BirdAnalyst
Species · BCR 13 · BBS 2026 Release · 1966–2025

Willow Flycatcher In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainAerial insectivores

Willow Flycatcher in Lower Great Lakes / St. Lawrence Plain has surged: up 87% on the route-weighted index since 1968.

+87%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 →
84Routes 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 Lower Great Lakes / St. Lawrence Plain: up 87% on the route-weighted index since 1968.

Willow Flycatcher In Lower Great Lakes / St. Lawrence Plain Population Forecast

If the recent trend holds, Willow Flycatcher in Lower Great Lakes / St. Lawrence Plain is projected to rise about 41% by 2030 — from 2.6 in 2025 to a central estimate of 3.6 (95% range 1.5–5.7). A 5-year backtest shows a typical error of ±60.6%, with 100% of held-out values landing inside the 95% band.

+41%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 →
3.6Projected 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 →
1.5–5.795% 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 →
±60.6%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 Lower Great Lakes / St. Lawrence Plain is projected to rise about 41% by 2030 — from 2.6 in 2025 to a central estimate of 3.6 (95% range 1.5–5.7). A 5-year backtest shows a typical error of ±60.6%, 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 →
20263.61.55.7
20273.61.55.7
20283.61.55.7
20293.61.55.7
20303.61.55.7

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Willow Flycatcher in Lower Great Lakes / St. Lawrence Plain.
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 →
WatertownNEW-YORK122012
NashvilleNEW-YORK112018
PittsfieldOHIO102024
GarrettsvileOHIO101991
SheridanNEW-YORK92025
Valley CityOHIO92025
ByronNEW-YORK82025
CayugaNEW-YORK72025
CastileNEW-YORK72025
ChurchvilleNEW-YORK72025
HarmonsburgPENNSYLVANIA72025
SalemNEW-YORK62024
PhiladelphiaNEW-YORK62025
N VictoryNEW-YORK61972
MacdougallNEW-YORK52025
OrleansNEW-YORK52025
BristolVERMONT52000
Oriskany FlsNEW-YORK42025
BranchportNEW-YORK42024
Canadice LNEW-YORK42014
PenfieldNEW-YORK42025
N Victory 2NEW-YORK42019
N WilmurtNEW-YORK41998
WaylandOHIO42017
New SomersetOHIO41993

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