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Species · Washington · BBS 2026 Release · 1966–2025

Varied Thrush Population Trend in Washington

All statesForest birds

Varied Thrush in Washington has held roughly steady: down 1% on the route-weighted index since 1970.

-1%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 →
61Routes 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 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 67% by 2030 — from 2.8 in 2025 to a central estimate of 4.6 (95% range 1.3–7.9). A 5-year backtest shows a typical error of ±103.6%, with 100% of held-out values landing inside the 95% band.

+67%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 →
4.6Projected 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 →
1.3–7.995% 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 →
±103.6%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 67% by 2030 — from 2.8 in 2025 to a central estimate of 4.6 (95% range 1.3–7.9). A 5-year backtest shows a typical error of ±103.6%, 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 →
20264.61.37.9
20274.61.37.9
20284.61.37.9
20294.61.37.9
20304.61.37.9

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
White Chuck2720251992
Packwood2420251975
Cascade Riv2120061988
Greenwater2020252015
Cedar Falls1920141992
Glacier1720241975
Neilton1719751975
Mt St Helens1720241992
Mt. Adams1720251993
Index1319971997
Sullivan Lake 21120252000
Rimrock1020251968
Montesand920131986
Northport920071997
Index819711968
Bunker Hill820241968
Snowden819731971
Port Angeles720102001
Suiattle Riv720191993
No Cascades520191988
Index 2520232014
Hurricane Rg520251992
Rainier520102007
Kendall420241981

Varied Thrush Population Trend in Other States

alaskacaliforniaidahomontanaoregon

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