©Wikipedia

Nettie and Thomas Rempel-Ong had uninvited guests living in their 91-year-old home in Winnipeg’s Old Tuxedo neighbourhood — chimney swifts, a migratory bird species classified as threatened under the federal Species at Risk Act. …Chimney swift populations have declined 88 per cent since 1970. How a bird became reliant [chimneys] has to do with European settlement, urbanization and forestry. Pre-colonization, chimney swifts in North America nested in old growth leafy trees, often dead or dying, with hollows large enough to raise a family in during the summer months. …Logging and land-clearing for housing and agriculture eliminated much of their historical habitat. …And the style of chimneys that swifts became reliant on fell out of fashion architecturally. …Chimney swifts are part of the second-most at-risk group of birds in Canada, called aerial insectivores. …they feast on insects in flight, including mosquitoes and beetles, the latter of which have experienced declines associated with DDT pesticide use.