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

Warbling Vireo Population Trend in New Hampshire

All statesForest birds

Warbling Vireo in New Hampshire has edged up: up 22% on the route-weighted index since 1968.

+22%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 →
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 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 stay roughly flat through 2030, near 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.

+0%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 →
1.6Projected 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 →
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 stay roughly flat through 2030, near 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.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 →
20261.60.912.3
20271.60.912.3
20281.60.912.3
20291.60.912.3
20301.60.912.3

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 →
Fitzwilliam1320251970
Concord520251966
Marlow520241966
Dixvil Notch420081971
Brentwood319981966
Epsom320211967
East Kingston320251999
Peterborough220251970
Strafford220251967
Mt Chocorua220251970
Lempster220251966
Milan220251968
Stratford220241966
Jeffers Ntch220021994
Dover120251967
Hopkinton120251967
Canterbury120241973
Gilmantn I W120251970
Wilmot120151966
Walpole120251970
Crawford Not119751967
Jefferson Hl120251967
Franconia120231967
Clarksville120251993
Glen120231976

Warbling Vireo Population Trend in Other States

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

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