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Species · Oregon · BBS 2026 Release · 1966–2025

Nashville Warbler Population Trend in Oregon

All statesForest birds

Nashville Warbler in Oregon has surged: up 299% on the route-weighted index since 1970.

+299%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 →
65Routes 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 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 299% 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 93% by 2030 — from 1.3 in 2025 to a central estimate of 2.5 (95% range 1.2–3.8). A 5-year backtest shows a typical error of ±53.3%, with 80% of held-out values landing inside the 95% band.

+93%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 →
2.5Projected 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 →
1.2–3.895% 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 →
±53.3%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, Nashville Warbler in Oregon is projected to rise about 93% by 2030 — from 1.3 in 2025 to a central estimate of 2.5 (95% range 1.2–3.8). A 5-year backtest shows a typical error of ±53.3%, 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 →
20262.41.13.7
20272.41.13.7
20282.41.13.7
20292.41.13.8
20302.51.23.8

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 →
Selma2520251993
Secret Val2220251975
Badger Creek1320251993
Prospect1320251993
Days Creek1220251971
Whiskey Spg.1020221992
Molalla920212021
Derby919931978
Sams Valley920251993
Mt Hood820251986
Camp Sherman719941972
Wizard Falls620251998
Cinderella620251993
Warner Mtn.420241992
Ruch420251992
Elkton319911973
Ochoco320241993
Imnaha219731973
Summit Pr220241986
Cool Camp220101968
Winberry220231972
Wedderburn220171972
Bly 2220212010
Scio219751975
Barnes Val219851985

Nashville Warbler Population Trend in Other States

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

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