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

Broad-winged Hawk Population Trend in New Hampshire

All statesGeneralists

Broad-winged Hawk in New Hampshire has surged: up 106% on the route-weighted index since 1968.

+106%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 →
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 Broad-winged 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 →

Broad-winged Hawk has surged in New Hampshire: up 106% on the route-weighted index since 1968.

Broad-winged Hawk Population Forecast in New Hampshire

If the recent trend holds, Broad-winged Hawk in New Hampshire is projected to rise about 70% by 2029 — from 0.36 in 2024 to a central estimate of 0.62 (95% range 0.25–0.98). A 5-year backtest shows a typical error of ±38.6%, with 80% of held-out values landing inside the 95% band.

+70%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 →
0.62Projected 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 →
0.25–0.9895% 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 →
±38.6%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, Broad-winged Hawk in New Hampshire is projected to rise about 70% by 2029 — from 0.36 in 2024 to a central estimate of 0.62 (95% range 0.25–0.98). A 5-year backtest shows a typical error of ±38.6%, 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 →
20250.590.230.95
20260.600.230.96
20270.600.240.97
20280.610.250.97
20290.620.250.98

Broad-winged Hawk Survey Routes in New Hampshire

Routes recording Broad-winged 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 →
Mt Chocorua320231975
Walpole320241966
Dixville Notch 2320232018
Fitzwilliam220221968
Hopkinton220181970
Epsom220231985
Strafford220221966
Gilmantn I W220221977
Wilmot220241974
Jefferson Hl220231967
Peterborough120181971
Brentwood119921967
Dover120241975
Concord120231966
Canterbury120211966
Marlow120211967
Lempster120231972
Crawford Not119741974
Franconia120221971
Milan120231966
Stratford119991972
Dixvil Notch120151968
Clarksville120211970
Glen120241975
East Kingston120242006

Broad-winged Hawk Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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