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Species · Wyoming · BBS 2026 Release · 1966–2025

Willow Flycatcher Population Trend in Wyoming

All statesAerial insectivores

Willow Flycatcher in Wyoming has edged down: down 21% on the route-weighted index since 1970.

-21%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 →
55Routes 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 →
52YearsYears 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 WyomingNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Willow Flycatcher in Wyoming. See the full index history below.

Willow Flycatcher Population Forecast in Wyoming

If the recent trend holds, Willow Flycatcher in Wyoming is projected to fall about 51% by 2030 — from 0.53 in 2025 to a central estimate of 0.26 (95% range 0.00–0.92). A 5-year backtest shows a typical error of ±38.5%, with 100% of held-out values landing inside the 95% band.

-51%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 →
0.26Projected 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 →
0.00–0.9295% 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 →
±38.5%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 Wyoming is projected to fall about 51% by 2030 — from 0.53 in 2025 to a central estimate of 0.26 (95% range 0.00–0.92). A 5-year backtest shows a typical error of ±38.5%, with 100% 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 →
20260.290.000.95
20270.280.000.94
20280.280.000.94
20290.270.000.93
20300.260.000.92

Willow Flycatcher Survey Routes in Wyoming

Routes recording Willow Flycatcher in Wyoming.
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 →
Moskee1320001989
Wilson1220251980
Dayton1120251980
Buckskin Mtn520251980
Alpine420251979
Moskee 2420132002
Fontenelle320251982
Meeteetse320252011
Mayoworth320181997
Soda Lake320251981
Green River319821977
Otto220042004
Colter Bay219981968
Midvale220252025
Redbird219791979
Mammoth220212015
Hunter Peak219931989
Colter Bay 2220252019
Seedskadee220232023
Boulder220091982
Big Sandy220222005
Fiddler Lk220241990
Walcott220251989
Ne Entrance120251988
Cody120241997

Willow Flycatcher Population Trend in Other States

alaskaarizonaarkansascaliforniacoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsin

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