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Species · Iowa · BBS 2026 Release · 1966–2025

Hairy Woodpecker Population Trend in Iowa

All statesForest birds

Hairy Woodpecker in Iowa has risen sharply: up 50% on the route-weighted index since 1969.

+50%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 →
38Routes 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 Hairy Woodpecker 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 →

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 →

Hairy Woodpecker has risen sharply in Iowa: up 50% on the route-weighted index since 1969.

Hairy Woodpecker Population Forecast in Iowa

If the recent trend holds, Hairy Woodpecker in Iowa is projected to fall about 44% by 2030 — from 0.26 in 2025 to a central estimate of 0.14 (95% range 0.00–0.31). A 5-year backtest shows a typical error of ±33%, with 100% of held-out values landing inside the 95% band.

-44%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 →
0.14Projected 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 →
0.00–0.3195% 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 →
±33%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, Hairy Woodpecker in Iowa is projected to fall about 44% by 2030 — from 0.26 in 2025 to a central estimate of 0.14 (95% range 0.00–0.31). A 5-year backtest shows a typical error of ±33%, with 100% 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 →
20260.140.000.31
20270.140.000.31
20280.140.000.31
20290.140.000.31
20300.140.000.31

Hairy Woodpecker Survey Routes in Iowa

Routes recording Hairy Woodpecker 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 →
Washington320131968
Lafayette320152004
College Spgs219911971
Bryant219991978
Cedar Valley219851975
Panther220251968
Zearing219941988
Sioux City220231968
Festina220211968
Mt Hamill120251967
Exline119771977
Melrose120161983
Bedford120161981
West Liberty120141972
Brooklyn120111998
Williamsburg120041986
Red Rock120241970
Desmoines119781968
Neola120251969
Wales120171973
Maquoketa120241971
Alice119961972
Prairieburg120241979
Hudson120251975
Dinsdale120251981

Hairy Woodpecker Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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