BirdAnalyst
Species · New Hampshire · BBS 2025 Release · 1966–2024

Hairy Woodpecker Population Trend in New Hampshire

All statesForest birds

Hairy Woodpecker in New Hampshire has surged: up 134% on the route-weighted index since 1968.

+134%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 →
26Routes 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 New HampshireNotable 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 New Hampshire: up 134% on the route-weighted index since 1968.

Hairy Woodpecker Population Forecast in New Hampshire

If the recent trend holds, Hairy Woodpecker in New Hampshire is projected to stay roughly flat through 2029, near 2.7 (95% range 2.0–3.3). A 5-year backtest shows a typical error of ±14.3%, with 80% of held-out values landing inside the 95% band.

+2%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 →
2.7Projected 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 →
2.0–3.395% 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 →
±14.3%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 New Hampshire is projected to stay roughly flat through 2029, near 2.7 (95% range 2.0–3.3). A 5-year backtest shows a typical error of ±14.3%, 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 →
20252.62.03.2
20262.62.03.2
20272.62.03.3
20282.72.03.3
20292.72.03.3

Hairy Woodpecker Survey Routes in New Hampshire

Routes recording Hairy Woodpecker in New Hampshire.
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 →
Concord620241967
Walpole620241968
Canterbury520241966
Dixvil Notch520161966
Fitzwilliam420241968
Dover420221966
Strafford420241966
Marlow420241966
Franconia420241966
Clarksville420241971
East Kingston420242002
Jeffers Ntch420191995
Gilmantn I W320241969
Mt Chocorua320241969
Glen320241975
Dixville Notch 2320242018
Peterborough220241967
Hopkinton220221966
Jefferson Hl220231966
Stratford220221966
Brentwood119941966
Epsom120231966
Wilmot120241969
Lempster120241967
Crawford Not119751968

Hairy Woodpecker Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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