BirdAnalyst
Species · BCR 15 · BBS 2026 Release · 1966–2025

Mountain Chickadee In Sierra Nevada

All regionsSierra NevadaForest birds

Mountain Chickadee in Sierra Nevada has risen sharply: up 61% on the route-weighted index since 1970.

+61%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 →
38Routes 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 →

Mountain Chickadee has risen sharply in Sierra Nevada: up 61% on the route-weighted index since 1970.

Mountain Chickadee In Sierra Nevada Population Forecast

If the recent trend holds, Mountain Chickadee in Sierra Nevada is projected to rise about 20% by 2030 — from 15 in 2025 to a central estimate of 19 (95% range 6.7–30). A 5-year backtest shows a typical error of ±16.1%, with 100% of held-out values landing inside the 95% band.

+20%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 →
19Projected 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 →
6.7–3095% 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 →
±16.1%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, Mountain Chickadee in Sierra Nevada is projected to rise about 20% by 2030 — from 15 in 2025 to a central estimate of 19 (95% range 6.7–30). A 5-year backtest shows a typical error of ±16.1%, with 100% 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 →
2026197.231
2027197.131
2028197.031
2029196.830
2030196.730

Routes In Sierra Nevada

Routes recording Mountain Chickadee in Sierra Nevada.
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 →
GoumazCALIFORNIA612011
Pine MountainCALIFORNIA552017
ChilcootCALIFORNIA452024
Lassen ParkCALIFORNIA441989
Last ChanceCALIFORNIA442019
Greenhorn MtCALIFORNIA372008
Eagle LakeCALIFORNIA342025
Little TruckeeCALIFORNIA332025
LumberyardCALIFORNIA322025
Meadow ValleyCALIFORNIA302025
ChesterCALIFORNIA292017
Hat CreekCALIFORNIA282018
LakeshoreCALIFORNIA272024
JohnsvilleCALIFORNIA262025
WestvilleCALIFORNIA252025
CrestviewCALIFORNIA232025
GeneseeCALIFORNIA192024
Tahoe NfCALIFORNIA191994
Cottage SpgsCALIFORNIA181975
RivertonCALIFORNIA182025
WoodfordsCALIFORNIA172025
Butte MeadowCALIFORNIA172014
StrawberryCALIFORNIA172019
SattleyCALIFORNIA152025
Forest Hill 2CALIFORNIA132005

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