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

Willow Flycatcher Population Trend in Virginia

All statesAerial insectivores

Willow Flycatcher in Virginia has fallen sharply: down 65% on the route-weighted index since 1969.

-65%Since 1969TrendPercent 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 →
33Routes 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 →
54YearsYears 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 VirginiaNotable 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 fallen sharply in Virginia: down 65% on the route-weighted index since 1969.

Willow Flycatcher Population Forecast in Virginia

If the recent trend holds, Willow Flycatcher in Virginia is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.28). A 5-year backtest shows a typical error of ±29.4%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.04Projected 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 →
0.00–0.2895% 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 →
±29.4%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 Virginia is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.28). A 5-year backtest shows a typical error of ±29.4%, with 100% 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 →
20250.060.000.30
20260.060.000.29
20270.050.000.29
20280.050.000.28
20290.040.000.28

Willow Flycatcher Survey Routes in Virginia

Routes recording Willow Flycatcher in Virginia.
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 →
Marion619821976
Hebron620031981
Partlow319801980
Chincoteag W319981998
Putnam219741969
Cape Charles219971997
Taylorstown120071967
W Augusta119951995
Churchville120241967
Stanley119961996
Tryme120191977
Nat Tunnel120001988
Jerome120142014
Rural Retrt120231982
Douthat120041992
David119941994
Isom120051969
Covington120242024
Fincastle119701970
Colonial Pky119971997
Big Island119751975
Carters Brdg119781978
Iron Mtn.120092009
Pine Mtn.120051998
Clinchport119741969

Willow Flycatcher Population Trend in Other States

alaskaarizonaarkansascaliforniacoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontwashingtonwest-virginiawisconsinwyoming

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