BirdAnalyst
Species · Washington · BBS 2026 Release · 1966–2025

Brewer's Blackbird Population Trend in Washington

All statesGeneralists

Brewer's Blackbird in Washington has declined: down 36% on the route-weighted index since 1970.

-36%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 →
95Routes 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 Brewer's Blackbird 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 Brewer's Blackbird in Washington. See the full index history below.

Brewer's Blackbird Population Forecast in Washington

If the recent trend holds, Brewer's Blackbird in Washington is projected to stay roughly flat through 2030, near 14 (95% range 2.2–25). A 5-year backtest shows a typical error of ±71.8%, with 100% of held-out values landing inside the 95% band.

+4%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 →
14Projected 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 →
2.2–2595% 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 →
±71.8%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, Brewer's Blackbird in Washington is projected to stay roughly flat through 2030, near 14 (95% range 2.2–25). A 5-year backtest shows a typical error of ±71.8%, 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 →
2026153.226
2027153.026
2028142.726
2029142.526
2030142.225

Brewer's Blackbird Survey Routes in Washington

Routes recording Brewer's Blackbird 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 →
Scootney Reservoir23920252009
Mesa15120081994
Columbia Nwr12820221992
Bay View11520171993
Ewan 211320252023
Harwood9519971993
Othello9119911981
Asotin7120251981
Walla Walla7119931993
Wapato6720221971
Potholes6220231996
Waitsburg5020041994
Pomona4919991998
Ewan3320191983
Twisp3220241969
Ellensburg2620251981
Chewelah2420211977
Yakima2420251993
Keystone2220251994
Issaquah1919871969
Snowden1920251971
Nighthawk1920251992
Port Angeles1820251970
Laurier1820221995
Cloverland1620251993

Brewer's Blackbird Population Trend in Other States

arizonacaliforniacoloradoidahoindianamichiganminnesotamontananebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwisconsinwyoming

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