Birds in the Chimney | Identification, Prevention, & Removal

The moment I stepped into the home, the familiar sounds of rustling and chirping from the fireplace confirmed my suspicions. After years in this line of work, I knew we were dealing with chimney swifts before I even laid eyes on the flue.

These unexpected avian tenants often catch homeowners off guard, but I’ve seen it all before. From finding the birds to removing them, I was ready to handle this tricky task and make sure both the people who lived there and their guests who were not paying attention would soon be settled.

How Do Birds Get in the Chimney?

After years of dealing with these feathered invaders, I’ve seen just about every entry method imaginable. Here’s how birds, particularly chimney swifts, typically find their way into your chimney:

1. Open flue: The most common entry point is simply an open chimney flue. Without a cap or cover, your chimney is essentially an open invitation to birds looking for a cozy nesting site.
2. Damaged chimney caps: Even if you have a chimney cap, it might be damaged or improperly installed. Birds can exploit small gaps or holes to squeeze their way in.
3. Deteriorating masonry: Over time, bricks and mortar can crumble, creating small openings that birds can enlarge and use as entry points.
4. Removal of old nests: If previous nests weren’t completely removed, returning birds might use the remnants as a foundation for new nests.
5. Attraction to warmth: Chimneys often emit warmth, which can attract birds seeking shelter, especially during cooler months.
6. Mistaken for hollow trees: Chimney swifts, in particular, naturally make their bird nest in hollow trees. Your chimney mimics this environment perfectly, making it an attractive alternative in urban areas where such trees are scarce.

Remember, chimney swifts are incredibly agile flyers. They can maneuver through surprisingly small openings, often entering and exiting chimneys at high speeds. This skill, combined with their natural instinct to seek out vertical, cave-like structures, makes your chimney an ideal target.

How to Determine What’s Living in Your Chimney

Chimney swifts are harmless, quite helpful to have around (they’re natural pest control agents), and will leave of their own accord. That said, before you decide you’ve become a chimney swift landlord, make sure you’re dealing with swifts and not bats.

1. Go outside at dusk and observe flight patterns. The easiest way to determine whether you’re dealing with bats or chimney swifts is to see whether they’re coming or going at night. Chimney swifts return home in the evenings to sleep in their swift nests, but bats are nocturnal — if you have bats in your chimney, they’ll be heading out at night to hunt.
2. Compare the noise you hear to the volume of flying creatures you see. Chimney swifts are noisy, particularly when they’ve just hatched. If you hear a racket, you have either a small family of swifts or a very large number of bats. If you don’t see swarms of bats entering or exiting your chimney, you more than likely have chimney swifts.

If you do indeed have chimney swifts, think twice before you commit to removing your new tenants and don’t remove them yourself. Because the Migratory Bird Treaty Act protects chimney swifts, you have two legal options.

1. Wait it out (they are migratory birds and only come to North America during the spring and summer).
2. Hire a licensed contractor to safely and legally remove the nest.

Options For Chimney Swift Removal

1. Wait It Out (recommended)

The easiest and most humane way to deal with chimney swifts is to simply wait until they leave. Here are a few reasons why you should allow these unique creatures to leave your chimney on their own accord.

1. Loss of habitat—The swifts are living in your chimney because their natural habitat has been destroyed due to deforestation. Because they’re unable to stand upright or perch like most birds, they prefer to make their homes in hollowed out trees. They spend 99% of their time in flight and their claws are suited to clinging only to vertical surfaces. Your chimney is, quite simply, the safest place for swifts to lay their eggs.
2. Chimney swifts need your chimney only during the hottest months. They come to North America in the spring and return to South America by early November. They don’t like the cold, so they’ll be out of your chimney by the time you’re ready to use your fireplace.
3. Chimney swifts are great pest control. They eat bugs’ wings, and they will eat flies, bees, wasps, ants, flying spiders, and many other insects that you don’t want in your chimney. The South Carolina Department of Natural Resources says the swift is a very effective natural pest-control agent. It should be a welcome summer visitor to anyone’s home.

2. Pursue Removal

For some, the incredible noise generated by a family of baby birds, like chimney swifts, is simply intolerable. In this case, you may want to go after removal. Be warned: chimney swifts are a protected bird species under the terms of federal law, so removal is not as easy as it seems. Here are a few things to keep in mind.

1. Don’t remove them yourself—Chimney swifts are protected under the Migratory Bird Treaty Act. This means that it’s illegal to move, transport, or disturb them (or their nests and eggs). If you have chimney swifts living in your chimney, even lighting a fire in your fireplace is illegal and the nesting material is a fire hazard.
2. Don’t call a chimney sweep—Standard chimney sweep services are rarely licensed to remove chimney swifts.
3. Do call your local animal control — They can direct you to a wildlife control rehabilitator or relocator that’s licensed for chimney swift removal at both the state and federal level. This is your only legal option when it comes to removal.

Preparing for or Preventing Their Return

Because the birds in your chimney are migratory, they will return every year. Whether you want to maintain a symbiotic relationship with the birds or you’d like for them to find a new home, it’s best to be prepared.

Simply Leave Your Chimney As Is

An annual cleaning should be enough to keep your chimney habitable. They chose it for a reason and you’ll probably see the same family in about six months. Chimney swifts usually mate for life.

Install a Chimney Cap

A chimney cap is a wire cages that surround the top of your chimney. If the swifts have already chosen your home, you have only a few months of the year to put in your cap without disturbing them. Installation must take place during the winter, when the swifts are still in South America.

Build a Chimney Swift Tower

You can apply for grants and partner with a local nature center or conservation groups to cover the costs of building a chimney swift tower. This is a great way to reap the pest control benefits of having chimney swifts around without having to open your home.

Final Thoughts

After years in this field, I’ve come to appreciate the delicate balance between wildlife and our living spaces. Chimney swifts, while sometimes unexpected guests, play a crucial role in our ecosystem. Whether you choose to coexist with these feathered visitors or gently encourage them to find a new home, remember that patience and understanding go a long way.

My advice? Take preventative measures when possible, respect wildlife protection laws, and don’t hesitate to call in the experts when needed. With the right approach, you can maintain a comfortable home while also being a responsible steward of our urban wildlife. After all, a harmonious solution is always the best one – for both you and your feathered friends.