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

American Goshawk Population Trend in Maine

All statesGeneralists

American Goshawk in Maine has edged up: up 23% on the route-weighted index since 1983.

+23%Since 1983TrendPercent 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 →
15Routes 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 →
18YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable American Goshawk 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 →

No notable trend signals for American Goshawk in Maine. See the full index history below.

American Goshawk Population Forecast in Maine

If the recent trend holds, American Goshawk in Maine is projected to fall about 51% by 2022 — from 0.07 in 2017 to a central estimate of 0.04 (95% range 0.01–0.07). A 5-year backtest shows a typical error of ±25%, with 80% of held-out values landing inside the 95% band.

-51%Change by 2022TrendPercent 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 →
0.04Projected 2022 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.01–0.0795% 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 →
±25%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, American Goshawk in Maine is projected to fall about 51% by 2022 — from 0.07 in 2017 to a central estimate of 0.04 (95% range 0.01–0.07). A 5-year backtest shows a typical error of ±25%, with 80% of held-out values landing inside the 95% band.19792022
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 →
20180.040.010.07
20190.040.010.07
20200.040.010.07
20210.040.010.07
20220.040.010.07

American Goshawk Survey Routes in Maine

Routes recording American Goshawk 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 →
Charleston120051989
Greenville120172017
Wilson Mills120131985
Bethel119881988
Medway119791979
Reeds120072007
South Arm119901990
Hartford119811981
Bowdoin Ctr119991999
Clayton Lake119851985
Rome120011999
Heron Lake119831983
Jefferson119961996
Eastbrook120172017
Carrying Pl120092000

American Goshawk Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahomassachusettsmichiganminnesotamontananevadanew-hampshirenew-jerseynew-mexiconew-yorkoregonpennsylvaniarhode-islandsouth-dakotautahvermontwashingtonwisconsinwyoming

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