Numb And Numbers

Citizen scientists brave winter chill for a Sask bird census

Black-capped chickadee, photo by Fran Kerbs

Science | by Gregory Beatty

What would you like to find under the tree this Christmas? A shotgun, perhaps, or maybe a rifle? If you’re like me, those wouldn’t be great gifts. But turn back the clock a century or so, and they’d have met with smiles. The proud new gun owners would put on a coat, march outdoors and blast the living crap out of any wildlife unlucky enough to cross their sights.

Strangely enough, this tradition of bird massacre is part of Saskatchewan’s Christmas bird count story.

Michael Williams is an organizer with Saskatoon’s bird count, which happens Boxing Day (Monday, Dec. 26).

“Frank Chapman, who was one of the founders of the Audubon Society, was concerned about the number of birds being killed every year just for fun,” says Williams. “That was leading to a slaughter of birds on a huge scale, and Chapman thought, ‘Let’s do something else for recreation other than shooting birds. Let’s go out and count them.’”

And thus a new, and better, Christmas tradition was born. The first count was in 1900, and the idea grew from there. Last year, 93 counts were held in Saskatchewan.

Citizen Science

Fast forward to 2016 and Chapman’s bird counts have become valuable from a scientific perspective.

“What’s interesting in bird populations is where species breed and where they winter,” says Brett Quiring, an organizer for Regina’s bird count (also on Boxing Day). “That’s when a species spends the most time in any spot. It’s interesting to track migration, but species are in transit then. If you’re going to have a problem with some threat, or human [intrusion], it’s usually going to happen on their breeding or wintering grounds.”

Counts in Regina and Saskatoon have been held annually since the mid-1950s. Year-to-year, lots of variables could impact on a count’s accuracy. But as data accumulates over decades, it reveals larger trends.

“As Regina’s tree cover grows, we’ve been getting more boreal birds wintering here,” says Quiring. “Those include nut hatches, which are now kind of year-round — as are chickadees. Then depending on the year, there are sometimes other finches such as the redpoll, cross-bills, and pine siskin.”

Saskatoon has seen a similar influx of boreal birds through the growth of its urban forest, says Williams. Some are year-round residents, while others breed in northern Saskatchewan and the Arctic, and over-winter in southern Saskatchewan.

Water bird habitat has also been shaped by the city, says Williams.

“Because of the power station on the riverbank, we always have an open channel of water in Saskatoon and that means a lot of ducks stay over,” says Williams. “It’s particularly attractive for the common goldeneye, which is a diving duck. We usually have a flock of 100 to 200. Mallards are fairly common too.

“You never know what’s going to show up,” Williams says. “Last year we had a harlequin duck, which was way off course — but it stayed here and got counted.”

Survival Strategies

In a typical year, the Regina and Saskatoon counts register 35 or so species. Unlike birds that migrate south to escape winter, these stick it out.

How do they do it?

“All most birds are interested in doing in winter is surviving, which means not expending any more energy than they have to,” says Williams. “On a nice winter day, if they’ve had a good feed in the morning, they’ll maybe just sit on a branch in the sun and try to pass the day that way.”

Water birds and raptors find their usual food sources through diving and hunting. For other birds, seeds from trees and grasses, and dried berries, are go-to food sources.

Household feeders are a third food source — and, arguably, another example of human impact on bird habitat. Not all of our impacts have been beneficial (more on that in a minute), but when I asked Williams if feeders posed any ethical concerns by interfering with the natural order in the bird world, he replied, “It may bother a few purists, but it doesn’t bother me.

“I think you have to be realistic and understand that the reason we have so many birds here is because they find food,” he says. “If you’re going to feed them, the important thing is to be reliable. Otherwise, you may get birds that are relying on you, and then you go away for a holiday and suddenly the food is gone and they have to fend for themselves somewhere else.”

Negative Impacts

While boreal birds have thrived in recent decades, other species have suffered, says Quiring.

“As we use up land for [urban] development and as agriculture changes, prairie birds have been generally decreasing,” he says.

Some of those birds, such as the sage grouse and burrowing owl, are even listed as endangered.

Then there’s climate change. Quiring says three decades of relatively mild winters have led to a surge in raptors.

“Because it was so warm and there was so little snow last winter, we had unheard-of numbers,” Quiring says. “There’s a species called a rough-legged hawk that had been counted twice before, and last year there were 44. We also found two types of hawks we’d never seen on a count, and a couple of red-tailed hawks that we’ve had occasionally.”

In Saskatoon, says Williams, climate change has caused a major shift in corvid numbers.

“Before, crows used to move in every spring and drive ravens out. But a few years ago when we had the West Nile virus problem, it killed a lot of crows off and the ravens took advantage of that. So now there are a lot of ravens nesting that we never used to have.”

For more information on the Regina Christmas bird count visit natureregina.ca.