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

Red-eyed Vireo Population Trend in Montana

All statesForest birds

Red-eyed Vireo in Montana has declined: down 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 →
43Routes 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 Red-eyed Vireo 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 Red-eyed Vireo in Montana. See the full index history below.

Red-eyed Vireo Population Forecast in Montana

If the recent trend holds, Red-eyed Vireo in Montana is projected to fall about 83% by 2030 — from 0.39 in 2025 to a central estimate of 0.07 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±88%, with 80% of held-out values landing inside the 95% band.

-83%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 →
0.07Projected 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 →
0.00–0.4795% 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%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, Red-eyed Vireo in Montana is projected to fall about 83% by 2030 — from 0.39 in 2025 to a central estimate of 0.07 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±88%, 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 →
20260.100.000.51
20270.090.000.50
20280.080.000.49
20290.070.000.48
20300.070.000.47

Red-eyed Vireo Survey Routes in Montana

Routes recording Red-eyed Vireo 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 →
Swan Lake1320252017
Fish Creek1020241995
Whitefish Lake520242019
Libby Dam420251979
Pagil Gulch420252015
Willow Creek 2219821982
Woodman220241968
Clinton220251975
Two Dot219801980
Red Rock219751975
Ninemile220252004
Noxon220231995
Kalispell120231968
St Mary120081982
Victor120251993
Cleveland119851981
Harlem119801980
St Regis120251980
Arlee120251968
Augusta120211978
Highwood119961972
Brusett119871986
Savage120211995
Elliston119981998
Inside Road120251993

Red-eyed Vireo Population Trend in Other States

alabamaalaskaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsinwyoming

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