BirdAnalyst
Species · BCR 5 · BBS 2025 Release · 1966–2024

Willow Flycatcher In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestAerial insectivores

Willow Flycatcher in Northern Pacific Rainforest has fallen sharply: down 66% on the route-weighted index since 1970.

-66%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 →
105Routes 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 →
56YearsYears 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 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 Northern Pacific Rainforest: down 66% on the route-weighted index since 1970.

Forecast

If the recent trend holds, Willow Flycatcher in Northern Pacific Rainforest is projected to fall about 40% by 2029 — from 4.3 in 2024 to a central estimate of 2.6 (95% range 0.00–6.4). A 5-year backtest shows a typical error of ±46.5%, with 100% of held-out values landing inside the 95% band.

-40%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 →
2.6Projected 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 →
0.00–6.495% 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 →
±46.5%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 →
19682029
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 →
20252.90.006.7
20262.80.006.6
20272.70.006.5
20282.70.006.5
20292.60.006.4

Routes In Northern Pacific Rainforest

Routes recording Willow Flycatcher in Northern Pacific Rainforest.
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 →
Mendota 3WASHINGTON462024
IssaquahWASHINGTON361987
Mendota 2WASHINGTON322000
MontesandWASHINGTON312024
MendotaWASHINGTON251988
South ElmaWASHINGTON242024
EverettWASHINGTON232024
LoraneOREGON222024
SantiamOREGON202024
RaymondWASHINGTON192021
McchordWASHINGTON192015
CarnationWASHINGTON162024
GarfieldOREGON152023
Port AngelesWASHINGTON152024
RainierWASHINGTON152019
SvensenOREGON141992
Horse CreekCALIFORNIA122019
MolallaOREGON122024
CougarWASHINGTON122023
Hurricane RgWASHINGTON122024
Cedar FallsWASHINGTON122014
Nicolai Mtn.OREGON112024
MukilteoWASHINGTON112024
FisherOREGON102010
Sandy RiverOREGON102006

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