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

American Kestrel In Sierra Nevada

All regionsSierra NevadaGeneralists

American Kestrel in Sierra Nevada has fallen sharply: down 58% on the route-weighted index since 1971.

-58%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 →
32Routes 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 →
54YearsYears 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 declinecomputed 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 →

American Kestrel has fallen sharply in Sierra Nevada: down 58% on the route-weighted index since 1971.

American Kestrel In Sierra Nevada Population Forecast

If the recent trend holds, American Kestrel in Sierra Nevada is projected to fall about 79% by 2029 — from 0.68 in 2024 to a central estimate of 0.15 (95% range 0.00–0.53). A 5-year backtest shows a typical error of ±62.2%, with 60% of held-out values landing inside the 95% band.

-79%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 →
0.15Projected 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 →
0.00–0.5395% 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 →
±62.2%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 Kestrel in Sierra Nevada is projected to fall about 79% by 2029 — from 0.68 in 2024 to a central estimate of 0.15 (95% range 0.00–0.53). A 5-year backtest shows a typical error of ±62.2%, with 60% 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 →
20250.170.000.56
20260.170.000.55
20270.160.000.54
20280.150.000.54
20290.150.000.53

Routes In Sierra Nevada

Routes recording American Kestrel 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 →
ChilcootCALIFORNIA42024
SattleyCALIFORNIA32024
Butte MeadowCALIFORNIA31990
Last ChanceCALIFORNIA32019
Lassen ParkCALIFORNIA21976
Bass LakeCALIFORNIA22019
WoodfordsCALIFORNIA22024
Greenhorn MtCALIFORNIA21997
Hat CreekCALIFORNIA22018
GoumazCALIFORNIA22007
PaxtonCALIFORNIA22017
Eagle LakeCALIFORNIA12024
WestvilleCALIFORNIA12024
DardanelleCALIFORNIA11997
JohnsvilleCALIFORNIA12015
LumberyardCALIFORNIA11981
Silver CityCALIFORNIA12013
Kings CanyonCALIFORNIA12009
Tuolumne GroveCALIFORNIA12024
GeneseeCALIFORNIA12024
Higgins CornCALIFORNIA11982
DownievilleCALIFORNIA11984
RivertonCALIFORNIA12008
LakeshoreCALIFORNIA11980
Little TruckeeCALIFORNIA12009

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