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

Red-shouldered Hawk In Sierra Nevada

All regionsSierra NevadaGeneralists

Red-shouldered Hawk in Sierra Nevada has surged: up 81% on the route-weighted index since 1981.

+81%Since 1981TrendPercent 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 →
10Routes 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 →
31YearsYears 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 →

Red-shouldered Hawk has surged in Sierra Nevada: up 81% on the route-weighted index since 1981.

Forecast

If the recent trend holds, Red-shouldered Hawk in Sierra Nevada is projected to rise about 87% by 2029 — from 0.16 in 2024 to a central estimate of 0.29 (95% range 0.10–0.49). A 5-year backtest shows a typical error of ±37.1%, with 100% of held-out values landing inside the 95% band.

+87%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 →
0.29Projected 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 →
0.10–0.4995% 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 →
±37.1%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, Red-shouldered Hawk in Sierra Nevada is projected to rise about 87% by 2029 — from 0.16 in 2024 to a central estimate of 0.29 (95% range 0.10–0.49). A 5-year backtest shows a typical error of ±37.1%, with 100% of held-out values landing inside the 95% band.19782029
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 →
20250.270.080.47
20260.280.080.48
20270.280.090.48
20280.290.090.49
20290.290.100.49

Routes In Sierra Nevada

Routes recording Red-shouldered Hawk 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 →
Bass LakeCALIFORNIA52019
Silver CityCALIFORNIA52013
CoultervilleCALIFORNIA22019
Tuolumne GroveCALIFORNIA11999
Higgins CornCALIFORNIA12024
DownievilleCALIFORNIA12007
Hat CreekCALIFORNIA11987
Meadow ValleyCALIFORNIA12014
PlacervilleCALIFORNIA12024
WawonaCALIFORNIA12024

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