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Species · Washington · BBS 2025 Release · 1966–2024

Varied Thrush Population Trend in Washington

All statesForest birds

Varied Thrush in Washington has held roughly steady: down 5% on the route-weighted index since 1970.

-5%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 →
60Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Varied Thrush Trends in WashingtonNotable 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 Varied Thrush in Washington. See the full index history below.

Varied Thrush Population Forecast in Washington

If the recent trend holds, Varied Thrush in Washington is projected to rise about 84% by 2029 — from 2.6 in 2024 to a central estimate of 4.8 (95% range 1.5–8.1). A 5-year backtest shows a typical error of ±89.6%, with 100% of held-out values landing inside the 95% band.

+84%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 →
4.8Projected 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 →
1.5–8.195% 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 →
±89.6%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, Varied Thrush in Washington is projected to rise about 84% by 2029 — from 2.6 in 2024 to a central estimate of 4.8 (95% range 1.5–8.1). A 5-year backtest shows a typical error of ±89.6%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20254.81.58.0
20264.81.58.1
20274.81.58.1
20284.81.58.1
20294.81.58.1

Varied Thrush Survey Routes in Washington

Routes recording Varied Thrush in Washington.
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 →
Mt Rainier3420211990
Mt. Adams2220241993
Cascade Riv2120061988
Cedar Falls1920141992
Glacier1720241975
Neilton1719751975
Mt St Helens1720241992
White Chuck1620241992
Sullivan Lake 21420242000
Index1319971997
Greenwater1320242015
Packwood1120241975
Montesand920131986
Northport920071997
Newhalem820241968
Index819711968
Bunker Hill820241968
Snowden819731971
Port Angeles720102001
Suiattle Riv720191993
Ozette520241971
No Cascades520191988
Index 2520232014
Rainier520102007
Rimrock420241968

Varied Thrush Population Trend in Other States

alaskacaliforniaidahomontanaoregon

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