Grouse drumming up unexpectedly in northern Minnesota
But the wet, cold spring may reduce chick survival and hunter success.
DULUTH — Grouse drumming was up unexpectedly in northern Minnesota this spring in a year when wildlife biologists expected grouse numbers to be down.
Wildlife experts stop and listen for male grouse drumming each spring along predetermined routes in the forest. This year, they heard 1.9 drums per stop statewide, up from 1.3 drums per stop in 2021, the Minnesota Department of Natural Resources reported Thursday.
The drumming count for Northeastern Minnesota was 2.0 drums per stop, up from 1.4 drums in 2021. In northwestern Minnesota, the count was 2.9 drums per stop, up from 1.4 in 2021.
Grouse numbers generally fluctuate on a roughly 10-year cycle, with the most recent drumming peak being 2017. Biologists had expected a gradual decline in drumming for another year or so.
DNR wildlife experts said the increase likely stems from a warm, dry spring in 2021 that allowed for high grouse chick survival and more grouse in the woods last year. A winter with ample snow on the ground for grouse to roost in also helped survival rates.
But that’s where the good news ends. A cold, wet spring this year, especially the June hatching period, likely means fewer young grouse will be in the woods when the 2022 grouse hunting season starts Sept. 17.
Because nearly two-thirds of the grouse that hunters shoot each fall are young-of-the year, spring nesting success each year likely has as much or more impact on how many grouse hunters see and shoot each fall than does the spring drumming population.
“May and June 2022 (were) much wetter, with widespread flooding and numerous heavy rainfall events throughout much of northern Minnesota, which may adversely affect nest and chick survival in the core of the ruffed grouse range,’’ DNR biologists noted in their annual grouse report. “If this is true, the high spring counts of 2022 may not translate into high fall grouse numbers. In recent years, the drumming survey has not been a reliable predictor of fall hunting experiences.”
Wisconsin's ruffed grouse drumming count was down 5% this year from 2021.
Sharp-tailed grouse population increases
Sharp-tailed grouse also pulled off an unexpected increase this year compared to 2021 across the bird’s range in eastern Minnesota, where wildlife officials remain worried that the bird is on its way out permanently.
The one-year population increase follows the closure of the 2021 hunting season in east-central Minnesota, “but does not signify long-term recovery of the population,’’ the DNR noted. The sharptail hunting season will remain closed in eastern Minnesota again in 2022.
The number of leks — traditional male display areas or dancing grounds — counted in the east-central region remains low overall, and the leks are smaller in the few areas that still hold sharp-tailed grouse.
This spring counters found 9.8 birds per lek, or dancing area, up from 7.3 last year in the eastern area of the state. They found a total of 205 birds at 21 leks in 2022, up 55% from 132 birds in 2021.
Most of the leks were in Aitkin County, although biologists found three active leks near Tower in St. Louis County, where none had been seen last year.
The 21 leks found is still just a fraction of historic numbers and far below the 70 leks counted as recently as 2010.
“The increase in the east-central region should be regarded cautiously, as warm, dry conditions during spring and summer 2021, followed by favorable winter snow roosting conditions, likely resulted in strong nest success, chick survival and overwinter survival,” said Charlotte Roy, the DNR’s lead grouse biologist. “But we know threats remain for the birds in this area, including habitat loss, as well as more random events like strong storms, flooding and disease outbreaks.”
In northwestern Minnesota, where better sharptail habitat exists, counters found 12.5 birds per lek, stable with recent years.