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

Red-tailed Hawk Population Trend in New Hampshire

All statesGeneralists

Red-tailed Hawk in New Hampshire has surged: up 459% on the route-weighted index since 1971.

+459%Since 1971TrendPercent 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 →
22Routes 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 →
43YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Red-tailed Hawk 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 →

Red-tailed Hawk has surged in New Hampshire: up 459% on the route-weighted index since 1971.

Red-tailed Hawk Population Forecast in New Hampshire

If the recent trend holds, Red-tailed Hawk in New Hampshire is projected to fall about 50% by 2029 — from 0.41 in 2024 to a central estimate of 0.20 (95% range 0.04–0.36). A 5-year backtest shows a typical error of ±44.9%, with 80% of held-out values landing inside the 95% band.

-50%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 →
0.20Projected 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 →
0.04–0.3695% 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 →
±44.9%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, Red-tailed Hawk in New Hampshire is projected to fall about 50% by 2029 — from 0.41 in 2024 to a central estimate of 0.20 (95% range 0.04–0.36). A 5-year backtest shows a typical error of ±44.9%, 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 →
20250.190.040.35
20260.200.040.35
20270.200.040.36
20280.200.040.36
20290.200.040.36

Red-tailed Hawk Survey Routes in New Hampshire

Routes recording Red-tailed Hawk 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 →
East Kingston320242003
Marlow220241980
Peterborough120141971
Brentwood119981981
Fitzwilliam120241979
Dover120241986
Hopkinton120222022
Epsom120221985
Concord120231995
Strafford120242004
Canterbury120161981
Gilmantn I W120122012
Wilmot120102010
Mt Chocorua120002000
Walpole120241974
Lempster119661966
Jefferson Hl120101991
Franconia120231968
Milan120191973
Stratford119811972
Dixvil Notch119941994
Clarksville120002000

Red-tailed Hawk Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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