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Species · Washington · BBS 2025 Release · 1966–2024

Swainson's Thrush Population Trend in Washington

All statesForest birds

Swainson's Thrush in Washington has declined: down 35% on the route-weighted index since 1970.

-35%Since 1970
82Routes In State
56Years

Notable Swainson's Thrush Trends in Washington

No notable trend signals for Swainson's Thrush in Washington. See the full index history below.

Swainson's Thrush Population Forecast in Washington

If the recent trend holds, Swainson's Thrush in Washington is projected to fall about 21% by 2029 — from 24 in 2024 to a central estimate of 19 (95% range 8.8–29). A 5-year backtest shows a typical error of ±24%, with 100% of held-out values landing inside the 95% band.

-21%Change by 2029
19Projected 2029 index
8.8–2995% range
±24%Backtest error
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 index95% low95% high
2025199.529
2026199.329
2027199.229
2028199.029
2029198.829

Swainson's Thrush Survey Routes in Washington

Routes recording Swainson's Thrush in Washington.
Pe Ell9820231993
Ozette8820241971
Raymond 28420242022
Neilton6519751975
Raymond6520211993
Taholah6420221969
Kendall6420241981
Concrete6420242013
Montesand6120241986
Sullivan Lake 26020242000
Issaquah5819871969
Ilwaco5720241975
Mendota 35420242005
Carnation5020241988
Index4919711968
South Elma4920241975
Vashon Is.4820241995
Mendota4519881977
Index 24120232014
Newhalem4020241968
Port Angeles3920241970
Warm Beach3920171968
Suiattle Riv3820191993
White Chuck3720241992
Twin Lakes3620241983

Swainson's Thrush Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahoillinoismainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinaoregonpennsylvaniasouth-dakotautahvermontvirginiawest-virginiawisconsinwyoming

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