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

Golden-crowned Kinglet In BCR 4

All regionsBCR 4Forest birds

Golden-crowned Kinglet in BCR 4 has surged: up 147% on the route-weighted index since 1986.

+147%Since 1986TrendPercent 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 →
23Routes 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 →
38YearsYears 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 →

Golden-crowned Kinglet has surged in BCR 4: up 147% on the route-weighted index since 1986.

Golden-crowned Kinglet In BCR 4 Population Forecast

If the recent trend holds, Golden-crowned Kinglet in BCR 4 is projected to fall about 22% by 2030 — from 0.51 in 2025 to a central estimate of 0.40 (95% range 0.00–0.82). A 5-year backtest shows a typical error of ±72.5%, with 100% of held-out values landing inside the 95% band.

-22%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 →
0.40Projected 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 →
0.00–0.8295% 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 →
±72.5%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 →
If the recent trend holds, Golden-crowned Kinglet in BCR 4 is projected to fall about 22% by 2030 — from 0.51 in 2025 to a central estimate of 0.40 (95% range 0.00–0.82). A 5-year backtest shows a typical error of ±72.5%, with 100% of held-out values landing inside the 95% band.19822030
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 →
20260.380.000.80
20270.390.000.80
20280.390.000.81
20290.400.000.81
20300.400.000.82

Routes In BCR 4

Routes recording Golden-crowned Kinglet 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 →
KalifonskyALASKA62025
Hatcher PassALASKA42019
Anchor RiverALASKA42018
CohoeALASKA42016
Mccarthy Rd2ALASKA42025
Birch LakeALASKA22021
ChistochinaALASKA22025
HomerALASKA21982
Kenny LakeALASKA22025
PetersvilleALASKA22025
KuskulanaALASKA22025
Skilak LakeALASKA11984
WillowALASKA12025
Swan Lake RdALASKA12024
Chena Hot Spring 2ALASKA12001
Seven LakesALASKA12023
KachemakALASKA12016
Burma RoadALASKA12017
ColdfootALASKA12022
Unalakleet RiverALASKA11999
Murphy DomeALASKA12018
Ft. RichrdsnALASKA12021
Anvik RiverALASKA11998

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