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Species · Oregon · BBS 2026 Release · 1966–2025

Swainson's Thrush Population Trend in Oregon

All statesForest birds

Swainson's Thrush in Oregon has edged down: down 21% on the route-weighted index since 1970.

-21%Since 1970TrendPercent 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 →
89Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Swainson's Thrush Trends in OregonNotable 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 Swainson's Thrush in Oregon. See the full index history below.

Swainson's Thrush Population Forecast in Oregon

If the recent trend holds, Swainson's Thrush in Oregon is projected to stay roughly flat through 2030, near 15 (95% range 8.9–20). A 5-year backtest shows a typical error of ±20%, with 100% of held-out values landing inside the 95% band.

+7%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 →
15Projected 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 →
8.9–2095% 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 →
±20%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, Swainson's Thrush in Oregon is projected to stay roughly flat through 2030, near 15 (95% range 8.9–20). A 5-year backtest shows a typical error of ±20%, with 100% of held-out values landing inside the 95% band.19682030
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 →
2026148.620
2027148.720
2028148.720
2029148.820
2030158.920

Swainson's Thrush Survey Routes in Oregon

Routes recording Swainson's Thrush in Oregon.
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 →
Fisher27020101997
Klickitat Mt13919961993
Santiam12420251994
Trask Summit10420241992
Fisher 29120252017
Coquille8820251994
Harlan8720092006
Riley Peak8220161994
Lobster Creek8120252025
Lorane8020251993
Molalla8020251994
Harlan 28020252011
Salado6820251968
Blue River6620251992
Glasgow6420251986
Nicolai Mtn.6420251993
Wedderburn5720251970
Hauser5219851970
Bull Run5120252007
Elkton4820251972
Eagle Creek4720251993
Cool Camp4420131968
Timber3820171968
Winberry3820231968
Waldport3620011992

Swainson's Thrush Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahoillinoismainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinapennsylvaniasouth-dakotautahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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