BirdAnalyst
Species · Vermont · BBS 2026 Release · 1966–2025

Broad-winged Hawk Population Trend in Vermont

All statesBirds of prey

Broad-winged Hawk in Vermont has surged: up 198% on the route-weighted index since 1968.

+198%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 →
55YearsYears 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 VermontNotable 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 Vermont: up 198% on the route-weighted index since 1968.

Broad-winged Hawk Population Forecast in Vermont

If the recent trend holds, Broad-winged Hawk in Vermont is projected to fall about 42% by 2030 — from 0.61 in 2025 to a central estimate of 0.36 (95% range 0.11–0.60). A 5-year backtest shows a typical error of ±51%, with 60% of held-out values landing inside the 95% band.

-42%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 →
0.36Projected 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 →
0.11–0.6095% 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 →
±51%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 Vermont is projected to fall about 42% by 2030 — from 0.61 in 2025 to a central estimate of 0.36 (95% range 0.11–0.60). A 5-year backtest shows a typical error of ±51%, 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 →
20260.340.090.59
20270.340.100.59
20280.350.100.59
20290.350.110.60
20300.360.110.60

Broad-winged Hawk Survey Routes in Vermont

Routes recording Broad-winged Hawk in Vermont.
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 →
Greensboro320251967
S Reading220241971
Shaftsbury220251975
Middlesex220241968
Stowe220221991
Marlboro120161995
North Pownal120222022
Stratton120251978
Landgrove120251974
Gaysville120181978
Post Mills120151980
S Wallingfrd120221981
W Rutland120221979
St Johnsbury120211973
East Haven120241975
Northfld Fls120251986
East Calais120251966
Newbury120041998
Hardwick120241966
Fletcher120251993
Waterville119671967
Hinesburg119931993
Colchester120251995
Grand Isle119871987
Newbury 2120222005

Broad-winged Hawk Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvirginiawest-virginiawisconsinwyoming

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