Breeding burrowersBringing back BC’s burrowing owls
Juvenile burrowing owls (Photo by Lauren Meads)
Standing at under a foot tall, with a wingspan of just 24 inches and long legs holding up a feathery, football-shaped body not much bigger than a beer can, the burrowing owl is a grasslands raptor whose curious habits (and piercing yellow eyes) make it an endearing, but perplexing, species. It breeds well in captivity, tolerates the volunteer humans who work to re-introduce it to British Columbia's interior, and likes to spread its wings on annual migrations south — from where it might decide not to return.
While a few populations thrive in Washington state and Oregon, burrowing owls were declared extirpated in British Columbia in 1980. The population had fallen by up to 90 percent over the past century, a victim of development and predators. When the BC government tried to reintroduce burrowing owls by releasing them into the wild in the late 1980s, the owls just wouldn't burrow. It wasn't until 1990, when a dedicated group of volunteers began a captive breeding and reintroduction strategy, that the current reintroduction efforts took off.
Breeding baby owls
Juvenile burrowing owls are raised in captivity and released into the wild. (Photo by Lauren Meads)
Across BC, there are three breeding facilities where pairs of "founder" owls from Oregon and Washington demonstrate that one thing burrowing owls do well is breed in captivity. They mate, hatch nine to 10 owlets at a time and even put up with researchers banding their legs and checking their wings for feather damage or mites before they are introduced to the wild at one year old.
Ordinarily, burrowing owls occupy empty gopher or marmot tunnels, using the pre-existing structures and doing some renovations of their own to create their nests. They're able to dig a bit, explains wildlife biologist Lauren Meads, but they prefer to move in to established neighbourhoods. Meads, who works for the Burrowing Owl Conservation Society of BC, spends a lot of time scoping out safe and secure nesting sites across the BC interior.
The sites need to be grassy and open, as burrowing owls can't live where there are lots of trees, and they need to have plenty of small animals like mice and voles for the owls to eat during their eight- to 10-year lifespan. It's the kind of landscape easily found in on lands protected by the Nature Conservancy of Canada such as the Sage and Sparrow grassland near Osoyoos, BC, as well as on several wildlife management areas and even private ranches throughout the interior.
A drainpipe makes a great substitute for a marmot tunnel. (Photo by Jim Wyse)
In the absence of natural nesting tunnels on the land, volunteers construct burrows, digging into the earth to install PVC drain tubing that leads to overturned black plastic buckets that create nesting dens. The buckets are sunk into the ground, and have lids that can be opened by biologists when they check on the owls. They're designed to keep the owls safe from predators like coyotes and bears, and to keep ranchers' cattle safe from getting their legs stuck in the nests.
Once yearling owls are installed in pairs in the burrows, they're protected with a hockey-net type of enclosure to give them a chance to grow accustomed to the site. Volunteers and biologists visit the owls for the first few weeks, supplementing their diet with mice or day-old chickens, which can cost up to a dollar each.
Lauren Meads, Jim Wyse and Barb Pryce visit a burrow (front). (Photo by Michelle Dano)
Barb Pryce, the Nature Conservancy of Canada Southern Interior program director, explains that to build a set of burrowing owl dens, it takes a "huge effort and infrastructure development."
The Nature Conservancy of Canada is the country's leading national conservation organization, working in partnership with other conservation groups like the Burrowing Owl Conservation Society of BC. "The Nature Conservancy of Canada has undertaken significant land acquisition in the South Okanagan and Similkameen," Pryce explains.
An estimated 700 burrows have been built across the province over the past two decades, and more are in the works. "We want to continue supporting the Burrowing Owl Conservation Society of BC not only in maintaining the site they have at Badger Flats, but to expand their program by creating a new site at the Sage and Sparrow Conservation Area," says Pryce.
With approximately 100 owls released into the wild every year, it's hoped that there'll be growing evidence of the owls taking over these neighbourhoods. That is, if they don't perplex researchers by deciding to head south instead.
Fly away, baby
The adult burrowing owl’s flight is choppy, with long glides. (Photo by Lauren Meads)
Tracking burrowing owls is tricky, explains wildlife biologist Lauren Meads, who works for the Oliver-based Burrowing Owl Conservation Society. They tend to travel alone rather than in flocks like Canada geese, and can range far and wide every winter when they make their migration south. Banded birds have been reported as far away as Arizona and Mexico. Once they've flown that far, some apparently decide they prefer life in a warmer climate. Over the past two decades, only an average of 14 owls a year have been tracked as returning to their BC nesting sites.
One owl, known as "3 over X" for the labelling on his ankle band, proved himself a snowbird who definitely knew the way to San Jose — the trouble was, he didn't manage to find his way back. A female burrowing owl, released last year at the Badger Flats site that's part of the Nature Conservancy of Canada's Sage and Sparrow conservation area in the South Okanagan, has been located with a mate in Oregon.
In the United States, an organization called the Global Owl Project is trying to learn more about migration patterns using GPS systems and data recorders, but those high-tech tools cost between $3,500 and $5,000 each. And the devices may well end up lost, points out Jim Wyse, a director of the Burrowing Owl Conservation Society. As such, researchers are frequently looking at new ways to gather valuable information about the birds' habits, patterns and lifespans.
While many owls still move south, it appears that the volunteers' hard work is slowly paying off. This past spring, a record number of 50 burrowing owls returned to their home areas in BC, giving biologists like Meads a lot of hope, and a lot more to speculate about. The last winter wasn't as cold in British Columbia, so perhaps they didn't go as far away, and found it easier to return. Or perhaps the hunting was better close to home. Or perhaps they have other reasons, which biologists still don't understand.
Lauren Meads checks an owl’s wing for feather damage. (Photo by Barb Pryce)
Even when the owls don't return to BC, though, they're doing well elsewhere, and thereby helping increase the number of owls in other areas where they're at risk, says Meads. And for now, the key objective is to learn more about these big-eyed, long-legged, underground dwelling raptors, no matter where they roam. "If we can help other populations as well," says Meads, "that's a bonus."
And meanwhile, even though the burrowing owl is still on the endangered species list, this year's return of 50 birds demonstrates that it's regaining much lost ground in BC. Once the population reaches a “sustainable” point of about 10 to 20 breeding pairs across the region, says Meads, researchers will be able to feel confident the burrowing owls have dug in for good.