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Species · Montana · BBS 2026 Release · 1966–2025

Swainson's Hawk Population Trend in Montana

All statesBirds of prey

Swainson's Hawk in Montana has surged: up 683% on the route-weighted index since 1970.

+683%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 Swainson's Hawk 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 →

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 →

Swainson's Hawk has surged in Montana: up 683% on the route-weighted index since 1970.

Swainson's Hawk Population Forecast in Montana

If the recent trend holds, Swainson's Hawk in Montana is projected to rise about 35% by 2030 — from 0.78 in 2025 to a central estimate of 1.1 (95% range 0.48–1.6). A 5-year backtest shows a typical error of ±20.5%, with 100% of held-out values landing inside the 95% band.

+35%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 →
1.1Projected 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 →
0.48–1.695% 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 →
±20.5%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, Swainson's Hawk in Montana is projected to rise about 35% by 2030 — from 0.78 in 2025 to a central estimate of 1.1 (95% range 0.48–1.6). A 5-year backtest shows a typical error of ±20.5%, 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 →
20261.00.431.6
20271.00.441.6
20281.00.451.6
20291.00.471.6
20301.10.481.6

Swainson's Hawk Survey Routes in Montana

Routes recording Swainson's Hawk 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 →
Circle1020211969
Whitlash1020242009
Coleman Coulee720242017
Harlem620211981
Boulder620252019
Shelby620252015
Church Hill520252017
Hay Lake320241988
Sunburst320071970
Glasgow320251970
Flatwillow320061968
Gildford320252016
Chuffey Spring320192016
Virgelle220251979
Cleveland220251979
Malta220251976
Oswego220251978
Redstone220251969
Great Falls220251973
Roy220231988
Brusett220112001
Jordan220241982
Ingomar220251970
Locate220061988
Laurel220171996

Swainson's Hawk Population Trend in Other States

alaskaarizonaarkansascaliforniacoloradoidahoillinoisiowakansaslouisianaminnesotamissourinebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwisconsinwyoming

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