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Species · Oregon · BBS 2026 Release · 1966–2025

Warbling Vireo Population Trend in Oregon

All statesForest birds

Warbling Vireo in Oregon has risen sharply: up 69% on the route-weighted index since 1970.

+69%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 →
116Routes 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 Warbling Vireo 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 →

Warbling Vireo has risen sharply in Oregon: up 69% on the route-weighted index since 1970.

Warbling Vireo Population Forecast in Oregon

If the recent trend holds, Warbling Vireo in Oregon is projected to rise about 30% by 2030 — from 6.1 in 2025 to a central estimate of 8.0 (95% range 6.3–9.7). A 5-year backtest shows a typical error of ±17.8%, with 80% of held-out values landing inside the 95% band.

+30%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 →
8.0Projected 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 →
6.3–9.795% 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 →
±17.8%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, Warbling Vireo in Oregon is projected to rise about 30% by 2030 — from 6.1 in 2025 to a central estimate of 8.0 (95% range 6.3–9.7). A 5-year backtest shows a typical error of ±17.8%, 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 →
20267.66.09.3
20277.76.19.4
20287.86.19.5
20297.96.29.6
20308.06.39.7

Warbling Vireo Survey Routes in Oregon

Routes recording Warbling Vireo 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 →
Lorane5520251993
Fisher4620101997
Salado3620251968
Klickitat Mt3319961993
Timber2820171968
Picture Flat2520251993
Lakeview2520251996
Harlan 22520252011
Waldport2420011992
Harlan2320092006
Donelly 22220252018
Molalla2120251994
Logdell2020251971
Hells Canyon2020251992
Riley Peak2020161994
Svensen1919921990
Mt Hood1920251972
Santiam1920251994
Donnelly1820061995
Fisher 21820252017
Elkton1720251973
Wedderburn1620251970
Lobster Creek1520252025
Ochoco1520251993
Mount Vernon1320241986

Warbling Vireo Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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