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

Eastern Bluebird Population Trend in Iowa

All statesForest birds

Eastern Bluebird in Iowa has increased: up 34% on the route-weighted index since 1969.

+34%Since 1969TrendPercent 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 →
39Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Eastern Bluebird Trends in IowaNotable 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 Eastern Bluebird in Iowa. See the full index history below.

Eastern Bluebird Population Forecast in Iowa

If the recent trend holds, Eastern Bluebird in Iowa is projected to rise about 80% by 2030 — from 1.3 in 2025 to a central estimate of 2.3 (95% range 0.71–3.9). A 5-year backtest shows a typical error of ±173.8%, with 60% of held-out values landing inside the 95% band.

+80%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 →
2.3Projected 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 →
0.71–3.995% 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 →
±173.8%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, Eastern Bluebird in Iowa is projected to rise about 80% by 2030 — from 1.3 in 2025 to a central estimate of 2.3 (95% range 0.71–3.9). A 5-year backtest shows a typical error of ±173.8%, with 60% of held-out values landing inside the 95% band.19672030
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 →
20262.20.613.8
20272.20.643.8
20282.30.663.9
20292.30.693.9
20302.30.713.9

Eastern Bluebird Survey Routes in Iowa

Routes recording Eastern Bluebird in Iowa.
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 →
Exline920251974
Washta920141973
Mt Hamill820251967
Alice719991967
College Spgs 2620252005
Red Rock520251968
Lafayette520242003
College Spgs420041967
Williamsburg320101968
Hudson320251971
Bryant220251968
Maquoketa220251967
Zearing219941981
Clare220191984
Titonka220151976
Mccallsburg220241997
Melrose120251980
Bedford120161968
West Liberty120241968
Cedar Valley119971968
Brooklyn120181976
Desmoines119721970
Panther120231984
Washington120251967
Neola120161971

Eastern Bluebird Population Trend in Other States

alabamaarizonaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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