney swifts are often referred to as “flying cigars” thanks to their cigar-shaped body. If the bird doesn’t have that iconic cigar shape, then it could be one of the following birds.
Sparrows are small birds with plump bodies that measure about 5 to 6 inches long with a 7 to 9 inch wingspan. While there are many types of sparrows, the most common to find in a chimney are House Sparrows. They are known for nesting in man-made structures and love finding little cavities to squeeze into. These birds have gray underparts with streaky brown backs, and male have a black bib.
Grackles are usually tree nesters, however they will sometimes take advantage of openings in attic, vents, chimneys and other man-made structures. They are larger birds, typically measuring around 12 to 13 inches in length. Males are dark and glossy while females are usually brown. Their bodies are sleek and slender, giving them an elegant appearance. An easy way to tell the difference between grackles and other larger black birds is to look at their eyes. Grackles have yellow or golden eyes, which stand out against their dark feathers.
Starlings are a very common bird in urban and suburban areas. They nest exclusively in cavities, and are always on the lookout for a suitable spot. Unfortunately this can mean chimneys and any other vents in your house accessible from the outside.
These medium-sized birds measure 7 to 9 inches. They have glossy, dark plumage that shimmers in the sunlight with iridescent shades of green, purple, and blue, and are speckled at certain times of the year. They have a long yellow beak that can also help with identification.
Pigeons are a common sight in big cities. They have plump, round bodies covered in gray, blue, and white feathers. They have short legs and small heads with orange eyes and a beak that is slightly hooked. Pigeons make an iconic “coo” sound, which can help you identify them from other bird species. They tend to like hanging out on roofs and may find a suitable nesting spot in a chimney, especially on ledges near the top of the chimney as they won’t be able to fly back out if they get too far towards the bottom.
While not birds, bats can often be confused for other types of birds that live in chimneys. Because they are nocturnal creatures, bats won’t make much noise during the day. Birds, on the overhand, will make chirping noises throughout the daylight hours or in the case of swifts, around dusk when they return to the roost.
How To Tell If There Are Birds In My Chimney
The easiest way is if you happen to see birds flying in or out of your chimney while you’re outside looking at the house. Beyond that, the most common way people are alerted to birds in their chimney is by sound. You are likely to hear scratching, rustling or chirping, or may even notice droppings, soot or other debris falling into the fireplace.
How To Remove Birds From Your Chimney
In this case, the best defense is offense. You should take preventive measures to keep chimney swifts, or any other bird for that matter, out of your chimney. Installing caps and screens will go a long way to deter birds from entering the chimney. You’ll want to do this during the non-breeding season to avoid nesting birds. If you do this during the spring and summer, you’ll need to inspect the chimney first to make sure you aren’t trapping nesting birds inside.
It is also recommended to have your chimney inspected once a year. The inspector can ensure there are no openings that would allow a bird into the structure and look for evidence of bird activity.
Active Bird Nest
Once a bird has made their nest inside your chimney, you only have two choices. Chimney swifts and other native bird species are legally protected by the Migratory Bird Treaty Act. Trying to remove or disturb active nests (removing the nest, removing the eggs, relocating the nest or eggs, or starting a fire) could lead to an expensive fine.
The process of nest building to the young leaving the nest takes place over just a few weeks. You can wait it out and take action to cap the chimney once the birds have left. Or, hire a contractor that is licensed and permitted to legally remove nests. A typical chimney cleaning service is probably not licensed for this, so you may want to check with your local animal control who can direct you to the right people.
Coexistence with Humans
Depending on your situation, maybe it’s not a big issue! If the noise doesn’t bother you and you don’t use your chimney during the warm weather months, you can just let the birds do their thing. In the fall have the chimney cleaned and then you’re safe to use it for the winter.
If you have chimney swifts and you don’t want them in your chimney but you feel really bad about evicting them, you could put up a swift tower in your yard! This way returning swifts have a safe place to nest and you don’t have to feel back about capping your chimney. You can find great instructions and information on the Audubon site here.