BirdAnalyst
Species · Vermont · BBS 2026 Release · 1966–2025

Evening Grosbeak Population Trend in Vermont

All statesForest birds

Evening Grosbeak in Vermont has fallen sharply: down 71% on the route-weighted index since 1968.

-71%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 →
21Routes 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 →
41YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Evening Grosbeak 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 →

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 →

Evening Grosbeak has fallen sharply in Vermont: down 71% on the route-weighted index since 1968.

Evening Grosbeak Population Forecast in Vermont

If the recent trend holds, Evening Grosbeak in Vermont is projected to rise about 752% by 2030 — from 0.06 in 2025 to a central estimate of 0.48 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±1184.2%, with 60% of held-out values landing inside the 95% band.

+752%Change by 2030TrendPercent 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 →
0.48Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.395% 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 →
±1184.2%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, Evening Grosbeak in Vermont is projected to rise about 752% by 2030 — from 0.06 in 2025 to a central estimate of 0.48 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±1184.2%, with 60% of held-out values landing inside the 95% band.19662030
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 →
20260.480.001.3
20270.480.001.3
20280.480.001.3
20290.480.001.3
20300.480.001.3

Evening Grosbeak Survey Routes in Vermont

Routes recording Evening Grosbeak 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 →
Stratton519991967
Gaysville420091967
Shaftsbury320061992
Marlboro219891989
Post Mills220081993
W Rutland219961996
East Haven219991966
Middlesex220081968
Newbury220041988
Hardwick220061974
Newbury 2220212005
Landgrove120171967
S Reading120091989
St Johnsbury120061971
Northfld Fls120041992
East Calais120191974
Greensboro120251974
Waterville119751967
Hinesburg119931993
Colchester119861986
Stowe120221993

Evening Grosbeak Population Trend in Other States

arizonacaliforniacoloradoconnecticutidahomainemassachusettsmichiganminnesotamontananevadanew-hampshirenew-mexiconew-yorkoregonsouth-dakotautahwashingtonwisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.