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

Hairy Woodpecker Population Trend in Maine

All statesForest birds

Hairy Woodpecker in Maine has risen sharply: up 62% on the route-weighted index since 1968.

+62%Since 1968TrendPercent 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 →
77Routes 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 Hairy Woodpecker Trends in MaineNotable 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 Maine: up 62% on the route-weighted index since 1968.

Hairy Woodpecker Population Forecast in Maine

If the recent trend holds, Hairy Woodpecker in Maine is projected to stay roughly flat through 2029, near 1.9 (95% range 1.1–2.6). A 5-year backtest shows a typical error of ±16.8%, with 80% of held-out values landing inside the 95% band.

-3%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 →
1.9Projected 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 →
1.1–2.695% 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 →
±16.8%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, Hairy Woodpecker in Maine is projected to stay roughly flat through 2029, near 1.9 (95% range 1.1–2.6). A 5-year backtest shows a typical error of ±16.8%, with 80% of held-out values landing inside the 95% band.19662029
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 →
20251.81.12.6
20261.91.12.6
20271.91.12.6
20281.91.12.6
20291.91.12.6

Hairy Woodpecker Survey Routes in Maine

Routes recording Hairy Woodpecker in Maine.
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 →
Waite1219771977
Brooks920191977
Northfield919811976
Hancock820241970
Charleston720191975
Pillsbury Pd719681968
East Troy620191973
Eastbrook520241973
Reeds420241983
Seboomook Lk420141972
Clayton Lake420011977
Baker Lake420051994
Wilson Mills320241983
Harmony320241968
Castine320051976
Carrying Pl320241995
Wytopitlock319981976
Grnd Lk Strm319991990
Boundary320161993
Yankeetuladi320081994
Andover320192014
Searsport320242002
Newcastle220101971
Manchester219951971
Hermon220191966

Hairy Woodpecker Population Trend in Other States

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

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