Pierre Bolduc’s background as an aeronautical engineer and Hercules C-130 pilot wasn’t enough of a resume to prepare him for the task of constructing a pond next to his Alberta property.
He’d made a few attempts to build a dam over several years, but after a downpour washed out his latest earthen structure he turned to nature’s expert dam builders, a family of local beavers, to do the job right.
"There were beavers living further down the valley that had been building dams at a culvert running underneath a dirt road," says Bolduc, who lives on an expansive property near Bragg Creek, about 50 kilometres southwest of Calgary.
"After a beaver-proof culvert had been installed there by the Municipal District of Foothills, I devised a way to lure them onto the desired construction site."
Bolduc reckoned that the gentle lilt of running water played from an outdoor sound system placed above the intended site would attract the animals to the location where he wanted to build the dam. His neighbour, a sound engineer, offered to mix a CD featuring an appropriate aquatic aria.
"I don’t know what the sound of rushing water does to the psyche of a beaver, but based on the results I witnessed, I think it could inspire them to build a dam right in the middle of a sandbox," he says.
"They went straight to work."
Beavers build dams by felling trees with their teeth — poplars are a favourite. The inner bark and soft wood just below the surface bark is considered a choice meal.
They initiate construction by carrying the timber to the site between their teeth, driving logs and branches into the mud of a stream bed to form the base of the dam.
After that, almost anything goes as they use their front paws to complete the superstructure, dragging sticks, rocks, mud, grass, leaves and plants in place to finish the job.
Since labour was being provided at no cost, Bolduc provided them with plenty of free food and construction material. He cleared poplars located on his property that might eventually grow to interfere with power lines. He then placed the cut logs to float in the rising water around the dam construction site.
"I gave them so much wood that they soon developed a 20-beaver condo," he says. "They built an absolutely huge mansion and a powerful dam."
The dam was completed in the summer of 2014 and Bolduc’s pond slowly expanded to a body of water measuring about 175 metres by 200 metres. The pond has since become home to numerous trout and the water has attracted muskrats, nesting loons and moose to the property.
The beaver dam has performed well since, standing up to subsequent heavy rains.
"After a recent significant downpour, water levels went up about a foot, but the dam held nicely," says Bolduc. "For anything that even looks like a breach in that dam, the beaver construction team comes out in force to immediately fix it."
While he’s satisfied with the pond, Bolduc is breaking out his rushing water CD and outdoor speakers for another construction project, courtesy of Castor Canadensis (the North American beaver).
"There are new neighbours along the valley and when I want to visit them, I pretty much have to drive the distance to their place," he says.
"If I place those speakers just right, by next year I should be able to canoe to the neighbour’s house."