The Minnesota DNR coordinates ruffed grouse (Bonasa umbellus) drumming surveys each
spring with the help of wildlife staff and cooperating federal, tribal, and county biologists. Mean
ruffed grouse drums per stop (dps) were 1.7 statewide (95% confidence interval = 1.5 – 2.0) which is down from last year and consistent with the peak in the population cycle occurring in
2024. This declining pattern was observed in the Northeast, Central Hardwoods, and Southeast survey regions, which comprise the majority of survey routes (124 of 129 routes surveyed this
year). However, in the Northwest, dps increased over the last 2 years. Survey effort has been down in this region the last 2 years due to federal staffing reductions; 5 of 8 routes weresurveyed which may not be representative of the region. The ruffed grouse drumming survey
assumes that only the number of grouse varies among years. The drumming survey is useful for monitoring long-term population trends, but interpretation of a few years of data or less can be tenuous.
Statewide ruffed grouse drums were down from last year and averaged 1.7 dps (95% confidence interval = 1.5 – 2.0 dps; Figure 2). Drum counts were 1.9 (1.6 – 2.2) dps in the Northeast (n = 103 routes), 2.4 (1.2 – 3.5) dps in the Northwest (n = 5), 1.0 (0.5 – 1.5) dps in the
Central Hardwoods (n = 13), and 0.3 (0.1 – 0.6) dps in the Southeast region (n = 8; Figure 3a-d). Thus, in the Northeast, Central Hardwoods, and Southeast regions dps are clearly in the
declining phase of the cycle, whereas in the Northwest, dps have increased the last 2 years.
Survey effort has been down in the Northwest the last 2 seasons due to changes in federal staffing, so only 5 of 8 routes were completed this year. This small sample may not be representative of the region so should be interpreted with caution.
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