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

American Goshawk In Sierra Nevada

All regionsSierra NevadaGeneralists

American Goshawk in Sierra Nevada has declined: down 38% on the route-weighted index since 1979.

-38%Since 1979TrendPercent 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 →
18Routes 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 →
28YearsYears 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 American Goshawk in Sierra Nevada. See the full index history below.

American Goshawk In Sierra Nevada Population Forecast

If the recent trend holds, American Goshawk in Sierra Nevada is projected to fall about 20% by 2028 — from 0.06 in 2023 to a central estimate of 0.05 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±36.3%, with 100% of held-out values landing inside the 95% band.

-20%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 →
0.05Projected 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 →
0.00–0.1395% 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 →
±36.3%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, American Goshawk in Sierra Nevada is projected to fall about 20% by 2028 — from 0.06 in 2023 to a central estimate of 0.05 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±36.3%, with 100% of held-out values landing inside the 95% band.19742028
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 →
20240.050.000.13
20250.050.000.13
20260.050.000.13
20270.050.000.13
20280.050.000.13

Routes In Sierra Nevada

Routes recording American Goshawk 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 →
Eagle LakeCALIFORNIA12021
WestvilleCALIFORNIA12022
JohnsvilleCALIFORNIA12017
WoodfordsCALIFORNIA12023
LumberyardCALIFORNIA12006
Greenhorn MtCALIFORNIA11986
Tuolumne GroveCALIFORNIA12011
Butte MeadowCALIFORNIA11980
GeneseeCALIFORNIA11993
RivertonCALIFORNIA12012
Hat CreekCALIFORNIA12004
LakeshoreCALIFORNIA12001
Chaos CraterCALIFORNIA12000
Meadow ValleyCALIFORNIA12017
Little TruckeeCALIFORNIA12001
Pollock PinesCALIFORNIA12014
CoultervilleCALIFORNIA12012
Pine MountainCALIFORNIA12003

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