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

Cliff Swallow Population Trend in Montana

All statesAerial insectivores

Cliff Swallow in Montana has increased: up 43% on the route-weighted index since 1970.

+43%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 →
103Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Cliff Swallow 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 Cliff Swallow in Montana. See the full index history below.

Cliff Swallow Population Forecast in Montana

If the recent trend holds, Cliff Swallow in Montana is projected to stay roughly flat through 2029, near 18 (95% range 0.00–37). A 5-year backtest shows a typical error of ±6.2%, with 100% of held-out values landing inside the 95% band.

-3%Change by 2029TrendPercent 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 →
18Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–3795% 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 →
±6.2%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, Cliff Swallow in Montana is projected to stay roughly flat through 2029, near 18 (95% range 0.00–37). A 5-year backtest shows a typical error of ±6.2%, with 100% of held-out values landing inside the 95% band.19682029
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 →
2025180.0038
2026180.0038
2027180.0038
2028180.0037
2029180.0037

Cliff Swallow Survey Routes in Montana

Routes recording Cliff Swallow 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 →
St Mary21620081968
Powderville20720241970
Custer 216020242024
Custer14520222022
Beaverhead14220241973
Willow Creek 210920241982
Webster8120241978
Harlem7720211970
Shawmut7520241979
Forsyth7320231980
St. Mary 27320242009
Winnett6520232017
Inside Road6020211999
Whitlash5620242009
St Xavier 25520232017
Redstone5120241969
St Xavier5120111979
Savage5020191970
Greenoagh 35020162015
Jordan South4720212016
Clyde Park4720242018
Heart Butte4520242015
Raynesford4520242016
Albion4220241982
Saco4220242015

Cliff Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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