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

Winter Wren Population Trend in Vermont

All statesForest birds

Winter Wren in Vermont has surged: up 355% on the route-weighted index since 1968.

+355%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 →
26Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Winter Wren 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 increasecomputed 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 →

Winter Wren has surged in Vermont: up 355% on the route-weighted index since 1968.

Winter Wren Population Forecast in Vermont

If the recent trend holds, Winter Wren in Vermont is projected to rise about 33% by 2029 — from 2.7 in 2024 to a central estimate of 3.6 (95% range 1.2–6.0). A 5-year backtest shows a typical error of ±44.5%, with 100% of held-out values landing inside the 95% band.

+33%Change by 2029TrendPercent 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 →
3.6Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
1.2–6.095% 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 →
±44.5%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, Winter Wren in Vermont is projected to rise about 33% by 2029 — from 2.7 in 2024 to a central estimate of 3.6 (95% range 1.2–6.0). A 5-year backtest shows a typical error of ±44.5%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20253.51.15.9
20263.51.15.9
20273.51.16.0
20283.61.26.0
20293.61.26.0

Winter Wren Survey Routes in Vermont

Routes recording Winter Wren 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 →
Stratton720241966
Waterville719801979
Marlboro620241966
Landgrove620241972
Middlesex620241969
East Calais520241966
Stowe520241988
Gaysville420191966
East Haven420241966
Hardwick420241971
Newbury320041986
Greensboro320241967
Shaftsbury220011969
St Johnsbury220241970
Northfld Fls220211980
Fletcher220231974
Colchester220031987
Newbury 2220232005
North Pownal120111974
S Reading120231968
Post Mills120241966
S Wallingfrd120221980
W Rutland120061970
Hinesburg119921981
Grand Isle120001987

Winter Wren Population Trend in Other States

connecticutmainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinaohiopennsylvaniatennesseevirginiawest-virginiawisconsin

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