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Species · Montana · BBS 2026 Release · 1966–2025

Northern Rough-winged Swallow Population Trend in Montana

All statesAerial insectivores

Northern Rough-winged Swallow in Montana has increased: up 50% on the route-weighted index since 1970.

+50%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 Northern Rough-winged 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 Northern Rough-winged Swallow in Montana. See the full index history below.

Northern Rough-winged Swallow Population Forecast in Montana

If the recent trend holds, Northern Rough-winged Swallow in Montana is projected to stay roughly flat through 2030, near 1.5 (95% range 0.51–2.5). A 5-year backtest shows a typical error of ±67.8%, with 80% of held-out values landing inside the 95% band.

-9%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 →
1.5Projected 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 →
0.51–2.595% 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 →
±67.8%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, Northern Rough-winged Swallow in Montana is projected to stay roughly flat through 2030, near 1.5 (95% range 0.51–2.5). A 5-year backtest shows a typical error of ±67.8%, 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 →
20261.50.482.5
20271.50.492.5
20281.50.502.5
20291.50.502.5
20301.50.512.5

Northern Rough-winged Swallow Survey Routes in Montana

Routes recording Northern Rough-winged 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 →
Glen7420251977
Augusta2620251976
St Mary1219821982
St Xavier1220101995
Thompson Riv1020082008
Libby Dam920241979
Savage819901977
Winifred 2820252025
Pablo Res.720241995
Chuffey Spring720242016
Westby520192019
Cabin Creek520232023
Kalispell420251968
Glasgow420252024
Roy419931993
Boulder420251969
Webster419921978
Lindsay420242015
Pryor Mtn.420022000
Ingomar319781978
Lima320251994
Noxon320191998
Raynesford320252019
Clyde Park320252018
Logan Pass320232003

Northern Rough-winged Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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