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

White-crowned Sparrow In BCR 4

All regionsBCR 4Forest birds

White-crowned Sparrow in BCR 4 has held roughly steady: down 10% on the route-weighted index since 1976.

-10%Since 1976TrendPercent 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 →
70Routes 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 →
48YearsYears 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 →

No notable trend signals for White-crowned Sparrow in BCR 4. See the full index history below.

White-crowned Sparrow In BCR 4 Population Forecast

If the recent trend holds, White-crowned Sparrow in BCR 4 is projected to fall about 12% by 2030 — from 34 in 2025 to a central estimate of 30 (95% range 16–44). A 5-year backtest shows a typical error of ±15%, with 100% of held-out values landing inside the 95% band.

-12%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 →
30Projected 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 →
16–4495% 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 →
±15%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, White-crowned Sparrow in BCR 4 is projected to fall about 12% by 2030 — from 34 in 2025 to a central estimate of 30 (95% range 16–44). A 5-year backtest shows a typical error of ±15%, with 100% of held-out values landing inside the 95% band.19682030
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 →
2026311745
2027311745
2028311645
2029301644
2030301644

Routes In BCR 4

Routes recording White-crowned Sparrow 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 →
DeltaALASKA1122024
SavageALASKA982025
ToklatALASKA962024
MaclarenALASKA942025
CantwellALASKA892025
Caribou Mtn.ALASKA762025
Lake LouiseALASKA752025
EagleALASKA722025
MonahanALASKA712025
Mt. FairplayALASKA672025
Nabesna RoadALASKA642025
KuskulanaALASKA632025
ChickenALASKA572025
WasillaALASKA441983
Paxson LakeALASKA441997
Chatanika RALASKA422025
Seven LakesALASKA422025
Kanuti LakeALASKA422024
McgrathALASKA402022
Mccarthy Rd2ALASKA392025
Goose BayALASKA361982
Moose CreekALASKA362022
PetersvilleALASKA332025
Skilak LakeALASKA321985
Hatcher PassALASKA322025

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