BirdAnalyst
Species · New Hampshire · BBS 2026 Release · 1966–2025

Pine Warbler Population Trend in New Hampshire

All statesForest birds

Pine Warbler in New Hampshire has surged: up 55× on the route-weighted index since 1968.

55×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 →
23Routes 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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Pine Warbler 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 →

Pine Warbler has surged in New Hampshire: up 55× on the route-weighted index since 1968.

Pine Warbler Population Forecast in New Hampshire

If the recent trend holds, Pine Warbler in New Hampshire is projected to stay roughly flat through 2030, near 8.7 (95% range 6.0–11). A 5-year backtest shows a typical error of ±29.2%, with 60% of held-out values landing inside the 95% band.

-5%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 →
8.7Projected 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 →
6.0–1195% 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 →
±29.2%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, Pine Warbler in New Hampshire is projected to stay roughly flat through 2030, near 8.7 (95% range 6.0–11). A 5-year backtest shows a typical error of ±29.2%, with 60% of held-out values landing inside the 95% band.19662030
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 →
20268.15.411
20278.25.511
20288.45.711
20298.65.811
20308.76.011

Pine Warbler Survey Routes in New Hampshire

Routes recording Pine Warbler 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 →
Fitzwilliam2320251971
Canterbury2320251970
Mt Chocorua2020251967
Lempster1820251997
Walpole1520251970
Glen1520251975
Wilmot1420251977
Dover1220251974
Jefferson Hl1220251969
Brentwood1019981977
Marlow920251981
East Kingston920241999
Concord720251967
Strafford720251966
Gilmantn I W720251970
Franconia720251971
Milan620252001
Stratford620252013
Hopkinton520251967
Peterborough320251966
Epsom320251967
Crawford Not119701966
Jeffers Ntch119931993

Pine Warbler Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianakentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsin

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