What Do Sage Grouse Do All Winter?
February 1, 2017
Sage grouse are tough birds, surviving cold winters in western North America. Photo Stan Harter.
Ask An Expert: Tom Christiansen, Sage Grouse Program Coordinator for Wyoming Game and Fish
Lots of birds head south for winter. Do sage grouse migrate, too?
Many sage grouse do migrate, though some stay sedentary. Migration often depends on how much snow the local landscape receives. Sage grouse typically move from higher to lower elevations to avoid deeper snow.
For instance, in Idaho, a population might migrate from a high-elevation mountain valley to the desert floor. And on the border of Montana and Canada, researchers have documented one population that moved 150 miles in response to winter conditions, the longest known migration route for greater sage-grouse. But that distance is more the exception than the rule.
Sage grouse migrate more like big game species than other bird species. Like elk or deer, sage grouse move in the tens of miles as opposed to the thousands of miles traveled seasonally by songbirds or waterfowl.
Do the birds band together or stay solo in the snow?
They do flock together in the winter, and its not uncommon to see flocks of several hundred birds. Joining forces is a behavioral adaptation among many species — when you have lots of eyes and ears together, it’s easier to avoid predators.
But, unlike a bobwhite quail or other bird species, sage grouse don’t huddle up in a covey to use each other’s body heat. Instead, if conditions are really harsh, they’ll burrow in the snow, or use tall sagebrush for cover.
What are sage grouse looking for in a winter home?
First, the birds need sagebrush plants that are exposed above the snow. Sage grouse eat 100 percent sagebrush leaves in the winter. They need to fill their crops – the food storage sack in their throat — full of leaves every day. Their crop is a little larger than a golf ball when it’s full.
Second, the birds need to be relatively undisturbed. Sage grouse will flush if disturbed, which uses up their stored energy reserves as they fly away from perceived danger.
The third component of good winter habitat is having access to large expanses of sagebrush — postage stamp habitats don’t work if you want a healthy, successful sage grouse population.
Are sagebrush leaves tasty?
Not to us! They’re actually toxic, full of harsh chemicals called terpenoids — the same basic chemical found in turpentine. Sage grouse have unique digestive systems that allow them to remove the toxins and excrete them separately as a cecal dropping that looks like a silver-dollar-sized drop of tar.
But the leaves are plenty nutritious, which is why sage grouse tend to gain weight in the winter months, unlike most animals.
Do they move around during the winter or stay put in the same place?
Just like nesting and lekking habitats, sage grouse have high fidelity for returning to the same general wintering grounds. However, they do pick up and move, sometimes as often as daily, depending on snow depths and access to sagebrush. That’s why, once again, it’s so important that the birds have large, intact sagebrush landscapes to travel in and around.
How do they survive in some of the coldest, harshest climates in North America?
The bottom line: sage grouse are tough! They’ll use windswept ridges if that’s where sagebrush leaves are exposed.
Sagebrush is great shelter in and of itself, providing wind and snow blocks for the birds and other small animals. From their perspective, sagebrush is a forest.
Winter isn’t a problem as long as sage grouse get plenty of sagebrush leaves to eat. But occasionally if you have a bad winter with sagebrush covered completely for long periods of time, you can have mortality.
How can we help protect sage grouse winter range?
It’s important not to remove sagebrush, first off. Or to disturb the birds, especially since they flush more easily in winter when living in larger flocks.
And just like the rest of the year, sage grouse need access to vast, intact landscapes. Across the West, including here in Wyoming, we partner with ranchers to protect privately-owned sage grouse habitat, ensuring that the birds have the food and cover they need year round.
Meet The Expert
What’s your role with Wyoming Game and Fish?
I coordinate biological data collection and reporting from biologists across the state, administer the eight local sage grouse working groups in Wyoming, and work with my peers in other states to coordinate sage grouse and sagebrush community management across the range.
I’ve been with the agency 32 years, 20 as a field biologist and 12 administering the sage grouse program.
In your free time, where can we find you?
Doing the usual stuff: hunting, fishing, hanging with my bird dogs, or playing with my granddaughter.
The Sage Grouse Initiative is a partnership-based, science-driven effort that uses voluntary incentives to proactively conserve America’s western rangelands, wildlife, and rural way of life. This initiative is part of Working Lands For Wildlife, which is led by USDA’s Natural Resources Conservation Service.