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

Horned Lark Population Trend in Montana

All statesGrassland birds

Horned Lark in Montana has held roughly steady: up 3% on the route-weighted index since 1970.

+3%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 →
87Routes 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 Horned Lark 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 Horned Lark in Montana. See the full index history below.

Horned Lark Population Forecast in Montana

If the recent trend holds, Horned Lark in Montana is projected to fall about 31% by 2030 — from 43 in 2025 to a central estimate of 29 (95% range 0.00–61). A 5-year backtest shows a typical error of ±32.3%, with 100% of held-out values landing inside the 95% band.

-31%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 →
29Projected 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 →
0.00–6195% 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 →
±32.3%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, Horned Lark in Montana is projected to fall about 31% by 2030 — from 43 in 2025 to a central estimate of 29 (95% range 0.00–61). A 5-year backtest shows a typical error of ±32.3%, 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 →
2026310.1363
2027310.0062
2028300.0062
2029300.0061
2030290.0061

Horned Lark Survey Routes in Montana

Routes recording Horned Lark 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 →
Glasgow41420251968
Oswego34420251978
Virgelle28620251979
Coleman Coulee26920242017
Circle21620231969
Gildford21120252015
Dinosaurs H.M.20920252018
Shelby20620252015
Westby17520252015
Redstone16920251968
Harlem16220211968
Sunburst14720071968
Glentana14120252015
Jordan South12920252016
Lambert12420252021
Ester Lake10320252015
Great Falls9420251972
Jordan8920241968
Saco8720252015
Chinook8020252015
Whitlash7820242009
Hay Lake6620251988
Wolf Point6020242015
Church Hill5820252017
Glen5020251977

Horned Lark Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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