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

Prairie Warbler Population Trend in Vermont

All statesForest birds

Prairie Warbler in Vermont has held roughly steady: down 7% on the route-weighted index since 1976.

-7%Since 1976TrendPercent 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 →
9Routes 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 →
23YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Prairie Warbler 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 Prairie Warbler in Vermont. See the full index history below.

Prairie Warbler Population Forecast in Vermont

If the recent trend holds, Prairie Warbler in Vermont is projected to rise about 70% by 2028 — from 0.06 in 2023 to a central estimate of 0.10 (95% range 0.01–0.18). A 5-year backtest shows a typical error of ±49.9%, with 80% of held-out values landing inside the 95% band.

+70%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 →
0.10Projected 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 →
0.01–0.1895% 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 →
±49.9%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, Prairie Warbler in Vermont is projected to rise about 70% by 2028 — from 0.06 in 2023 to a central estimate of 0.10 (95% range 0.01–0.18). A 5-year backtest shows a typical error of ±49.9%, with 80% of held-out values landing inside the 95% band.19712028
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 →
20240.090.000.18
20250.090.000.18
20260.090.000.18
20270.090.000.18
20280.100.010.18

Prairie Warbler Survey Routes in Vermont

Routes recording Prairie Warbler 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 →
Marlboro219881988
North Pownal120172017
Stratton120212014
S Reading119721972
Shaftsbury119991976
S Wallingfrd120031999
W Rutland120232023
St Johnsbury119901971
Hinesburg119801980

Prairie Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawarefloridageorgiaillinoisindianakentuckylouisianamainemarylandmassachusettsmichiganmississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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