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

Blue Jay Population Trend in New Hampshire

All statesForest birds

Blue Jay in New Hampshire has fallen sharply: down 53% on the route-weighted index since 1968.

-53%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 Jay 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 declinecomputed 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 Jay has fallen sharply in New Hampshire: down 53% on the route-weighted index since 1968.

Blue Jay Population Forecast in New Hampshire

If the recent trend holds, Blue Jay in New Hampshire is projected to stay roughly flat through 2030, near 7.9 (95% range 3.1–13). A 5-year backtest shows a typical error of ±12.3%, with 100% of held-out values landing inside the 95% band.

+1%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 →
7.9Projected 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 →
3.1–1395% 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 →
±12.3%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, Blue Jay in New Hampshire is projected to stay roughly flat through 2030, near 7.9 (95% range 3.1–13). A 5-year backtest shows a typical error of ±12.3%, 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 →
20268.73.914
20278.53.713
20288.33.513
20298.13.313
20307.93.113

Blue Jay Survey Routes in New Hampshire

Routes recording Blue Jay 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 →
Wilmot1520251966
Milan1420251966
Canterbury1320251966
Dixville Notch 21320252018
Concord1220251966
Glen1220251975
Brentwood1119981966
Dover1120251966
Lempster1020251966
East Kingston1020251999
Franconia920251966
Mt Chocorua820251966
Fitzwilliam720251966
Hopkinton720251966
Marlow720251966
Dixvil Notch720171966
Clarksville720251966
Gilmantn I W620251969
Jefferson Hl620251966
Peterborough420251966
Epsom420251966
Walpole320251966
Strafford220251966
Crawford Not219751966
Stratford120241966

Blue Jay Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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