Grouse forecast: Good, but not great
That was the peak?
Drumming counts, the most widely used method to estimate ruffed grouse population trends, were down this year in Wisconsin and Minnesota from what now appears to have been a decade high in 2017 — a season that wasn't great in many hunter's assessment.
The 2017 peak was actually higher than drumming peaks in the late 1980s and 90s. But hunting success didn't seem to match. Moreover, this latest peak seems to have crashed faster than in past decades - after just one high year. Minnesota drumming counts dropped 29 percent from 2.1 per mile in 2017 to 1.5 drums per stop this spring. That puts 2018 drumming a little above 2016 levels and the second best year since 2010.
Wisconsin's survey showed a 34 percent decrease statewide from 2017 levels and showed drumming down 39 percent in northern counties. Wisconsin biologists said the crash happened unusually soon after the peak and wasn't consistent with past peaks that stayed close to high levels during past cycles.
The drumming declines don't necessarily mean hunting may be worse on Saturday when the grouse season opens in both states than it was last year, or better than 2016. Wildlife biologists say drumming counts are only an indicator of adult male grouse looking to mate in April and May. The counts don't take into account how many young birds are born and raised this summer.
"Most of the grouse shot in any given year, more than 50 percent, come from that year's broods, so the brood (survival) success is a really big factor. And we just don't know what that is yet," said Charlotte Roy, Minnesota DNR grouse program leader.
It was a wet June in many areas, with flood-spurring downpours in some areas "and that's bad. But it wasn't cold. Cold and wet is the kiss of death for grouse broods," said Tom Rusch, DNR wildlife manager in Tower.
How many young grouse were successfully hatched and survive until Saturday's opening day of hunting depends on many factors, including weather and predators. That means how many grouse you will see this fall "depends."
"It depends on where you are," Roy said, only slightly tongue-in-cheek. "Some areas that had good hatches should see pretty good grouse numbers. We're not at the bottom of the cycle by any means."
The last time that happened was 2009 when the drumming count dropped below 1 grouse per stop as it traditionally does at the bottom of the cycle that generally runs up five years, then down five years. That means — based on history — grouse numbers may drop until about 2021 before heading back up again.
As for this season, "it may not be great, but I think it should be good. We won't know until we start getting some reports in about mid-October,'' Rusch said. "Last year, when a lot of people were complaining, I started getting some pretty good reports in November. It's very local."
Mark Spoden, DNR wildlife manager in Grand Rapids, agreed.
"I haven't seen many broods when I'm out doing field work. But it's hard to see them in summer. We'll know more once we get leaf drop,'' Spoden said.
And as Minnesota biologists note, even the state's down years are better than eastern state peak years.
Did survey miss peak drumming?
Cold weather during the drumming survey may have lead to a lower count, Roy noted. A very cold April may have delayed grouse drumming until after counters had taken their talleys. Surveyors drive back roads and stop to listen at historic spots for males to beat their chests with their wings.
"We try to time it for the peak of drumming activity in each area. But the historic peak is probably earlier than it happened this year. Winter really hung on in April,'' Roy said. That would mean there are more grouse than the 2018 drumming report would imply.
More heavy downpours
Roy said grouse are likely "being impacted'' by the increase in heavy rainfall events that was predicted and has come true as the climate warms. Heavy rains in June can wipe out newly hatched grouse vulnerable to exposure.
Those spring/summer storms varied in intensity over just a few miles.
"And we are definitely having more of those events. If you hunt in area where that happened, you may see far fewer birds. If your area didn't experience one of those heavy rain events, you might think (this year) is a pretty good year,'' Roy said.
Grouse harvests go up and down based on grouse populations. But they also depend on how many hunters are out hunting, and the number of grouse hunters is way down.
While hunter number generally go up as grouse population rise — good news sells more licenses — it's still down from historic highs. More than 142,000 people hunted grouse in 1998, a peak drumming year. But in 2016, the most recent year data is available for, only 82,348 hunters pursued grouse. That's a 42 percent decline, following a trend of declining upland and waterfowl hunter numbers
Help needed in West Nile research
If you have a little Crime Scene Investigator in you, and you're going grouse hunting this autumn in north-central Minnesota, the DNR needs you.
Researchers are asking for volunteers to collect blood samples and the hearts from grouse shot this year as the agency looks for the presence of West Nile Virus in the popular game bird (The blood samples are a simple strip test so no vials of blood are necessary).
The DNR wants between 400 and 500 samples from birds shot within a 60-mile radius of either Bemidji or Grand Rapids in what they are calling a pilot study. If high levels of West Nile show up this year the DNR may expand the survey to more areas in 2019.
West Nile virus is known to kill crows and blue jays in Minnesota, and the stuff can be transmitted to humans, but so far hasn't been found in grouse. Then again, until now, the state really hasn't looked that hard for it in grouse.
There's reason for concern: A Pennsylvania study found a connection between more West Nile virus and lower grouse numbers, especially in areas where grouse habitat wasn't the best. In quality habitat areas — a diverse forest with both young and old aspen and other species — the disease didn't seem to have as much impact.
This autumn wildlife biologists in Minnesota, Wisconsin and Michigan are making a concerted, coordinated effort to see if the bird disease is cutting into the grouse population, especially young grouse.
West Nile virus is carried by infected mosquitoes. Not all people or animals bitten by an infected mosquito will contract West Nile virus. There have been no documented cases of people contracting West Nile virus from consuming properly cooked meat.
Some bird species recover quickly and become tolerant to the virus while others, such as blue jays and crows, suffer high mortality rates.
While the adult grouse population has remained mostly consistent on the 10-year cycle "we don't know if West Nile might be impacting the production of young birds, which make up a large portion of what hunters see in the fall," Roy said.
Hunters who would like to help must collect blood samples and hearts from birds within 30 minutes of the bird being shot. Collection kits are now available for pickup at the Bemidji and Grand Rapids regional DNR headquarters buildings.
Researchers also will collect samples at the Ruffed Grouse Society National Hunt in October, Pineridge Grouse Camp, Bowen Lodge, Hoot-N-Holler, from private hunting guides, and from wildlife students at Bemidji State University. The goal is to get at least 400 samples total.
"This is an important citizen science collaboration for us. Working with hunters and students to collect the samples from harvested birds is critical to the success of the project," Roy said.
Return postage and complete instructions are included in the kits.
Go to mndnr.gov/hunting/grouse for more information.