July 19, 2019 at 5:05 p.m.
Impetus behind grouse population declines still unsure
By Beckie Gaskill-bjoki@lakelandtimes.com
Last month, Mark Witecha, upland wildlife ecologist with the Department of Natural Resources (DNR) presented information on the 2019 drumming survey as well as 2018 hunter survey responses. There were more sportsmen and women looking to hunt grouse in 2018, than 2017, with 69,090 hunters in the latter year and 64,533 in the previous year, pointing to the continuing popularity of the pursuit. Total days spent afield, however, were down slightly, at 552,293 versus 583,917 in 2017. Harvest, too, declined by about the same 5 percent as days afield with this year's reported harvest coming in at 173,347, approximately a 12,000-bird decline from last year's 185,336 grouse harvest.
Witecha also presented the board with drumming survey results from this year, which pointed to a population rebound over 2018. Overall, drumming survey results statewide showed a 41 percent increase over 2018 numbers. This was especially positive in the north, where habitat is most suitable for grouse populations. In the Central Zone, drumming surveys were up 35 percent, with 11 survey routes seeing increases and only four seeing decreases. In the Northern Zone, drumming surveys showed a 48 percent increase in populations with 24 routes seeing increases and only five seeing decreases.
Drumming surveys did show population decreases in the southern zones, however Witecha said due to the smaller populations in those zones, the loss of a relatively few birds in number could present themselves on paper as an artificially larger percentage.
In all, it seemed population in the state were pointing once again toward the upward end of the 8-11 year population cycle, which should peak in the next 1-2 years. He said while the cycle is not always perfect or predictable, it has been documented since the 1960s, and looks to be on track again after the decline of last year.
"Much of the gains made in 2019 helps make up for the unexpected loss that we observed in 2018," Witecha said. However, the data do not help to explain that unexpected decline. It did show, he said, the increase in population was on track again with the upward portion of the cycle of the grouse populations.
Witecha also informed the board the Ruffed Grouse Management Plan was on track to be presented to the board at their January meeting. Its first draft was currently under committee review and would be going out for public meeting and review, with a series of meetings being held around the state before the management plan would come to the board at the January meeting.
There was some discussion regarding the possible effects of West Nile Virus and what the committee thought or hypothesized in that regard. Formal result were not yet available, but last year, Witecha said, 16 dead grouse were turned in to the Department outside of the disease prevalence study and three of those tested positive for West Nile. Of the 500 kits sent out ot hunters, 240 samples were sent back to the Department, he said, which is similar in return rate to Minnesota and Michigan, which are also involved in the same types of studies.
Board member Gary Zimmer, who sits on the Ruffed Grouse Committee, spoke about a study in Pennsylvania which may have some bearing on Wisconsin grouse populations as well. While we have differences from Pennsylvania, he said, perhaps some of the findings there would hold true in our state as well.
In that study, he reported, West Nile had the largest affect on populations in poorer quality habitats. Many of those populations, it said, would not recover. Zimmer went on to say, if this would hold true in Wisconsin, it could be the "last straw" for some populations in the southern part of the state.
Witecha agreed it was something the committee was eager to learn more about. Test results from last year's sample should be back to the department, he said, in late July or early August from the veterinary lab where not only Wisconsin, but also Minnesota, Michigan and Pennsylvania, which are involved in similar studies, have sent the samples from their states.
Last year an emergency rule was put into place to end the ruffed grouse season on the Sunday nearest Jan. 5, rather than extend that season through January in Zone A. The board formally requested the department to bring forth an emergency rule back to them at the August meeting, making that true for this year's hunt as well. The rule will be brought to the board in August for their approval.
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