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Species · Idaho · BBS 2026 Release · 1966–2025

Chestnut-backed Chickadee Population Trend in Idaho

All statesForest birds

Chestnut-backed Chickadee in Idaho has surged: up 219% on the route-weighted index since 1979.

+219%Since 1979TrendPercent 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 →
15Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
43YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Chestnut-backed Chickadee Trends in IdahoNotable 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 →

Chestnut-backed Chickadee has surged in Idaho: up 219% on the route-weighted index since 1979.

Chestnut-backed Chickadee Population Forecast in Idaho

If the recent trend holds, Chestnut-backed Chickadee in Idaho is projected to rise about 21% by 2030 — from 1.2 in 2025 to a central estimate of 1.4 (95% range 0.77–2.1). A 5-year backtest shows a typical error of ±20%, with 100% of held-out values landing inside the 95% band.

+21%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 →
1.4Projected 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 →
0.77–2.195% 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 →
±20%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, Chestnut-backed Chickadee in Idaho is projected to rise about 21% by 2030 — from 1.2 in 2025 to a central estimate of 1.4 (95% range 0.77–2.1). A 5-year backtest shows a typical error of ±20%, with 100% of held-out values landing inside the 95% band.19772030
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 →
20261.30.682.0
20271.40.702.0
20281.40.722.0
20291.40.752.0
20301.40.772.1

Chestnut-backed Chickadee Survey Routes in Idaho

Routes recording Chestnut-backed Chickadee in Idaho.
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 →
Coolin1320251986
N Fork Cda R1220191993
Pierce1020071995
Grangeville920251994
Naples820251978
Baldy Mountain620142013
Mivoden520251977
Marble Creek520251988
Lolo Pass320191993
Nezperce220081995
Avery120231991
Golden120132003
Rochat Divde120251994
Nezperce Nf119981998
Salmon River120091990

Chestnut-backed Chickadee Population Trend in Other States

alaskacaliforniamontanaoregonwashington

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