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

Chipping Sparrow In BCR 4

All regionsBCR 4Forest birds

Chipping Sparrow in BCR 4 has edged down: down 11% on the route-weighted index since 1990.

-11%Since 1990TrendPercent 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 →
27Routes 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 →
37YearsYears 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 Chipping Sparrow in BCR 4. See the full index history below.

Chipping Sparrow In BCR 4 Population Forecast

If the recent trend holds, Chipping Sparrow in BCR 4 is projected to rise about 43% by 2030 — from 0.59 in 2025 to a central estimate of 0.85 (95% range 0.15–1.6). A 5-year backtest shows a typical error of ±187.3%, with 80% of held-out values landing inside the 95% band.

+43%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 →
0.85Projected 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 →
0.15–1.695% 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 →
±187.3%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, Chipping Sparrow in BCR 4 is projected to rise about 43% by 2030 — from 0.59 in 2025 to a central estimate of 0.85 (95% range 0.15–1.6). A 5-year backtest shows a typical error of ±187.3%, with 80% of held-out values landing inside the 95% band.19872030
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 →
20260.800.101.5
20270.820.111.5
20280.830.121.5
20290.840.141.5
20300.850.151.6

Routes In BCR 4

Routes recording Chipping 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 →
SlanaALASKA112022
SourdoughALASKA52025
Birch LakeALASKA42025
DeltaALASKA42024
ChistochinaALASKA32025
PetersvilleALASKA32025
CircleALASKA22022
Chatanika RALASKA22023
NorthwayALASKA22025
Koyukuk Riv.ALASKA21998
EagleALASKA12025
LivengoodALASKA12012
Tower BluffsALASKA12025
MonahanALASKA11996
Kenny LakeALASKA12024
ChickenALASKA12025
Swan Lake RdALASKA11995
Chena Hot Spring 2ALASKA12025
Lake LouiseALASKA12008
Seven LakesALASKA11995
Donelly DomeALASKA12024
Kanuti CanynALASKA12023
Mt. FairplayALASKA12025
Porcupine R.ALASKA12001
Kanuti LakeALASKA12018

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