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

Northern Parula Population Trend in New Hampshire

All statesForest birds

Northern Parula in New Hampshire has surged: up 609% on the route-weighted index since 1968.

+609%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 →
24Routes 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 Northern Parula 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 →

Northern Parula has surged in New Hampshire: up 609% on the route-weighted index since 1968.

Northern Parula Population Forecast in New Hampshire

If the recent trend holds, Northern Parula in New Hampshire is projected to fall about 22% by 2029 — from 5.0 in 2024 to a central estimate of 3.9 (95% range 2.7–5.0). A 5-year backtest shows a typical error of ±21.5%, with 80% of held-out values landing inside the 95% band.

-22%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 →
3.9Projected 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 →
2.7–5.095% 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 →
±21.5%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, Northern Parula in New Hampshire is projected to fall about 22% by 2029 — from 5.0 in 2024 to a central estimate of 3.9 (95% range 2.7–5.0). A 5-year backtest shows a typical error of ±21.5%, 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 →
20253.62.54.8
20263.72.54.8
20273.72.64.9
20283.82.75.0
20293.92.75.0

Northern Parula Survey Routes in New Hampshire

Routes recording Northern Parula 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 →
Clarksville3820241966
Dixville Notch 23120242018
Dixvil Notch1520171966
Milan820241967
Stratford720241966
Jefferson Hl520241966
Franconia520241966
Mt Chocorua420241967
Glen320241977
Jeffers Ntch320241993
Lempster220241973
Crawford Not219751966
Peterborough120231977
Fitzwilliam119941969
Dover120062006
Hopkinton120221976
Epsom120001973
Concord120241987
Strafford120241973
Canterbury120211976
Gilmantn I W120211993
Wilmot120241971
Walpole120231977
Marlow120122012

Northern Parula Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsin

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