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

Wood Thrush Population Trend in Pennsylvania

All statesForest birds

Wood Thrush in Pennsylvania has edged down: down 25% on the route-weighted index since 1968.

-25%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 →
136Routes 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 Wood Thrush Trends in PennsylvaniaNotable 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 Wood Thrush in Pennsylvania. See the full index history below.

Wood Thrush Population Forecast in Pennsylvania

If the recent trend holds, Wood Thrush in Pennsylvania is projected to stay roughly flat through 2029, near 8.6 (95% range 5.1–12). A 5-year backtest shows a typical error of ±8.8%, with 100% of held-out values landing inside the 95% band.

+1%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 →
8.6Projected 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 →
5.1–1295% 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 →
±8.8%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, Wood Thrush in Pennsylvania is projected to stay roughly flat through 2029, near 8.6 (95% range 5.1–12). A 5-year backtest shows a typical error of ±8.8%, 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 →
20259.05.612
20268.95.512
20278.85.312
20288.75.212
20298.65.112

Wood Thrush Survey Routes in Pennsylvania

Routes recording Wood Thrush in Pennsylvania.
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 →
Stoneybreak3320241992
Pine Gr Mill2920241967
Mill Run2620241978
Tussey Mtn.2520241993
Rector2419771966
Drehersville 22220242000
Duvall2120211974
Big Flat2119811966
Carsonville2020231966
Laurel Hill2020241978
Roulette1920211970
Clear Spring1920241966
Needmore1919911966
Ellenton1920241982
Jefferson1820241966
Landisburg1720241978
South Mtn1720231986
Broad Mtn.1720241993
Marsh Hill1620241983
Akeley1519791966
N Washington1520241967
Doubling Gap1519771966
Roulette 21520242022
Mawr Glen1420241966
Duboistown1420241987

Wood Thrush Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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