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Species · Oregon · BBS 2025 Release · 1966–2024

Chestnut-backed Chickadee Population Trend in Oregon

All statesForest birds

Chestnut-backed Chickadee in Oregon has surged: up 94% on the route-weighted index since 1970.

+94%Since 1970TrendPercent 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 →
56Routes 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 →
56YearsYears 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 OregonNotable 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 Oregon: up 94% on the route-weighted index since 1970.

Chestnut-backed Chickadee Population Forecast in Oregon

If the recent trend holds, Chestnut-backed Chickadee in Oregon is projected to rise about 28% by 2029 — from 3.1 in 2024 to a central estimate of 3.9 (95% range 2.4–5.4). A 5-year backtest shows a typical error of ±26.6%, with 100% of held-out values landing inside the 95% band.

+28%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 →
3.9Projected 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 →
2.4–5.495% 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 →
±26.6%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 Oregon is projected to rise about 28% by 2029 — from 3.1 in 2024 to a central estimate of 3.9 (95% range 2.4–5.4). A 5-year backtest shows a typical error of ±26.6%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20253.72.25.2
20263.82.35.3
20273.82.35.3
20283.92.45.4
20293.92.45.4

Chestnut-backed Chickadee Survey Routes in Oregon

Routes recording Chestnut-backed Chickadee in Oregon.
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 →
Elkton5220241972
Fisher4720101997
Hazel Camp3320221975
Warner Mtn.2720241992
Clearwater2520211991
Shellrock2320231968
Wedderburn2320241970
Lorane2320241993
Molalla2220241994
Glasgow2120241986
Blue River1720241992
Waldport1620011992
Harlan 21520242012
Winberry1420231968
Klickitat Mt1419961993
Coquille1320241994
Nicolai Mtn.1120241993
Fisher 21120242017
Bull Run1020242007
Garfield1020231975
Harlan1020092006
Sandy River920061993
Svensen819921990
Timber720171969
Santiam720241994

Chestnut-backed Chickadee Population Trend in Other States

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