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Species · Oregon · BBS 2025 Release · 1966–2024

Nashville Warbler Population Trend in Oregon

All statesForest birds

Nashville Warbler in Oregon has surged: up 351% on the route-weighted index since 1970.

+351%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 →
63Routes 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 Nashville Warbler Trends in OregonNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Nashville Warbler has surged in Oregon: up 351% on the route-weighted index since 1970.

Nashville Warbler Population Forecast in Oregon

If the recent trend holds, Nashville Warbler in Oregon is projected to rise about 71% by 2029 — from 1.5 in 2024 to a central estimate of 2.5 (95% range 1.3–3.8). A 5-year backtest shows a typical error of ±55.9%, with 80% of held-out values landing inside the 95% band.

+71%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 →
2.5Projected 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 →
1.3–3.895% 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 →
±55.9%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, Nashville Warbler in Oregon is projected to rise about 71% by 2029 — from 1.5 in 2024 to a central estimate of 2.5 (95% range 1.3–3.8). A 5-year backtest shows a typical error of ±55.9%, with 80% 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 →
20252.41.23.7
20262.51.23.8
20272.51.23.8
20282.51.23.8
20292.51.33.8

Nashville Warbler Survey Routes in Oregon

Routes recording Nashville Warbler in Oregon.
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 →
Clearwater3920211991
Selma3120241993
Ruch2020231992
Prospect1920241993
Cinderella1720241993
Secret Val1620221975
Days Creek1520241971
Badger Creek1220241993
Wizard Falls1120241998
Whiskey Spg.1020221992
Sams Valley1020241993
Molalla920212021
Derby919931978
Camp Sherman719941972
Mt Hood420241986
Hells Canyon420221998
Warner Mtn.420241992
Elkton319911973
Ochoco320241993
Donelly 2320222021
Imnaha219731973
Summit Pr220241986
Cool Camp220101968
Lapham Res.220241992
Winberry220231972

Nashville Warbler Population Trend in Other States

californiaconnecticutidahomainemarylandmassachusettsmichiganminnesotamontananew-hampshirenew-jerseynew-yorknorth-dakotapennsylvaniarhode-islandvermontvirginiawashingtonwest-virginiawisconsin

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