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

Hairy Woodpecker Population Trend in Arizona

All statesForest birds

Hairy Woodpecker in Arizona has surged: up 83% on the route-weighted index since 1970.

+83%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 →
27Routes 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 →
53YearsYears 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 ArizonaNotable 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 surged in Arizona: up 83% on the route-weighted index since 1970.

Hairy Woodpecker Population Forecast in Arizona

If the recent trend holds, Hairy Woodpecker in Arizona is projected to rise about 134% by 2029 — from 0.40 in 2024 to a central estimate of 0.94 (95% range 0.35–1.5). A 5-year backtest shows a typical error of ±61.6%, with 80% of held-out values landing inside the 95% band.

+134%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 →
0.94Projected 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 →
0.35–1.595% 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 →
±61.6%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 Arizona is projected to rise about 134% by 2029 — from 0.40 in 2024 to a central estimate of 0.94 (95% range 0.35–1.5). A 5-year backtest shows a typical error of ±61.6%, 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 →
20250.910.331.5
20260.920.331.5
20270.920.341.5
20280.930.351.5
20290.940.351.5

Hairy Woodpecker Survey Routes in Arizona

Routes recording Hairy Woodpecker 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 →
Pinetop920222003
Mormon Lake719741968
Prescott620221976
Mt. Graham620231996
Forest Lakes520241992
Alpine420231993
Happy Jack420241977
Flagstaff320221988
Dry Park320241992
Williams320191993
House Rock219781978
Portal220241977
Sawmill220141989
Aztec Peak219781974
Blue219911974
Tsaile220231995
Sprucedale220231992
Black Mesa119941988
Round Rock119891970
Zeniff119701970
Toroweap120171999
Cow Springs120172017
Maine120221992
Castle Butte119921992
Tonto Vill.120211994

Hairy Woodpecker Population Trend in Other States

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

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