A better way to sample ruffed grouse? DNR explores whether brood survey can better predict hunting prospects
This year, 52 observers from across Minnesota’s ruffed grouse range – all wildlife and natural resources professionals – provided brood count data.
GRAND RAPIDS, Minn. – It’s still a work in progress, but the Minnesota Department of Natural Resources is exploring whether a brood count survey for ruffed grouse would give hunters a better idea of what to expect as far as fall hunting prospects.
The survey would supplement the drumming counts that DNR staff conduct each spring with help from other cooperators, including Native American tribes and other natural resources agencies.
Historically, the drumming count survey has been the only tool for DNR wildlife managers to sample ruffed grouse because the forest habitat where they live makes them difficult to count. As part of the survey, staff drive predetermined routes and listen for the drumming sound male ruffed grouse make as they rapidly beat their wings in an effort to attract a mate.
For the past couple of decades, though, the drumming count surveys haven’t correlated very well with fall conditions, said Charlotte Roy, grouse research scientist for the DNR in Grand Rapids, who is coordinating the brood count survey.
There could be a variety of reasons for that, Roy says, including West Nile virus and climate change, both of which could have a negative impact on nesting and brood success.
“Since 2019, we’ve been attempting to see if we can get a better handle on the fall forecast,” she said. “And so the brood count survey we’re exploring – and I would say exploring is the right word – is just to try to see if we can get a better handle on what the fall forecast would be for hunters.
“A lot of people travel from out of state and travel long distances to hunt ruffed grouse, and so that’s a piece of information that hunters enjoy having.”
In developing the survey, which now is in its fourth year, Roy initially asked the cooperators in the spring drumming count survey if they would be willing to keep track of their time in the field, both on foot and while driving, and indicate whether they saw – or didn’t see – ruffed grouse broods.
“It’s important to also include observations of when people don’t see broods because it gives us an indicator of the amount of effort that’s going in,” Roy said. “If people only tell us when they see broods but don’t tell us when they don’t, that would inflate our estimates.”
Since the initial survey, the brood count study has expanded to include personnel from different sections of the DNR and even private foresters, Roy says. This year, 52 observers from across the state’s ruffed grouse range – all wildlife and natural resources professionals – provided brood count data.
“They basically are keeping – it’s like a diary of, ‘I spent this much time in the field today in the forest, and I didn’t see anything. Or, this is what I saw,’” Roy said.
The numbers are compiled by county during June, July and August, after which Roy summarizes the data and writes a report.
Ideally, the results would document patterns between what observers see in the field and what hunters encounter in the fall. So far, though, the results are mixed, Roy says.
In 2021, for example, widespread spring and summer drought created ideal conditions for strong ruffed grouse production, Roy says, and anecdotal reports from hunters indicated they generally were happy with hunting success last fall.
However, results from a mail-in survey of small game hunters conducted by other DNR staff indicated ruffed grouse harvest statistics last year were similar to the previous two years, Roy said. The average ruffed grouse harvest has hovered between 3.5 and 3.7 birds per hunter since 2019, when she started exploring the brood survey.
That’s “really not very much” variability, Roy says.
“To date, those harvest statistics are staying pretty much the same, even in years where we have strong production like last year,” she said. “We saw good numbers in the brood survey, but then it’s not really reflected in the harvest statistics.”
Based on this summer’s counts, counties in northeast and north-central Minnesota, including Hubbard, Cook, Itasca, Lake and St. Louis, had the best ruffed grouse production, as measured by the number of broods seen “per unit of time out in the field, either on foot or while driving,” Roy says. Other counties that will be included in her report are Becker, Beltrami, Carlton, Cass, Crow Wing and Koochiching, she says.
Counties must have at least 100 hours of observations before Roy includes them in the report.
Time will tell, Roy says, whether counting broods ultimately proves a reliable indicator of fall ruffed grouse hunting prospects. First, she’ll need a few more years of data.
“I do hope so,” she said. “My goal is to come up with a useful product. But if we’re just finding that it’s not predictive, then the answer will be no because we don’t want to just put something out there that’s not very useful.”
Despite the uncertainty, Roy says she believes the brood count has potential. Studies have shown that up to 70% of the ruffed grouse that are harvested in a particular fall are from that year’s hatch, she says.
“If we have a poor production year, that can really impact what hunters see and experience in the fall, and so I’m very hopeful that we’ll be able to get something meaningful out of this,” Roy said. “But I do want to make sure that it’s going to be meaningful before we have people anticipating a release of the information.”