BirdAnalyst
Species · Washington · BBS 2025 Release · 1966–2024

Yellow Warbler Population Trend in Washington

All statesForest birds

Yellow Warbler in Washington has declined: down 48% on the route-weighted index since 1970.

-48%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 →
97Routes 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 Yellow Warbler 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 Yellow Warbler in Washington. See the full index history below.

Yellow Warbler Population Forecast in Washington

If the recent trend holds, Yellow Warbler in Washington is projected to fall about 17% by 2029 — from 5.4 in 2024 to a central estimate of 4.4 (95% range 1.4–7.5). A 5-year backtest shows a typical error of ±9.9%, with 100% of held-out values landing inside the 95% band.

-17%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 →
4.4Projected 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 →
1.4–7.595% 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 →
±9.9%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, Yellow Warbler in Washington is projected to fall about 17% by 2029 — from 5.4 in 2024 to a central estimate of 4.4 (95% range 1.4–7.5). A 5-year backtest shows a typical error of ±9.9%, 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 →
20254.51.57.5
20264.51.57.5
20274.51.57.5
20284.51.57.5
20294.41.47.5

Yellow Warbler Survey Routes in Washington

Routes recording Yellow Warbler 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 →
Waitsburg3620041994
Mcchord3020151996
Twisp2320241969
Chewelah2320211977
Lake Chelan2120241988
Nighthawk2020241992
Spring Lake1920241982
Ardenvoir1719871970
Leavenworth1720241981
Laurier1720221996
Index1619711968
Omak Creek1620241996
Keller1520071968
L. Wenatchee1420241993
Mazama1320221993
Newhalem1120241968
Blewett Pass1120241995
Northport1120241996
Cloverland1120241993
Reardan1020241968
Ellensburg1020241981
Pomeroy1020241993
Cougar920231968
Twin Lakes920241983
Bay View920171993

Yellow Warbler Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

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