Chirping or wings in the flue? Telling swifts from bats

Chattering, rustling or scratching?

Is something alive up in the flue? The sound itself is your first clue. Chimney swift chicks make a loud, rasping chatter that rises every time a parent drops in with food, many times a day, and fades when the adult leaves. You'll hear it most in daylight, and it can go on for a few weeks while the young grow.

Bats may make squeaks or rustling sounds, but sounds overlap and activity at dusk does not settle the identification. Swifts can also gather at chimney roosts near sunset. Observe only from a safe distance and avoid disturbing an occupied chimney.

Heavy scratching, thumping or an unfamiliar odor may involve another animal or another cause. Leave the fireplace unused and seek appropriate guidance. Do not change dampers, block exits or close a vent that may serve gas logs or another appliance, and never try to smoke animals out.

Telling a swift from a bat at a glance

A chimney swift is a slim, sooty-gray bird with long, curved wings, a shape birders like to call a cigar with wings. It can't perch on branches the way most birds do. Instead, it clings to vertical surfaces with tiny claws, which is why the rough inner wall of a masonry chimney suits it so well.

Swifts are often seen in daylight and may enter communal roosts at dusk. Bats also use evening hours, so timing alone cannot distinguish them. Debris and droppings should not be handled to identify an occupant; seek suitable wildlife guidance when the species is uncertain.

Identification may require a wildlife specialist. A chimney service can discuss visible conditions and the work that may follow, but should not promise to identify every animal from debris or a brief look. Confirm occupancy before planning closure.

Are birds in a chimney protected by law?

Are chimney swifts protected? Yes. They're covered by the Migratory Bird Treaty Act, a federal law the U.S. Fish and Wildlife Service enforces. Under that law it's illegal to kill, capture or collect swifts, or to destroy a nest while it holds eggs or chicks. That rules out lighting a fire, blocking the flue or pulling the nest down while the birds are using it.

The Migratory Bird Treaty Act applies to listed birds, including chimney swifts. Other species and circumstances may involve different protections. Do not assume that an animal can be removed simply because it is not a swift; confirm the applicable requirements first.

Timing depends on actual occupancy and the applicable protections, not a fixed wait of a few weeks. If there is an urgent safety concern, contact the appropriate wildlife agency for guidance rather than disturbing or sealing an occupied flue.

Chimney swifts nesting season, and when they leave

Chimney swifts migrate seasonally and use chimneys for nesting or roosting. Local arrival, departure and occupancy vary. Their small twig nests attach to vertical surfaces, but calendar dates alone cannot establish that a particular chimney is empty.

After lawful confirmation that animals and any protected active nests are absent, the appropriate cleaning, inspection and closure can be planned. The needed work depends on deposits, damage and the appliance. A quiet flue does not prove that every animal has left.

If you are interested in swift habitat, ask a wildlife organization about a purpose-designed structure or another suitable arrangement. Do not leave an operating chimney unprotected or alter its cap without checking the appliance and wildlife requirements.

Bats in chimney flues, and Florida's dates

Florida FWC restricts bat exclusion during maternity season and sets conditions for work outside it. Consult its current guidance for the applicable dates, weather conditions and methods before planning exclusion. A calendar date alone does not permit sealing an occupied opening.

An exclusion device must allow bats to leave without trapping flightless young, and removal of the device and final closure depend on the applicable requirements. A qualified wildlife professional should confirm occupancy and the current FWC conditions for the specific project.

An urgent issue during the restricted period calls for contacting FWC for guidance about the specific situation. Do not simply wait while an immediate hazard continues, and do not seal an exit or operating vent in an attempt to confine the bats.

What you can do while the flue is off limits

Leave the fireplace unused while occupancy is unresolved. Do not light a fire, spray chemicals, vacuum the flue or seal openings on your own. Ask the wildlife specialist how to keep animals separated from living areas without trapping them or interfering with another appliance's vent.

Avoid disturbing droppings or nest material. Histoplasma can occur in soil associated with bird or bat droppings, and airborne spores can cause infection. Appropriate cleanup depends on the material and setting; do not dry-sweep it into the room.

If a bat gets into the house, don't handle it with bare hands. The CDC advises seeking medical advice after any possible contact with a bat, including finding one in a room where someone was sleeping, since bat bites can be small and easy to miss.

After they've gone, close the door

Once the wildlife situation is lawfully resolved, confirm who will handle debris cleanup, chimney inspection and any repairs. Specialized wildlife or contamination work may be separate from chimney service. A compatible cap can then be considered with all other entry paths assessed.

If the animals got in through gaps in the crown or the flashing, those get fixed too, since a cap only covers the flue.

Talk to us about your flue guests

Hear activity in the chimney or see nesting material? Leave the fireplace unused and call (352) 675-6366 to discuss a free inspection and the appropriate next step. Wildlife identification or exclusion may need a specialist. Our family-owned business provides written estimates and 10% off first service. Learn about chimney animal removal.