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

Warbling Vireo Population Trend in New Hampshire

All statesForest birds

Warbling Vireo in New Hampshire has edged up: up 19% on the route-weighted index since 1968.

+19%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 →
25Routes 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 Warbling Vireo 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 →

No notable trend signals for Warbling Vireo in New Hampshire. See the full index history below.

Warbling Vireo Population Forecast in New Hampshire

If the recent trend holds, Warbling Vireo in New Hampshire is projected to rise about 31% by 2029 — from 1.2 in 2024 to a central estimate of 1.6 (95% range 0.91–2.3). A 5-year backtest shows a typical error of ±17.3%, with 100% of held-out values landing inside the 95% band.

+31%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 →
1.6Projected 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 →
0.91–2.395% 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 →
±17.3%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, Warbling Vireo in New Hampshire is projected to rise about 31% by 2029 — from 1.2 in 2024 to a central estimate of 1.6 (95% range 0.91–2.3). A 5-year backtest shows a typical error of ±17.3%, with 100% 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 →
20251.60.902.3
20261.60.912.3
20271.60.912.3
20281.60.912.3
20291.60.912.3

Warbling Vireo Survey Routes in New Hampshire

Routes recording Warbling Vireo 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 →
Marlow520241966
Concord420241966
Strafford420241967
Dixvil Notch420081971
Brentwood319981966
Epsom320211967
Walpole320221970
Dover220241967
Mt Chocorua220241970
Stratford220241966
Clarksville220061993
Jeffers Ntch220021994
Peterborough120241970
Fitzwilliam120241970
Hopkinton120241967
Canterbury120241973
Gilmantn I W120241970
Wilmot120151966
Lempster120241966
Crawford Not119751967
Jefferson Hl120231967
Franconia120231967
Milan120241968
Glen120231976
East Kingston120241999

Warbling Vireo Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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