BirdAnalyst
Species · BCR 28 · BBS 2026 Release · 1966–2025

Willow Flycatcher In Appalachian Mountains

All regionsAppalachian MountainsAerial insectivores

Willow Flycatcher in Appalachian Mountains has surged: up 80% on the route-weighted index since 1968.

+80%Since 1968TrendPercent 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 →
271Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Appalachian Mountains: up 80% on the route-weighted index since 1968.

Willow Flycatcher In Appalachian Mountains Population Forecast

If the recent trend holds, Willow Flycatcher in Appalachian Mountains is projected to rise about 57% by 2030 — from 0.61 in 2025 to a central estimate of 0.96 (95% range 0.41–1.5). A 5-year backtest shows a typical error of ±54.7%, with 100% of held-out values landing inside the 95% band.

+57%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 →
0.96Projected 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 →
0.41–1.595% 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 →
±54.7%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 Appalachian Mountains is projected to rise about 57% by 2030 — from 0.61 in 2025 to a central estimate of 0.96 (95% range 0.41–1.5). A 5-year backtest shows a typical error of ±54.7%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.960.401.5
20270.960.401.5
20280.960.411.5
20290.960.411.5
20300.960.411.5

Routes In Appalachian Mountains

Routes recording Willow Flycatcher in Appalachian Mountains.
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 →
StonecreekOHIO132025
OmegaOHIO112024
Drehersville 2PENNSYLVANIA112025
CumberlandOHIO92017
SmithfieldOHIO82024
JeffersonPENNSYLVANIA82025
RiftonNEW-YORK71986
DrydenNEW-YORK62025
Plesant GrovPENNSYLVANIA62024
DrehersvillePENNSYLVANIA61999
MarionVIRGINIA61982
HebronVIRGINIA62003
S Berne 2NEW-YORK52018
WallerPENNSYLVANIA52025
QuakertownPENNSYLVANIA51989
Mt NeboMARYLAND41989
FinzelMARYLAND42025
SwainNEW-YORK42007
CentervilleNEW-YORK42013
Coal RunOHIO41992
RoulettePENNSYLVANIA42016
BeaverPENNSYLVANIA42025
KaylorPENNSYLVANIA42025
DenmarWEST-VIRGINIA42025
Mt StormWEST-VIRGINIA41975

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