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

California Quail In Sierra Nevada

All regionsSierra NevadaGeneralists

California Quail in Sierra Nevada has declined: down 47% on the route-weighted index since 1971.

-47%Since 1971TrendPercent 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 →
28Routes 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 →
55YearsYears 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 California Quail in Sierra Nevada. See the full index history below.

California Quail In Sierra Nevada Population Forecast

If the recent trend holds, California Quail in Sierra Nevada is projected to rise about 70% by 2029 — from 1.9 in 2024 to a central estimate of 3.3 (95% range 0.83–5.8). A 5-year backtest shows a typical error of ±73.1%, with 100% of held-out values landing inside the 95% band.

+70%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 →
3.3Projected 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 →
0.83–5.895% 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 →
±73.1%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, California Quail in Sierra Nevada is projected to rise about 70% by 2029 — from 1.9 in 2024 to a central estimate of 3.3 (95% range 0.83–5.8). A 5-year backtest shows a typical error of ±73.1%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20253.30.785.8
20263.30.795.8
20273.30.805.8
20283.30.815.8
20293.30.835.8

Routes In Sierra Nevada

Routes recording California Quail 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 →
Last ChanceCALIFORNIA252019
WawonaCALIFORNIA192024
Bass LakeCALIFORNIA132019
CoultervilleCALIFORNIA122019
Greenhorn MtCALIFORNIA92008
Butte MeadowCALIFORNIA91990
ChilcootCALIFORNIA62024
Cottage SpgsCALIFORNIA51975
WoodfordsCALIFORNIA52024
KernvilleCALIFORNIA42008
Eagle LakeCALIFORNIA32007
WestvilleCALIFORNIA32006
PaxtonCALIFORNIA32024
Forest HillCALIFORNIA32022
Silver CityCALIFORNIA22013
Kings CanyonCALIFORNIA22016
Meadow ValleyCALIFORNIA22018
Little TruckeeCALIFORNIA22023
JohnsvilleCALIFORNIA12024
Tuolumne GroveCALIFORNIA12010
SattleyCALIFORNIA12024
GeneseeCALIFORNIA12024
Higgins CornCALIFORNIA12024
RivertonCALIFORNIA12001
Hat CreekCALIFORNIA12018

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