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

Sora Population Trend in Montana

All statesWetland birds

Sora in Montana has declined: down 36% on the route-weighted index since 1970.

-36%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 →
84Routes 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 Sora 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 Sora in Montana. See the full index history below.

Sora Population Forecast in Montana

If the recent trend holds, Sora in Montana is projected to rise about 94% by 2030 — from 0.22 in 2025 to a central estimate of 0.42 (95% range 0.02–0.83). A 5-year backtest shows a typical error of ±88.2%, with 80% of held-out values landing inside the 95% band.

+94%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 →
0.42Projected 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 →
0.02–0.8395% 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 →
±88.2%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, Sora in Montana is projected to rise about 94% by 2030 — from 0.22 in 2025 to a central estimate of 0.42 (95% range 0.02–0.83). A 5-year backtest shows a typical error of ±88.2%, with 80% 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 →
20260.430.020.83
20270.420.020.83
20280.420.020.83
20290.420.020.83
20300.420.020.83

Sora Survey Routes in Montana

Routes recording Sora 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 →
Westby620252015
Forsyth420181989
St Mary320081973
Harlem320211973
Brusett320231983
East Glacier Park320242018
Jordan South320182018
Hay Lake220191993
Sunburst220071986
Roy220232023
Circle219781978
Elliston220251968
Webster220232023
Red Rock220211974
St. Mary 2220232009
Whitlash220242014
Heart Butte220242015
Chinook220182016
Ester Lake220242015
Saco220242015
Glentana220172015
Swan Lake220192019
Wheat Basin220242018
Chuffey Spring220192018
Libby Dam120101981

Sora Population Trend in Other States

alaskaarizonacaliforniacoloradoidahoillinoisindianaiowakansasmainemassachusettsmichiganminnesotanebraskanevadanew-hampshirenew-mexiconew-yorknorth-dakotaohiooregonpennsylvaniasouth-dakotautahvermontwashingtonwisconsinwyoming

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