BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Song Sparrow In Sierra Nevada

All regionsSierra NevadaGeneralists

Song Sparrow in Sierra Nevada has edged up: up 22% on the route-weighted index since 1973.

+22%Since 1973TrendPercent 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 →
31Routes 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 →
53YearsYears 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 →

No notable trend signals for Song Sparrow in Sierra Nevada. See the full index history below.

Forecast

If the recent trend holds, Song Sparrow in Sierra Nevada is projected to fall about 12% by 2029 — from 4.9 in 2024 to a central estimate of 4.3 (95% range 2.3–6.4). A 5-year backtest shows a typical error of ±23.3%, with 100% of held-out values landing inside the 95% band.

-12%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 →
4.3Projected 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 →
2.3–6.495% 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 →
±23.3%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, Song Sparrow in Sierra Nevada is projected to fall about 12% by 2029 — from 4.9 in 2024 to a central estimate of 4.3 (95% range 2.3–6.4). A 5-year backtest shows a typical error of ±23.3%, with 100% of held-out values landing inside the 95% band.19712029
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 →
20254.12.16.2
20264.22.16.2
20274.22.26.3
20284.32.26.3
20294.32.36.4

Routes In Sierra Nevada

Routes recording Song Sparrow 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 →
GeneseeCALIFORNIA222024
Last ChanceCALIFORNIA152019
ChilcootCALIFORNIA142024
PaxtonCALIFORNIA132024
LakeshoreCALIFORNIA92024
Eagle LakeCALIFORNIA71975
Tuolumne GroveCALIFORNIA72024
DownievilleCALIFORNIA72024
JohnsvilleCALIFORNIA52024
WoodfordsCALIFORNIA52024
Butte MeadowCALIFORNIA52014
Meadow ValleyCALIFORNIA52024
Little TruckeeCALIFORNIA52023
KernvilleCALIFORNIA32008
Lassen ParkCALIFORNIA21987
Cottage SpgsCALIFORNIA21974
Kings CanyonCALIFORNIA22024
Higgins CornCALIFORNIA22024
DardanelleCALIFORNIA12019
Bass LakeCALIFORNIA12018
Greenhorn MtCALIFORNIA11990
Silver CityCALIFORNIA12013
SattleyCALIFORNIA12024
RivertonCALIFORNIA12023
Hat CreekCALIFORNIA12018

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