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

Golden Eagle Population Trend in Montana

All statesBirds of prey

Golden Eagle in Montana has increased: up 38% on the route-weighted index since 1970.

+38%Since 1970TrendPercent 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 →
78Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Golden Eagle Trends in MontanaNotable 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 Golden Eagle in Montana. See the full index history below.

Golden Eagle Population Forecast in Montana

If the recent trend holds, Golden Eagle in Montana is projected to fall about 18% by 2030 — from 0.25 in 2025 to a central estimate of 0.21 (95% range 0.05–0.36). A 5-year backtest shows a typical error of ±55.5%, with 100% of held-out values landing inside the 95% band.

-18%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 →
0.21Projected 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 →
0.05–0.3695% 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 →
±55.5%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, Golden Eagle in Montana is projected to fall about 18% by 2030 — from 0.25 in 2025 to a central estimate of 0.21 (95% range 0.05–0.36). A 5-year backtest shows a typical error of ±55.5%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.210.050.36
20270.210.050.36
20280.210.050.36
20290.210.050.36
20300.210.050.36

Golden Eagle Survey Routes in Montana

Routes recording Golden Eagle in Montana.
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 →
Glen620252001
Lima520251995
Whitlash420182009
Cleveland320151986
Jordan320232016
Chinook320162016
Miles City320232019
Harlem220021993
Polson220231982
Savage219951970
Ingomar220241968
Willow Creek219801972
St Xavier220062006
Powderville220221974
Jordan South220242016
Dinosaurs H.M.220252019
Greenough220001996
Libby Dam119971997
Kalispell119911991
St Mary120041985
Hay Lake120211990
Sunburst120021971
Virgelle120011983
Malta120051976
Redstone119731973

Golden Eagle Population Trend in Other States

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