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

Western Bluebird Population Trend in Arizona

All statesForest birds

Western Bluebird in Arizona has held roughly steady: up 9% on the route-weighted index since 1970.

+9%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 →
40Routes 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 Western Bluebird Trends in ArizonaNotable 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 Western Bluebird in Arizona. See the full index history below.

Western Bluebird Population Forecast in Arizona

If the recent trend holds, Western Bluebird in Arizona is projected to rise about 25% by 2029 — from 2.2 in 2024 to a central estimate of 2.8 (95% range 1.1–4.5). A 5-year backtest shows a typical error of ±65.7%, with 80% of held-out values landing inside the 95% band.

+25%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 →
2.8Projected 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 →
1.1–4.595% 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 →
±65.7%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 Arizona is projected to rise about 25% by 2029 — from 2.2 in 2024 to a central estimate of 2.8 (95% range 1.1–4.5). A 5-year backtest shows a typical error of ±65.7%, with 80% 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 →
20252.70.984.4
20262.71.04.5
20272.71.04.5
20282.81.04.5
20292.81.14.5

Western Bluebird Survey Routes in Arizona

Routes recording Western Bluebird in Arizona.
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 →
Happy Jack5320241977
Sawmill3320141988
The Gap2719761976
Tonto Vill.2020211992
Pinetop1820221993
Sprucedale1820231992
Aztec Peak1619781974
Williams1220191993
Forest Lakes1220241992
Tsaile1120231993
Maine820241992
Flagstaff720221988
Mormon Lake719751968
Cow Springs720221992
Blue619911974
Skull Valley620221997
Black Mesa419951988
Patagonia419971997
Alpine420231992
Hunt320171976
Dry Park320241992
Page320191995
Castle Butte320051993
Mt Trumbull219931980
House Rock220221968

Western Bluebird Population Trend in Other States

californiacoloradoidahomontananevadanew-mexicooregontexasutahwashingtonwyoming

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