BirdAnalyst
Species · BCR 4 · BBS 2026 Release · 1966–2025

Rusty Blackbird In BCR 4

All regionsBCR 4Wetland birds

Rusty Blackbird in BCR 4 has fallen sharply: down 51% on the route-weighted index since 1983.

-51%Since 1983TrendPercent 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 →
46Routes 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 →
44YearsYears 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 →

Rusty Blackbird has fallen sharply in BCR 4: down 51% on the route-weighted index since 1983.

Rusty Blackbird In BCR 4 Population Forecast

If the recent trend holds, Rusty Blackbird in BCR 4 is projected to rise about 220% by 2030 — from 0.24 in 2025 to a central estimate of 0.78 (95% range 0.01–1.5). A 5-year backtest shows a typical error of ±105.6%, with 100% of held-out values landing inside the 95% band.

+220%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 →
0.78Projected 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 →
0.01–1.595% 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 →
±105.6%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, Rusty Blackbird in BCR 4 is projected to rise about 220% by 2030 — from 0.24 in 2025 to a central estimate of 0.78 (95% range 0.01–1.5). A 5-year backtest shows a typical error of ±105.6%, with 100% of held-out values landing inside the 95% band.19762030
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 →
20260.800.031.6
20270.790.031.6
20280.790.021.6
20290.780.021.5
20300.780.011.5

Routes In BCR 4

Routes recording Rusty Blackbird in BCR 4.
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 →
Bear CreekALASKA141991
Hather CreekALASKA72024
SlanaALASKA52024
WasillaALASKA41983
Kobuk River (Short)ALASKA41991
Burma RoadALASKA32025
McgrathALASKA32018
Mud RiverALASKA32024
Anvik RiverALASKA32023
Mccarthy Rd2ALASKA32024
CircleALASKA22017
NorthwayALASKA22025
MonahanALASKA22015
Chena Hot SpALASKA21990
Koyukuk Riv.ALASKA22001
Murphy DomeALASKA21998
Ft. RichrdsnALASKA22010
TatalinaALASKA22017
Birch LakeALASKA12021
Tower BluffsALASKA12019
ChistochinaALASKA12023
CantwellALASKA11986
Goose BayALASKA11976
Skilak LakeALASKA11984
HomerALASKA11982

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