BirdAnalyst
Species · Oregon · BBS 2025 Release · 1966–2024

Warbling Vireo Population Trend in Oregon

All statesForest birds

Warbling Vireo in Oregon has risen sharply: up 70% on the route-weighted index since 1970.

+70%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 →
113Routes 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 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 70% 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 14% by 2029 — from 7.0 in 2024 to a central estimate of 8.0 (95% range 6.4–9.7). A 5-year backtest shows a typical error of ±13.3%, with 100% of held-out values landing inside the 95% band.

+14%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 →
8.0Projected 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 →
6.4–9.795% 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 →
±13.3%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, Warbling Vireo in Oregon is projected to rise about 14% by 2029 — from 7.0 in 2024 to a central estimate of 8.0 (95% range 6.4–9.7). A 5-year backtest shows a typical error of ±13.3%, with 100% 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 →
20257.76.09.3
20267.86.19.4
20277.86.29.5
20287.96.39.6
20298.06.49.7

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 →
Lorane5220241993
Fisher4620101997
Harlan 24420242011
Picture Flat3720241993
Lakeview3720241996
Klickitat Mt3319961993
Salado3220241968
Logdell2920241971
Timber2820171968
Nicolai Mtn.2720241993
Ruch2620231992
Molalla2620241994
Waldport2420011992
Harlan2320092006
Hells Canyon2220221992
Coquille2220241994
Elkton2120241973
Riley Peak2020161994
Svensen1919921990
Santiam1920241994
Wedderburn1820241970
Mt Hood1820241972
Donnelly1820061995
Clearwater1520211991
Sams Valley1420241993

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 2026-05-22.