BirdAnalyst
Species · BCR 5 · BBS 2026 Release · 1966–2025

Chestnut-backed Chickadee In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestForest birds

Chestnut-backed Chickadee in Northern Pacific Rainforest has risen sharply: up 62% on the route-weighted index since 1970.

+62%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 →
145Routes 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 →
57YearsYears 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 →

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 risen sharply in Northern Pacific Rainforest: up 62% on the route-weighted index since 1970.

Chestnut-backed Chickadee In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Chestnut-backed Chickadee in Northern Pacific Rainforest is projected to fall about 25% by 2030 — from 14 in 2025 to a central estimate of 11 (95% range 7.8–14). A 5-year backtest shows a typical error of ±20.6%, with 40% of held-out values landing inside the 95% band.

-25%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 →
11Projected 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 →
7.8–1495% 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 →
±20.6%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 Northern Pacific Rainforest is projected to fall about 25% by 2030 — from 14 in 2025 to a central estimate of 11 (95% range 7.8–14). A 5-year backtest shows a typical error of ±20.6%, with 40% 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 →
2026107.513
2027117.514
2028117.614
2029117.714
2030117.814

Routes In Northern Pacific Rainforest

Routes recording Chestnut-backed Chickadee in Northern Pacific Rainforest.
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 →
ElktonOREGON612025
Crescent CtyCALIFORNIA582025
Vashon Is.WASHINGTON562025
CougarWASHINGTON482023
FisherOREGON472010
Whale PassALASKA442024
RainierWASHINGTON442025
Port AngelesWASHINGTON392025
Thorne Bay 2ALASKA382025
ClearwaterOREGON382025
ZaremboALASKA362024
NeiltonWASHINGTON361975
WedderburnOREGON352025
Mt. AdamsWASHINGTON342025
Hazel CampOREGON332022
RuchOREGON332025
PetersburgALASKA271987
HolmesCALIFORNIA272025
KorbelCALIFORNIA272025
CinderellaOREGON272025
Redwood N.P. 2CALIFORNIA262013
Fish RockCALIFORNIA252014
Bull RunOREGON252025
Warm BeachWASHINGTON242017
IlwacoWASHINGTON242025

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