BirdAnalyst
Species · Maine · BBS 2025 Release · 1966–2024

Broad-winged Hawk Population Trend in Maine

All statesGeneralists

Broad-winged Hawk in Maine has surged: up 134% on the route-weighted index since 1971.

+134%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 →
71Routes 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 MaineNotable 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 Maine: up 134% on the route-weighted index since 1971.

Broad-winged Hawk Population Forecast in Maine

If the recent trend holds, Broad-winged Hawk in Maine is projected to fall about 31% by 2029 — from 0.58 in 2024 to a central estimate of 0.40 (95% range 0.11–0.69). A 5-year backtest shows a typical error of ±43.8%, with 40% of held-out values landing inside the 95% band.

-31%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 →
0.40Projected 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 →
0.11–0.6995% 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 →
±43.8%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 Maine is projected to fall about 31% by 2029 — from 0.58 in 2024 to a central estimate of 0.40 (95% range 0.11–0.69). A 5-year backtest shows a typical error of ±43.8%, with 40% of held-out values landing inside the 95% band.19682029
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 →
20250.390.090.68
20260.390.100.68
20270.390.100.68
20280.400.100.69
20290.400.110.69

Broad-winged Hawk Survey Routes in Maine

Routes recording Broad-winged Hawk in Maine.
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 →
Hartford320241975
Benton319791978
Aurora320211976
Topsfield319791979
Northfield 2220181994
Westbrook220241985
Reeds220221993
Otisfield Gr220141980
Freedom220221973
Hermon220191992
Northfield219811978
Moose River220021983
Benedicta220221976
Medway220171977
Forest Sta219791979
Ludlow219961968
Ashland220051991
Cape Neddick120221982
Biddeford119961975
Kittery Pt120071981
Newcastle120081975
Wilson Mills120211983
Bethel120111979
Turner120021973
Greenwood120241974

Broad-winged Hawk Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamarylandmassachusettsmichiganminnesotamississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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