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

Pine Warbler Population Trend in New Hampshire

All statesForest birds

Pine Warbler in New Hampshire has surged: up 58× on the route-weighted index since 1968.

58×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 →
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 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 58× 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 2029, near 8.5 (95% range 5.7–11). A 5-year backtest shows a typical error of ±30.3%, with 60% 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 →
8.5Projected 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 →
5.7–1195% 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 →
±30.3%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, Pine Warbler in New Hampshire is projected to stay roughly flat through 2029, near 8.5 (95% range 5.7–11). A 5-year backtest shows a typical error of ±30.3%, with 60% 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 →
20257.85.111
20268.05.311
20278.15.411
20288.35.611
20298.55.711

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 →
Fitzwilliam1720241971
Strafford1720241966
Mt Chocorua1520241967
Canterbury1420241970
Wilmot1420241977
Dover1320241974
Concord1320241967
Lempster1320241997
Hopkinton1220241967
Brentwood1019981977
Marlow920241981
Glen920241975
East Kingston920241999
Gilmantn I W720241970
Walpole720241970
Epsom620231967
Milan620242001
Peterborough520241966
Stratford520242013
Jefferson Hl320241969
Franconia320241971
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 2026-05-22.