New spruce grouse survey gives DNR a window on tough-to-monitor birds

Minnesota researchers have a new way to monitor populations of spruce grouse – a bird species that’s notoriously difficult to count – through an annual spruce grouse survey that happened for the first time in the spring with help from dozens of cooperators and citizen volunteers.

Spruce grouse are a game species in Minnesota, but in neighboring Wisconsin they are listed as threatened. As a species dependent on conifer forest habitat, they are expected to have a smaller range in the future because of climate change induced habitat loss.

“We needed better information about the population to make informed management decisions,” said Charlotte Roy, grouse project leader with the Minnesota Department of Natural Resources. “This survey is expected to detect meaningful changes in the population over a 10 year period.”

DNR researchers spent four years developing a survey methodology for the difficult-to-survey spruce grouse. Cooperators, citizen volunteers and DNR staff count grouse signs (droppings) at spruce grouse sites. By conducting the survey annually, researchers can detect meaningful changes in the population.

Before this survey, the only data the Minnesota DNR collected on spruce grouse were the estimated total of birds harvested by hunters as part of the annual small game harvest mail survey. That survey estimates the total harvest of spruce grouse at 10,000 to 27,000 birds per year since 2006; however, spruce grouse harvest is not a reliable way to track population trends.

“Citizen-scientist volunteers and cooperators are important contributors to the survey. We couldn’t do this survey without their help,” Roy said.

Last spring, cooperators at Chippewa National Forest, Grand Portage Band of Lake Superior Chippewa, Leech Lake Band of Ojibwe, Red Lake Band of Chippewa Indians, 1854 Treaty Authority, DNR Wildlife, Superior National Forest and 40 citizen-scientist volunteers including Vermilion Community College students, surveyed 65 routes throughout the northern conifer forest region of Minnesota.

Spruce grouse sign was found at 88 sites representing 32 percent of those surveyed. More sign was found in the northwest portion of the survey region, followed by the northeast and then the southcentral portion. The survey will be conducted annually to track population trends and changes in distribution.

The DNR’s 2018 spruce survey report and grouse hunting information can be found at mndnr.gov/hunting/grouse.