A chance discovery by a group of Invermere birders led to a conservation success for a fledgling bank swallow colony in Invermere, British Columbia.
In the spring of 2022, local birder Greg Scott and his fellow birdwatchers noticed a small colony of bank swallows near a large dirt mound on a District of Invermere-owned lot bordering Lake Windermere. Upon closer inspection, they found nesting holes and estimated that about seven pairs of the swallows were residing there for the breeding season.
Greg, a volunteer with Wildsight Golden’s Upper Columbia Swallow Enhancement Project, reported his findings to project lead biologist Rachel Darvill.
“She came to check it out and agreed it was a great find! She asked me to keep monitoring the site as part of the swallows project, and I’ve been watching it ever since,” says Greg.
Bank swallows are a species at risk, facing near extinction in Canada with an estimated 93-98 per cent population loss over a recent 40-year period. The swallows project, launched in 2021, aims to inventory, monitor and enhance habitats for at-risk bank and barn swallows in the Columbia Valley (between Canal Flats and Donald, B.C.).
The dirt pile on the District of Invermere land is estimated to have been undisturbed since the 1980s, but until 2022 had gone unnoticed as an important habitat for the at-risk species. Rachel reached out to District staff, urging them to protect the hill. Her timing couldn’t have been better; the District had planned to level the dirt pile in preparation for landscaping and future development plans for a park.
Artificial nesting
In October 2023, the pile was cut away to create a more vertical cliff on one side. The mound was also fenced off to prevent human interference, a suspected cause of colony collapse in other nearby areas.
“Bank swallows need very specific conditions to thrive,” Rachel says. “They look for near-vertical cliffs, proximity to water and specific types of substrate for their nests. We worked hard to ensure the dirt pile met those needs.”
District of Invermere Mayor Al Miller says they were pleased to allocate habitat for the bank swallows that had found a home here.
“When we purchased this land, we saw a true opportunity to be able to increase our area for parks, for both our citizens and visitors,” Al says. “That particular bank that was there had become a great nesting home for swallows. So what better in a park than to add a little education as well? By being able to carve off a nice piece of it and protect it for the future, it adds that whole educational piece to the park.”
From 7 to 195
When bank swallows came back north in the spring of 2024, they started to occupy the newly-created cliff.
“By early May of this year, I saw around nine nest holes, and then every time I came back, the numbers just kept going up. By late May, there were 52 nest holes, and by June, it exploded to about 300 (nesting holes). In 2022, there were only seven breeding pairs,” Greg exclaims. “It’s incredible to see the difference after the habitat enhancement!”
The result was nothing short of extraordinary.
“It was a hugely successful project,” Rachel reflects. “We spent some hours observing the colony, trying to count the number of active burrows. It was challenging due to the sheer volume of activity—there were so many swallows coming and going.”
Rachel and her team determined that at least 195 of those 300 nesting holes were active and produced chicks. With each burrow holding an average clutch size of three to four eggs, upwards of 800 chicks may have been produced at the colony this year.
This project is a testament to the power of collaboration and community-driven conservation.
“We’re not aware of another enhancement project like this one,” Rachel says. “It’s an innovative, collaborative and successful effort for a species at risk, and I hope we can continue to share its success with others.”
Thanks to volunteers like Greg working alongside Rachel in this five-year project, a colony of bank swallows now thrives, a reminder of how small conservation efforts can lead to significant results.
