The Chimney Swift... coming to a chimney near you

Chimney Swift nest stuck to the inner wall of a hollow tree and showing a curved shape of dried saliva on the wood above the nest. Photo: Patrick Labonté © Environment CanadaThe summer skies over our cities and countryside would be less lively without the zany aerobatics and joyful chirping of these small, dark-coloured birds. All can enjoy watching Chimney Swifts. The onlookers are treated to a real performance by the birds at dusk, when an entire flock will swoop and swirl for a while above a chimney before settling inside for the night. The bad news is that the Chimney Swift’s population has plummeted in recent decades to the point where it is now designated as threatened in Canada. The good news is that you can help.

What are Chimney Swifts?

Map of the Americas showing the species distribution. © Serge Beaudette The Chimney Swift nests in dark places, safe from predators and inclement weather. Before Europeans arrived in North America, the bird used to nest in large hollow trees and, sometimes, in rock crevasses. For decades now, however, the Chimney Swift has usually built its nest in stone or brick chimneys, which is how it got its name.

Each spring, the Chimney Swift arrives in Canada between late April and early June to breed. Chimneys are used initially as collective roosts. Pairs then disperse to nest, with one pair per chimney, with their nest glued to the inner wall.

The nesting period lasts from mid-May to mid-August. Both parents share responsibility for incubating the eggs and feeding the chicks. Once the young are independent, the family can return to a collective roost during the night. The Chimney Swift leaves for its wintering grounds in South America between early August and early October.

Ravenous appetite and boundless energy

The Chimney Swift is an insectivorous bird with an insatiable appetite and tireless energy. Have you ever seen one perched? Surely not, because it spends its days on the wing catching insects. A single Chimney Swift can consume over a thousand insects a day without ever coming to rest.

Besides, even if it wanted to perch, it could not. As its family name -- Apodidae, or feetless -- suggests, the Chimney Swift has very short feet that prevent it from walking or perching horizontally like other birds. It can only perch vertically.

Easy to recognize

A flying Chimney Swift showing the characteristics of the species in flight: long curved wings and short tail. © Serge Beaudette The Chimney Swift makes its presence known in the skies: the high-pitched chirping of its incessant chatter is all the louder because the bird rarely flies alone. Its long, narrow, pointed and curved wings make it look like a little boomerang -- a boomerang, however, without any sense of direction, as it zooms and zigzags at top speed, constantly changing its direction.

Unlike swallows, for which they are sometimes mistaken, Chimney Swifts can be distinguished by their streamlined body and very short, non-forked tail.

Serious problems

Eyes still closed and feathers beginning to grow, three nestling Chimney Swifts in a nest that is stuck to the inner wall of a brick chimney. © Paul and Georgean Kyle, Driftwood Wildlife AssociationThe Chimney Swift, which was once very common in populated regions of Quebec, is now in serious trouble. Between 1968 and 2004, the number of individuals fell by 95% in Canada. This is why the bird is now legally protected as a threatened species.

Chimneys that swifts can actually use are increasingly rare. Many traditional chimneys have been destroyed or are equipped with a cap that blocks access, and fewer new chimneys are constructed because of electric heating. In addition, the interior diameter of most of these chimneys is now too small (under 30 cm), and the interior wall is made of metal, so the bird cannot use it for roosting or nest building.

Should this species return to hollow trees to compensate for the loss of suitable chimneys? Some individuals may, perhaps. The problem is that deforestation over the last two centuries has significantly reduced the number of suitably large trees.

Lastly, in addition to habitat loss, the insect populations that provide food for the Chimney Swift have also changed. Insecticides are considered the main cause.

Swifts at La Vieille École – A personal story

La Vieille École, a bed and breakfast in Grandes-Piles in Mauricie, and the owner, John Graham, pointing at the chimney through which Chimney Swifts enter. © Stéphane Carbonneau
I bought this property to turn it into an inn. I had to do a lot of renovations, especially to the chimney, but when I learned that a bird species that is threatened in Canada was nesting there, I changed my plans to protect the swift pair. Today, I’m happy to know that these birds are still nesting in my chimney. Better yet, observing the birds is now an activity I offer to customers at my inn.

John Graham,
owner of La Vieille École,
a bed and breakfast in Grandes-Piles
in Mauricie

Don’t worry…

A Chimney Swift nest will not damage your chimney and is not known to cause fires or pose health risks.

Legal protection

The Species at Risk Act protects Chimney Swifts by prohibiting people from killing, harming, harassing, capturing or taking the birds. It also prohibits the possession, collection, buying, selling or trading of an individual or parts of an individual, or the damaging or destruction of its residence. The Chimney Swift is also protected by the Government of Canada’s Migratory Birds Convention Act, 1994 and the Migratory Birds Regulations, which prohibit the harassment or killing of juvenile or adult migratory birds, as well as the destruction or disturbance of their nests or eggs.

You can help and be proud to shelter a species at risk

If your residence can accommodate swifts, you can help the species recover.

  • Learn more about the species by visiting the Species at Risk Public Registry.

  • Keep the opening to your chimney free of any obstructions. Grills and caps should be avoided.

  • If your chimney has previously been used by swifts, keep it, even if it is no longer used for heating.

  • Consider the possibility of keeping trees on your property that could meet the swift’s needs, particularly if the tree trunks are hollow, which is often the case for trees with their tops cut off.

  • Reduce your insecticide use to a minimum.

  • If you notice swifts in your chimney, notify Regroupement QuébecOiseaux, which manages the SOS-POP database (Suivi de l’occupation des stations de nidification des populations d’oiseaux en péril du Québec). Doing so improves our knowledge of the species and allows us to better plan its recovery. You can report your observations using an electronic form online.

  • To get help or advice, or to become involved in protecting the species, contact conservation organizations in your region.
Drawing of a Chimney Swift being chased out of a chimney by a chimney sweep brush., collection: Dorling Kindersley

During the nesting period, which runs from mid-May to mid-August, do not have your chimney cleaned.