BirdAnalyst
Species · Vermont · BBS 2025 Release · 1966–2024

Ruffed Grouse Population Trend in Vermont

All statesGeneralists

Ruffed Grouse in Vermont has edged down: down 19% on the route-weighted index since 1968.

-19%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 →
24Routes 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 →
54YearsYears 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 VermontNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Ruffed Grouse in Vermont. See the full index history below.

Ruffed Grouse Population Forecast in Vermont

If the recent trend holds, Ruffed Grouse in Vermont is projected to fall about 83% by 2028 — from 0.17 in 2023 to a central estimate of 0.03 (95% range 0.00–0.34). A 5-year backtest shows a typical error of ±80.7%, with 100% of held-out values landing inside the 95% band.

-83%Change by 2028TrendPercent 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 →
0.03Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.3495% 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 →
±80.7%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 Vermont is projected to fall about 83% by 2028 — from 0.17 in 2023 to a central estimate of 0.03 (95% range 0.00–0.34). A 5-year backtest shows a typical error of ±80.7%, with 100% of held-out values landing inside the 95% band.19662028
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 →
20240.050.000.36
20250.040.000.35
20260.040.000.35
20270.030.000.34
20280.030.000.34

Ruffed Grouse Survey Routes in Vermont

Routes recording Ruffed Grouse in Vermont.
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 →
W Rutland420181972
Newbury 2320232012
Hardwick220051967
Marlboro119891966
North Pownal119801973
Stratton120221968
Landgrove119991972
S Reading119801977
Gaysville120181966
Post Mills119861985
Shaftsbury119891978
S Wallingfrd119881969
St Johnsbury120221972
East Haven119851967
Northfld Fls120171980
Middlesex120171975
East Calais120101966
Newbury119931993
Greensboro120221970
Fletcher120151971
Waterville119741970
Hinesburg119741974
Colchester119991999
Stowe119971991

Ruffed Grouse Population Trend in Other States

alaskaarkansascaliforniaconnecticutgeorgiaidahoindianaiowakentuckymainemarylandmassachusettsmichiganminnesotamontananevadanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotatennesseeutahvirginiawashingtonwest-virginiawisconsinwyoming

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