Mon February 24, 2014
For Michigan Birds, Cold's OK, Snow's Sometimes Not
Lisa Duke stands by a lake at the Kellogg Bird Sanctuary near Augusta. A variety of birds stand near the shore: mallard ducks, Canada geese and, much taller than everyone else, trumpeter swans. With mating season on the way, Duke says they’ve got moves to practice.
"The newer pairs, they do this head bob in unison. So they keep practicing their head bobs and calls together and it kind of reinforces that pair bond," she says while swans trumpet nearby.
Duke says the cold – even extreme cold – isn’t in itself a problem for Michigan’s native bird species that stick around during the winter. They come with the finest down coats. Their circulatory system keeps their feet warm despite the lack of feathers. And they’re good at saving energy.
"They can switch their metabolism and slow it down a little bit," Duke says.
"So when it’s really really cold, those negative degree days that we had, they barely even moved. They would just kind of hunker down, tuck their feet into their feathers, tuck their heads and bills underneath their wing and just keep as much warmth in as they could."
Call it the ball-of-feathers technique.
But Duke says even if the birds are well-adjusted, this winter’s extreme conditions have called for some unusual adaptations. The birds at the Sanctuary stayed closer than usual to their food and open water.
"In my previous winters here like that didn’t happen," she says. "They would move around through the state and they would disappear for a couple days and come back later. But most of the time they’re just – they’re just here."
At the Kalamazoo Nature Center north of town, John Brenneman and Kyle Bibby have also seen birds adapting to the conditions.
They stand near a couple of outdoor enclosures. One houses two red-tailed hawks; the other, a great horned owl.
These some of the center’s raptors, or birds of prey. Most came here after run-ins with cars that left them unable to make it in the wild. Brenneman says because of their injuries, they can’t always cope with the cold.
"I think we’ve had to take them in three times," he says.
"And they usually put them in little bins and put them inside or, not inside but in a protected area from the cold with the subzero temperatures. Once it gets below zero and the wind chills get really cold. A lot of the birds can take that temperature but they don’t have the mobility that a wild bird does. And some of them are missing wings and things like that. So they can’t insulate themselves as well as a wild bird could," he says.
He adds that this winter, even uninjured raptors have likely struggled to find food.
"The raptors that are going after mammals would have a little harder time because with the depth of the snow it would be harder to find mice and other things of that sort. And we’ve had some reports of red-tails found dead and things of that sort. I’m guessing those are young birds, probably," he says.
For other birds, like ducks, the challenge has been finding water that isn’t covered by ice. Lake Michigan has frozen further into its center than usual. And many smaller lakes are completely ice-covered, leading birds to seek water elsewhere.
The state Department of Natural Resources wants people to watch out for stranded water birds, including grebes, which look a bit like ducks.
"Grebes will come in and they see wet cement something of that sort, come down to land on it thinking it’s water, and then they can’t get off of it... because they kind of need a running start to get up in the air. And when they’re not on water that’s impossible for them to do," says Brenneman.
The conditions have led to some uncommon sightings in and around Kalamazoo.
"In this last week down on the Kalamazoo River we’ve gone down a few times and there’s been some white-wing scoters and long tailed ducks down there and that’s a pretty unusual species. Probably less than fifty records of them in Kalamazoo County in the last hundred years," Brenneman says.
At the Kellogg Bird Sanctuary, Duke says she hasn’t seen too many birds out of place.
"We’ve had a few bald eagles, which is always exciting for us, that have been probably moving because the lakes that they were hunting on were freezing," she says.
Nature Center Research Coordinator Kyle Bibby says many people have called to report sightings of robins and bluebirds, wondering why they’re back so early.
"That’s not really so much because the winter has been harsh but because the fall had a really productive fruiting season," Bibby says.
While many robins head south in winter, Brenneman says some always stay. Even more stayed this year because of the berry bounty. But they’ve likely eaten most of what they can find in the deep woods by now. That means they’re coming back out to look in neighborhoods.
And if you’ve heard more birds singing the past couple of weeks, Brenneman says you’re not imagining things. As the days start to get longer they sing regardless of whether it looks it’s going to warm up.
"I’ve heard cardinals doing their little spring songs and the chickadees and things," Brenneman says.
"It seems like we get a little more sun this time of year too. So I think the birds are just happy that there’s some sun and it’s a little warmer temperatures and they’re singing and getting ready for spring here soon."
At the Bird Sanctuary, Lisa Duke says she’s noticed those patterns change too. "It gives you hope that the snow will eventually disappear," she says.
Maybe then the swans will venture further than the lake.