Birds Nesting in Your Chimney in Seattle: Swifts, Starlings and the Law

If you are hearing chirping from inside the chimney, the answer depends on what bird it is. Starlings, house sparrows and pigeons can be removed along with their nests as soon as we get there. Chimney swifts cannot: they are protected under the federal Migratory Bird Treaty Act, so an active swift nest with eggs or young has to stay until the birds fledge, and the flue is cleaned and capped afterward. Either way, do not light a fire, keep the damper closed, and call us at 206-453-2045 for chimney animal and nest removal in Seattle, Tacoma, Everett and around Puget Sound.

The good news is that you rarely have to guess for long. The sound, the timing and the kind of nest tell us which bird you have, and the fix is the same at the end: clear the flue, then put a proper cap with a mesh screen on it so it never happens again. The only thing that changes is when we can do it.

Which bird is in your chimney?

Chimney swifts

Swifts are small, dark, cigar-shaped birds that look like flying boomerangs and spend almost all of their waking hours in the air. They cannot perch like a songbird; they cling to vertical surfaces with their feet, which is why the inside of a masonry flue suits them. They arrive in the Puget Sound region in spring and leave in late summer or early fall. A swift nest is a small half-cup of twigs glued to the flue wall with the bird's saliva. It is light and does not usually block the flue on its own.

The sound is the giveaway. Swift chicks make a loud, rapid, high-pitched chattering when a parent arrives with food, and it can be startlingly loud through the damper. Outside the house, you may see a pair of swifts circling and dropping straight into the top of the chimney at dusk.

European starlings and house sparrows

These are the birds that actually block flues. Starlings and sparrows stuff the flue or the smoke shelf with grass, twigs, feathers, string and trash, and they come back to the same chimney every year. A starling nest can fill a flue from the smoke shelf up several feet. Their calls are a mix of whistles, chatter and squawks, and you will often see the adults going in and out of the top during the day. Neither species is native and neither is protected by the Migratory Bird Treaty Act, so we can remove the birds and the nest at any time of year.

Pigeons, crows and others

Pigeons nest on wide chimney tops and in open chases rather than inside narrow flues. Crows and jays do not nest inside chimneys but will drop in and get stuck. A single bird fluttering against the damper is usually a trapped bird, not a nester, and needs to come out fast.

What the law says about chimney swifts

The Migratory Bird Treaty Act is a federal law that protects most native birds in the United States, including their active nests, eggs and young. Chimney swifts are covered. In plain terms, that means we cannot destroy an active swift nest, remove eggs or chicks, or harm the adults. What we can do is confirm that it is a swift, tell you roughly how long until the young fledge, make sure the nest is not a fire or blockage risk in the meantime, and schedule the cleaning and cap installation for after they leave. Once the nest is empty, removing the old nest is fine.

We are not going to quote fines or penalties here because we are not lawyers. We will tell you that we do not remove active swift nests, and no reputable chimney company in Washington will either. If someone offers to, that is a red flag about how they do the rest of their work.

Why swifts pick Seattle chimneys

Swifts evolved nesting in hollow trees. Old-growth hollow trees are rare in the city now, so masonry chimneys with rough interior walls are the closest thing they can find. Seattle's housing stock has a lot of them: the median home in the city was built in 1976, and roughly half of the homes went up before the late 1980s, which means a large share of pre-1970 houses with brick masonry chimneys. Tacoma's stock is older still, with a median build year of 1967. Many of those chimneys were never capped, or the cap rusted away decades ago. An uncapped, unlined or clay-tile-lined masonry flue is exactly what a swift is looking for. Smooth stainless liners and prefab metal chimneys are far less attractive to them because there is nothing to cling to.

Is a bird nest in the chimney dangerous?

Yes, for three separate reasons.

• Fire. Nest material is dry tinder. A starling nest on the smoke shelf sits right above the firebox, and in a flue with creosote buildup it can start a chimney fire the first time you light up in October.
• Carbon monoxide and smoke. A blocked or partly blocked flue does not draft. Smoke rolls back into the room, and with a gas appliance venting into the same flue, combustion gases can back up without any visible smoke at all.
• Mites, odor and disease. Bird nests carry bird mites that migrate into the house when the birds leave. Droppings and a dead chick or two produce a smell that gets worse on warm days, and dried droppings are not something you want blowing into a living room.

If you have a gas fireplace or a gas furnace venting through the chimney and you suspect a blockage, stop using the appliance and call us. If you ever smell gas in the house, leave and call your gas utility or 911 from outside.

What not to do

• Do not light a fire to drive the birds out. It does not work, it kills the birds, and with swifts it is illegal.
• Do not go on the roof. Seattle roofs are slick and mossy for much of the year. We have the ladders, the fall protection and the tools.
• Do not spray water or chemicals down the flue. It creates a wet plug and does nothing for the birds.
• Do not open the damper to look. A trapped bird will come straight into the room.
• Do not put a cap on over an active nest. Trapping birds inside means dead birds inside, and for swifts it means breaking the law.

How we handle bird nests

We start by confirming what bird it is and where the nest is, from the top and from the bottom, with a camera if the flue is tall or offset. For starlings, sparrows and pigeons we remove the birds and the nest the same day where possible, then do a full chimney cleaning to clear every bit of nest debris, droppings and feathers from the smoke shelf and flue. This is different from a routine sweep; a sweep removes creosote from a working wood-burning flue, while cleaning deals with blockages, debris and the smell a nest leaves behind. Then we install a cap with a mesh screen so the birds cannot come back next spring.

For chimney swifts we do the first visit the same way, but if the nest is active we stop there. We tell you what you have, what the timing looks like, and we put the cleaning and the cap on the schedule for after the swifts have gone. If you want the cap done before next spring so they do not return, late summer through winter is the window. Some homeowners actually like hosting swifts and ask us to leave the flue uncapped; in that case we recommend at least an annual cleaning and a chimney inspection before the heating season so the flue is clear and safe when you light the first fire.

Preventing the next nest: the cap

Every bird nest we remove comes down to an open chimney top. A stainless steel chimney cap with a mesh screen is the only permanent fix. It keeps birds, raccoons and squirrels out, keeps rain out of the flue, and keeps sparks in. On a framed chimney, the equivalent is a sound chase cover; a rusted cover with gaps is a standing invitation. If the cap is the only thing you need, we are happy to come out just for that, with a free quote and same-day service when the schedule allows.

What to do next

Keep the damper closed, leave the fireplace alone, and call 206-453-2045. Tell us what the chirping sounds like and whether you have seen the birds going in. We will tell you whether it is a swift or a starling, what we can do and when, and give you a free quote on the cleaning and cap. We serve Seattle, the Eastside, Tacoma, Everett and the road-accessible Puget Sound from our Renton office. If you already have a bid from another company, bring it: we give a free second-opinion quote and will match the price with a 10 to 25 percent discount. And if you are not happy, we are not done.

Related

• There's an Animal in My Chimney — What Do I Do?
• 5 Signs Your Chimney Is Blocked
• Chimney Animal & Nest Removal service