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

Sooty Grouse In Sierra Nevada

All regionsSierra NevadaGeneralists

Sooty Grouse in Sierra Nevada has increased: up 31% on the route-weighted index since 1977.

+31%Since 1977TrendPercent 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 →
16Routes 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 →
34YearsYears 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 Sooty Grouse in Sierra Nevada. See the full index history below.

Sooty Grouse In Sierra Nevada Population Forecast

If the recent trend holds, Sooty Grouse in Sierra Nevada is projected to rise about 197% by 2028 — from 0.06 in 2023 to a central estimate of 0.17 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±147.8%, with 100% of held-out values landing inside the 95% band.

+197%Change by 2028TrendPercent 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 →
0.17Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.4195% 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 →
±147.8%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, Sooty Grouse in Sierra Nevada is projected to rise about 197% by 2028 — from 0.06 in 2023 to a central estimate of 0.17 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±147.8%, with 100% of held-out values landing inside the 95% band.19732028
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 →
20240.170.000.40
20250.170.000.40
20260.170.000.41
20270.170.000.41
20280.170.000.41

Routes In Sierra Nevada

Routes recording Sooty Grouse 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 →
LakeshoreCALIFORNIA52007
GeneseeCALIFORNIA42015
PaxtonCALIFORNIA32007
Hat CreekCALIFORNIA22017
Pine MountainCALIFORNIA21997
Lassen ParkCALIFORNIA11989
Eagle LakeCALIFORNIA11994
WestvilleCALIFORNIA12017
DardanelleCALIFORNIA12008
JohnsvilleCALIFORNIA12022
WoodfordsCALIFORNIA12012
Tuolumne GroveCALIFORNIA11980
RivertonCALIFORNIA11973
Little TruckeeCALIFORNIA12023
Forest HillCALIFORNIA12007
Forest Hill 2CALIFORNIA12005

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