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

Blue-headed Vireo Population Trend in New Hampshire

All statesForest birds

Blue-headed Vireo in New Hampshire has surged: up 206% on the route-weighted index since 1968.

+206%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 →
26Routes 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 Blue-headed 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 →

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 →

Blue-headed Vireo has surged in New Hampshire: up 206% on the route-weighted index since 1968.

Blue-headed Vireo Population Forecast in New Hampshire

If the recent trend holds, Blue-headed Vireo in New Hampshire is projected to rise about 90% by 2030 — from 2.3 in 2025 to a central estimate of 4.3 (95% range 2.6–6.0). A 5-year backtest shows a typical error of ±30.2%, with 60% of held-out values landing inside the 95% band.

+90%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 →
4.3Projected 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 →
2.6–6.095% 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 →
±30.2%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, Blue-headed Vireo in New Hampshire is projected to rise about 90% by 2030 — from 2.3 in 2025 to a central estimate of 4.3 (95% range 2.6–6.0). A 5-year backtest shows a typical error of ±30.2%, 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 →
20264.12.45.8
20274.22.55.9
20284.22.55.9
20294.32.66.0
20304.32.66.0

Blue-headed Vireo Survey Routes in New Hampshire

Routes recording Blue-headed 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 →
Dixville Notch 21120252018
Stratford620251967
Dixvil Notch620171967
Clarksville620251966
Mt Chocorua520251966
Crawford Not519751968
Franconia420251966
Milan420251966
Gilmantn I W320241971
Walpole320251967
Jefferson Hl320251966
Glen320251975
Strafford220241966
Jeffers Ntch220251993
Peterborough120251969
Brentwood119931973
Fitzwilliam120251966
Dover120071966
Hopkinton120241968
Epsom120231968
Concord120231967
Canterbury120251970
Wilmot120251971
Marlow120251967
Lempster120241966

Blue-headed Vireo Population Trend in Other States

alabamaconnecticutgeorgiakentuckymainemarylandmassachusettsmichiganminnesotanew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandsouth-carolinatennesseevermontvirginiawest-virginiawisconsin

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