Natural resources officials look for possible explanations
By Eileen Persike
A decline in Wisconsin’s ruffed grouse population could mean a shortened hunting season this fall. Grouse drumming surveys, which are used by the Department of Natural Resources to track long term trends, have fallen by 34 percent statewide; 38 percent in the northern part of the state. Mark Witecha, an Upland Game Ecologist for the DNR, said grouse follow a fairly predictable 10-year population cycle in the Northwoods, with the next peak expected in 2020 and numbers increasing until then.
“The decline was unexpected, but confirms what we heard from some hunters last fall,” Witecha said. “There is no scientific evidence of factors that led to the decline. There is some suspicion that West Nile virus could have been a factor.”
The population decline could be due to multiple factors and to provide potential benefits to the ruffed grouse population, the Wisconsin Conservation Congress recommended to the Natural Resources Board in June that they issue an emergency rule to shorten the season by two months. For Zone A, which includes most of the state, that would mean a grouse-hunting season from mid-September through the end of November. The NRB will take the subject up at its Aug. 8 meeting.
Research in the northeastern part of the country may suggest that West Nile has impacted grouse populations there. But Witecha said he would urge caution when applying scientific results from Pennsylvania to Wisconsin, saying, “Our population is considerably healthier and we have more habitat for ruffed grouse in this state.”
With West Nile a potential concern, the Wisconsin DNR is working collaboratively with its Minnesota and Michigan peers and the Ruffed Grouse Society to monitor the population over the next three years. There has been no confirmation of the disease in Wisconsin grouse, Witecha said, but the DNR is “ramping up efforts to collect samples and get a baseline for West Nile prevalence in ruffed grouse.”
Additionally, the current interest in ruffed grouse is an opportunity to begin a Grouse Management Plan and take a holistic view of the game bird.
“It will help spell out population objectives, goals for the coming years, give us a snap shot of what the population currently looks like and allow us, allow the public to ask questions that we’ve been looking for answers to, such as proposing new research,” Witecha explained.
As for shortening the hunting season, Witecha said research on upland game birds shows that may not help the population because the birds are short lived; 70 percent of the population dies in a single year regardless.
Testing kits will be available in the fall so hunters can send grouse samples in for testing. In the meantime, Witecha is encouraging anyone who is out in the woods and sees sick or dead birds, to report it to a DNR biologist. For more information, or to comment on the topic, visit dnr.wi.gov/about/nrb.