BirdAnalyst
Species · BCR 2 · BBS 2025 Release · 1966–2024

Alder Flycatcher In BCR 2

All regionsBCR 2Aerial insectivores

Alder Flycatcher in BCR 2 has collapsed: down 87% on the route-weighted index since 1993.

-87%Since 1993TrendPercent 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 →
17Routes 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 →
33YearsYears 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 →

Alder Flycatcher has collapsed in BCR 2: down 87% on the route-weighted index since 1993.

Forecast

If the recent trend holds, Alder Flycatcher in BCR 2 is projected to fall about 100% by 2029 — from 0.56 in 2024 to a central estimate of 0.00 (95% range 0.00–4.8). A 5-year backtest shows a typical error of ±176.1%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–4.895% 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 →
±176.1%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, Alder Flycatcher in BCR 2 is projected to fall about 100% by 2029 — from 0.56 in 2024 to a central estimate of 0.00 (95% range 0.00–4.8). A 5-year backtest shows a typical error of ±176.1%, with 100% of held-out values landing inside the 95% band.19862029
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 →
20250.000.004.8
20260.000.004.8
20270.000.004.8
20280.000.004.8
20290.000.004.8

Routes In BCR 2

Routes recording Alder Flycatcher in BCR 2.
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 →
TupuknukALASKA871995
Kugarak (Short)ALASKA351987
Gweek RiverALASKA272002
Selawik (Short)ALASKA151987
CouncilALASKA52023
Kanektok RivALASKA52004
St. Mary'SALASKA42014
KotzebueALASKA42024
DillinghamALASKA22019
Togiak RiverALASKA22005
Katmai N.P.ALASKA12022
ChiniakALASKA12018
King SalmonALASKA12023
NomeALASKA12007
Salmon LakeALASKA12024
TellerALASKA12009
Goodnews BayALASKA12005

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