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

Western Bluebird Population Trend in Oregon

All statesForest birds

Western Bluebird in Oregon has risen sharply: up 74% on the route-weighted index since 1971.

+74%Since 1971TrendPercent 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 →
85Routes 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 →
55YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Western Bluebird Trends in OregonNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Western Bluebird has risen sharply in Oregon: up 74% on the route-weighted index since 1971.

Western Bluebird Population Forecast in Oregon

If the recent trend holds, Western Bluebird in Oregon is projected to rise about 17% by 2029 — from 0.53 in 2024 to a central estimate of 0.62 (95% range 0.31–0.93). A 5-year backtest shows a typical error of ±7.3%, 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 →
0.62Projected 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 →
0.31–0.9395% 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 →
±7.3%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, Western Bluebird in Oregon is projected to rise about 17% by 2029 — from 0.53 in 2024 to a central estimate of 0.62 (95% range 0.31–0.93). A 5-year backtest shows a typical error of ±7.3%, 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 →
20250.590.290.90
20260.600.290.91
20270.610.300.91
20280.610.300.92
20290.620.310.93

Western Bluebird Survey Routes in Oregon

Routes recording Western Bluebird in Oregon.
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 →
Eightmile919911991
Emigrant Lk820011973
Sams Valley820241994
Albee620231976
Elkton620241999
Barnhouse520242012
Salem520231994
Umpqua420241968
Days Creek420211972
Garfield420222008
Silver Creek420171991
Silvies420231995
Zumwalt420051995
Harlan 2420162016
Mount Vernon320241988
Davis Lake320132013
Modoc Point 2320242024
Trask Summit319921992
Howard Mdws.320191992
Waldport319991999
Green320241994
Ruch320231992
Black Mtn.320041996
Riley Peak320142010
Shellrock220092006

Western Bluebird Population Trend in Other States

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