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Species · Massachusetts · BBS 2025 Release · 1966–2024

Ruffed Grouse Population Trend in Massachusetts

All statesGeneralists

Ruffed Grouse in Massachusetts has fallen sharply: down 56% on the route-weighted index since 1968.

-56%Since 1968TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
17Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
35YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Ruffed Grouse Trends in MassachusettsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Ruffed Grouse has fallen sharply in Massachusetts: down 56% on the route-weighted index since 1968.

Ruffed Grouse Population Forecast in Massachusetts

If the recent trend holds, Ruffed Grouse in Massachusetts is projected to fall about 11% by 2023 — from 0.05 in 2018 to a central estimate of 0.05 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±16.3%, with 100% of held-out values landing inside the 95% band.

-11%Change by 2023TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.05Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2195% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±16.3%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Ruffed Grouse in Massachusetts is projected to fall about 11% by 2023 — from 0.05 in 2018 to a central estimate of 0.05 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±16.3%, with 100% of held-out values landing inside the 95% band.19662023
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20190.060.000.21
20200.050.000.21
20210.050.000.21
20220.050.000.21
20230.050.000.21

Ruffed Grouse Survey Routes in Massachusetts

Routes recording Ruffed Grouse in Massachusetts.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Hancock220012001
E Dennis119721972
Ware River120101994
Prattville120002000
Newburyport119671967
N Oxford119681968
E Pepperell119731966
Belchertown119951973
Warren119971970
Holden119831983
N Orange120141975
Cummington120121970
Chesterfield120181969
Cheshire119931969
Pittsfield119971970
Sheffield119881974
Cummington 2120172017

Ruffed Grouse Population Trend in Other States

alaskaarkansascaliforniaconnecticutgeorgiaidahoindianaiowakentuckymainemarylandmichiganminnesotamontananevadanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.