The chimney swift is a disappearing bird that originally nested in hollow old-growth trees. After those forests were logged, it found a creative solution — it moved into chimneys in human cities.
But now it faces a new housing crisis. Thanks to modern heating technology and regulations, many chimneys are being capped, demolished or modified with a metal liner that makes them unsuitable for swifts.
And now, efforts to protect the bird are bumping up against efforts to ease the housing crisis for people.
Municipal councillors in Leamington, Ont., as well as Toronto-based affordable housing provider WoodGreen, have run into this paradox over the past year — and in both cases learned that preserving swift habitat can lead to higher costs for housing providers.
In Leamington, about 55 kilometres southeast of Windsor, Ont., council wanted to demolish a school and use the land for “attainable and affordable housing.” But because the school had a chimney where swifts were nesting, it required the approval earlier this month of a $640,000 plan to build a new home for the birds.
As Mayor Hilda MacDonald told CTV News, “You could build a pretty nice home” for the cost of the swift habitat.
“You could house some people who are facing housing precariousness with an expenditure like that,” she said. “And here we are building a place for birds?”
But conservation advocates say creative solutions have benefits for both the birds and their human neighbours.
Neighbours under threat
If you live in an urban area from Manitoba east to Nova Scotia, there’s a good chance you’ve heard chimney swifts as they flit high overhead in the evening while hunting insects, says Allison Manthorne, aerial insectivore conservation strategist for the non-profit group Birds Canada.
“They make this really unique kind of ‘chittering’ sound,” she said, noting that most people don’t know what species they’re hearing. “So although they’re ubiquitous across the landscape in Eastern Canada, they’re just really not well known.”
They spend most of their lives high above us, beaks open, gulping insects that make up “aerial plankton.” Manthorne likens them to baleen whales in the sea.
Chimney swift populations have fallen 90 per cent since the 1970s. They’re listed as threatened with extinction both federally and provincially across their Canadian range.
Manthorne, who is based in Sackville, N.B., said that’s mainly due to a decline of the insects they eat and the loss of their own habitats for nesting and roosting — typically, chimneys.
What it means for chimney owners
The birds are protected under both species-at-risk laws and the Migratory Birds Convention Act. If swifts are found nesting in a chimney, the building owner needs a federal or provincial permit to alter it.
To get the permit, they might need to maintain the chimney, build a new one “or find equivalent habitat elsewhere,” nearby, Manthorne said.
Both Leamington council and WoodGreen needed to find alternative swift housing that was located within two kilometres and was at least as tall as the original nesting sites.
WoodGreen’s property was a century-old church with three chimneys in Toronto’s east end.
When the congregation had trouble affording upkeep, they worked with WoodGreen to find a solution. They decided to demolish and redevelop about two-thirds of the building into 50 units of affordable housing for seniors, while retaining the facade and some space for the congregation, said Darlene Cook, WoodGreen’s director of growth and development partnerships.
At a community meeting about the plan, a resident informed them that swifts were nesting in the church’s chimneys.
An investigation by consultant Beacon Environmental found a total of seven birds in the chimneys — two nesting pairs and some “helpers.”
Coincidentally, Geoff Cape, the CEO of WoodGreen’s builder, The Assembly, was also the founder and CEO of Evergreen, a non-profit that runs a community and park space called Evergreen Brickworks.
It is located at a nearby former quarry and brick factory, which once had four tall brick chimneys, each bearing one of the words in “Don Valley Brick Works.”
One, bearing the word “Valley,” remains. It stands 26 metres high in the middle of a children’s garden featuring edible plants like corn and squash, a brick pizza oven, a water cistern and a pump. Cape proposed the chimney as a possible replacement for the soon-to-be-demolished church chimneys, Cook recalled.
Lois Lindsay, chief program officer at Evergreen, said the chimney had been deteriorating for decades and was capped in 2008 to protect it from further damage. Evergreen knew the chimney was a potential swift habitat and wanted to restore and uncap it but “we really didn’t have the money.”
Luckily, given its obligations, WoodGreen paid for the full chimney restoration. It could not provide an estimate of the specific cost, but said the money came out of its $19.8 million budget for the affordable housing project, funded by the City of Toronto through the federal Rapid Housing Initiative.
Benefits for birds… and people
Evergreen’s chimney was uncapped this spring and has been monitored by Beacon Environmental.
Beacon’s CEO and senior ecologist Brian Henshaw said a number of chimney swifts have already been spotted circling above the chimney and diving down as though about to go in. That’s a “good sign,” he said, since the birds usually “check out” a nesting site for a year or two to ensure it’s stable and predator-free before nesting in it.
He added that the Evergreen Brickworks chimney has the potential to do more than the two short chimneys it replaced. While short chimneys are suitable for nesting, the taller chimney has the potential to be a “roosting site” where dozens or hundreds of birds can rest. Swifts must roost in chimneys because their foot anatomy makes it impossible for them to perch in trees.
WATCH | Hundreds of swifts will funnel into a single chimney to roost overnight:[MEDIA]
Evergreen Brickworks has already put up interpretive panels about the swifts at its children’s garden. “We are super excited to incorporate chimney swift education and programming … and can’t wait to welcome the swifts back,” Lindsay said.
As for WoodGreen, its partial demolition of the church is complete and it hopes to finish construction of its 50 apartments in the spring of 2026.
Meanwhile, despite some grumbling, Leamington’s council approved a plan to build three free-standing artificial chimneys to replace the school chimney — one 15 metres high like the original chimney, one four metres high, and one 5.5 metres high. They’ll be clustered along a trail with some benches, greenery and signs about the swifts. “It could lead to some education, give the community someplace to visit,” Robert Sharon, Leamington’s director of infrastructure services, told council.
He added that if swifts end up using the smaller chimneys, that could loosen future requirements and make accommodating swifts easier and less expensive.
Manthorne said the challenges faced by Leamington and WoodGreen aren’t unique. Up until recently, there was a successful federal chimney swift restoration fund, which helped with the cost of building and restoring structures such as chimneys — costs that typically range from $5,000 to $130,000.
Although there is a waitlist for funding, Environment and Climate Change Canada had not yet decided as of this week whether to renew it.
Manthorpe said some situations can look like a conflict between housing birds and housing people, but noted that both housing and biodiversity crises exist.
She added that people benefit from protecting biodiversity — including swifts, which share our cities and eat a lot of insects.
“So they’re providing pest management. They’re really a joy for a lot of people,” she added. “I think it’s really important, especially now, to really consider how we can coexist with nature and how we can solve these problems collaboratively instead of [it] just being an us-versus-them problem.”
