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

Willow Flycatcher Population Trend in Kentucky

All statesAerial insectivores

Willow Flycatcher in Kentucky has surged: up 98% on the route-weighted index since 1970.

+98%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 →
24Routes 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 →
53YearsYears 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 KentuckyNotable 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 →

Willow Flycatcher has surged in Kentucky: up 98% on the route-weighted index since 1970.

Willow Flycatcher Population Forecast in Kentucky

If the recent trend holds, Willow Flycatcher in Kentucky is projected to fall about 17% by 2029 — from 0.14 in 2024 to a central estimate of 0.12 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±39.4%, with 80% of held-out values landing inside the 95% band.

-17%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 →
0.12Projected 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 →
0.00–0.2595% 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 →
±39.4%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 Kentucky is projected to fall about 17% by 2029 — from 0.14 in 2024 to a central estimate of 0.12 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±39.4%, with 80% of held-out values landing inside the 95% band.19672029
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 →
20250.120.000.25
20260.120.000.25
20270.120.000.25
20280.120.000.25
20290.120.000.25

Willow Flycatcher Survey Routes in Kentucky

Routes recording Willow Flycatcher in Kentucky.
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 →
Hustonville219681967
Johnsonville220211986
Joy219981986
Goshen219991970
Plum220242008
Keysburg120092009
Cedar Grove119731973
Pleasurevill120242011
Carter120072007
Mcbrayer120092009
Hodgenville120031977
Merrimac120111984
Gatewood120051993
Hudson120231972
Eastview120241967
Glencoe120111992
Buena Vista120011977
Sewell Shop120232023
East Union120051976
Gesling119721972
Kehoe119731972
Bays Fork120192019
Campton119791979
Hodgenville 2120232010

Willow Flycatcher Population Trend in Other States

alaskaarizonaarkansascaliforniacoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansasmainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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