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Species · Montana · BBS 2025 Release · 1966–2024

Chestnut-backed Chickadee Population Trend in Montana

All statesForest birds

Chestnut-backed Chickadee in Montana has increased: up 39% on the route-weighted index since 1988.

+39%Since 1988TrendPercent 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 →
11Routes 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 →
35YearsYears 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 MontanaNotable 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 Chestnut-backed Chickadee in Montana. See the full index history below.

Chestnut-backed Chickadee Population Forecast in Montana

If the recent trend holds, Chestnut-backed Chickadee in Montana is projected to rise about 55% by 2029 — from 0.09 in 2024 to a central estimate of 0.15 (95% range 0.02–0.27). A 5-year backtest shows a typical error of ±34.4%, with 100% of held-out values landing inside the 95% band.

+55%Change by 2029TrendPercent 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 →
0.15Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.02–0.2795% 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 →
±34.4%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 Montana is projected to rise about 55% by 2029 — from 0.09 in 2024 to a central estimate of 0.15 (95% range 0.02–0.27). A 5-year backtest shows a typical error of ±34.4%, with 100% of held-out values landing inside the 95% band.19862029
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 →
20250.140.020.27
20260.140.020.27
20270.140.020.27
20280.140.020.27
20290.150.020.27

Chestnut-backed Chickadee Survey Routes in Montana

Routes recording Chestnut-backed Chickadee in Montana.
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 →
Logan Pass320231988
Noxon320232004
St Regis320241988
Fish Creek220222022
Inside Road120061993
Libby Dam120241989
Whitefish Lake120242016
Arlee120241986
Swan Lake120232015
Woodman120242016
Thompson Riv120242006

Chestnut-backed Chickadee Population Trend in Other States

alaskacaliforniaidahooregonwashington

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.