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

Willow Flycatcher Population Trend in Oregon

All statesAerial insectivores

Willow Flycatcher in Oregon has collapsed: down 78% on the route-weighted index since 1970.

-78%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 →
98Routes 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 Willow Flycatcher 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 declinecomputed 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 →

Willow Flycatcher has collapsed in Oregon: down 78% on the route-weighted index since 1970.

Willow Flycatcher Population Forecast in Oregon

If the recent trend holds, Willow Flycatcher in Oregon is projected to fall about 64% by 2029 — from 1.8 in 2024 to a central estimate of 0.64 (95% range 0.00–2.8). A 5-year backtest shows a typical error of ±60.1%, with 100% of held-out values landing inside the 95% band.

-64%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 →
0.64Projected 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 →
0.00–2.895% 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 →
±60.1%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, Willow Flycatcher in Oregon is projected to fall about 64% by 2029 — from 1.8 in 2024 to a central estimate of 0.64 (95% range 0.00–2.8). A 5-year backtest shows a typical error of ±60.1%, 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 →
20250.940.003.1
20260.860.003.0
20270.790.003.0
20280.710.002.9
20290.640.002.8

Willow Flycatcher Survey Routes in Oregon

Routes recording Willow Flycatcher 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 →
Fish Lake3420241974
Lorane2220241994
Santiam2020241994
Garfield1520231974
Svensen1419921990
Joseph1220241971
Molalla1220241994
Nicolai Mtn.1120241993
Fisher1020101997
Sandy River1020061993
Scio920241971
Donnelly919951995
Bridgeport820221986
Harlan 2820242011
Blitzen719721971
Pendleton720241978
Umpqua620241968
Timber520171968
Elkton520241972
Bull Run520102007
Glasgow420231990
Troy419971992
Riley Peak420162007
Zumwalt420051995
Cool Camp320131968

Willow Flycatcher Population Trend in Other States

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

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