Minnesota hunters, biologists seeking answers to lackluster ruffed grouse season
Grand Rapids, Minn. — When the DNR announced last July that spring ruffed grouse drumming counts had increased 57 percent statewide, hunters were understandably giddy at the prospects of what they’d encounter in the woods during the fall.
The season began slowly, which isn’t unusual when there are a lot of leaves on the trees. Then the leaves fell, but things didn’t pick up. At that point, the poor reports were anecdotal.
Then the Ruffed Grouse Society held its annual national hunt in the Grand Rapids area and it quickly became apparent that something was amiss.
“It was unprecedented that we had spring drumming counts that were that good and hunting success that was that poor,” said Ted Dick, ruffed grouse coordinator for the DNR.
An avid grouse hunter, Dick was no exception.
“My hunting was pretty miserable, really,” he said. “I was excited about it, but it was just kind of a bust compared to the flush counts we expected to get.”
While he heard good reports from hunters around the firearms deer season and during December, “There’s no question the number of flushes and success for the majority of people during the prime time of October was less than expected,” Dick said.
During the 36th annual RGS National Grouse and Woodcock Hunt, which was held Oct. 12-13 and during which 108 hunters killed 124 grouse, the harvest was down about 30 percent, and the number of young birds in the bag “was the lowest in the history of the hunt,” Dick said. “It doesn’t usually work that way. There’s usually a pretty good correlation between the drumming count and fall success.”
When high drum counts don’t lead to good hunting in the fall, the blame often is placed on bad weather – cold weather and precipitation – in early June when the chicks are young. But that doesn’t appear to have been the case in 2017.
“We’ve been looking at that lately and we really didn’t have poor weather then,” Dick said. “It wasn’t cold. The temperatures were average or slightly above, and precipitation was in the normal range, too.”
So why was the 2017 season so far below expectations?
“We are still curious as to why that happened,” Dick said. “I would be curious to know if that lower recruitment was because young grouse were susceptible to some type of mosquito that could spread West Nile virus in early June. We saw lots of young birds in the woods in the spring, but they didn’t seem to be around in the fall.”
DNR wildlife researchers are discussing the possibility of conducting a pilot-type study to try to assess whether – or to what extent – West Nile virus is affecting grouse in Minnesota. A final decision to move ahead with such a project – which likely would involve collecting blood samples from hunter-harvested grouse – hasn’t yet been made.
“It’s something we really haven’t looked at,” said Michelle Carstensen, DNR wildlife health program leader.
The virus has been present in the state for more than a decade, but there’s little known about its effects on upland birds. Some birds, such as crows and blue jays, die each year from West Nile, while it appears to have little effect on others, including robins.
Other states, however, have documented grouse dying as a result of West Nile. Michigan, for example, has had West Nile since 2002. That state’s DNR last year issued a news release announcing five ruffed grouse for the first time in the state had tested positive.
The Michigan DNR release also noted researchers in Pennsylvania have studied the effects of West Nile virus on grouse, but that there isn’t a clear consensus on the role it might play. In Pennsylvania, researchers have collected wild grouse eggs and infected the chicks with the virus. Many of those infected chicks died or suffered organ damage, according to the release.