BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Prairie Falcon In Great Basin

All regionsGreat BasinGeneralists

Prairie Falcon in Great Basin has surged: up 103% on the route-weighted index since 1971.

+103%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 →
180Routes 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 →

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 →

Prairie Falcon has surged in Great Basin: up 103% on the route-weighted index since 1971.

Prairie Falcon In Great Basin Population Forecast

If the recent trend holds, Prairie Falcon in Great Basin is projected to rise about 11% by 2029 — from 0.29 in 2024 to a central estimate of 0.32 (95% range 0.20–0.44). A 5-year backtest shows a typical error of ±27.7%, with 100% of held-out values landing inside the 95% band.

+11%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 →
0.32Projected 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 →
0.20–0.4495% 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 →
±27.7%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, Prairie Falcon in Great Basin is projected to rise about 11% by 2029 — from 0.29 in 2024 to a central estimate of 0.32 (95% range 0.20–0.44). A 5-year backtest shows a typical error of ±27.7%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20250.300.180.42
20260.310.180.43
20270.310.190.43
20280.310.190.43
20290.320.200.44

Routes In Great Basin

Routes recording Prairie Falcon in Great Basin.
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 →
Catlow RimOREGON72024
GandyUTAH62015
Dinner StaNEVADA41993
Virgin CreekNEVADA42018
ImnahaOREGON42023
Indian PeakUTAH42016
Tule ValleyUTAH42012
Moses CouleeWASHINGTON42023
PrestonIDAHO32018
Battle MtnOREGON32017
Green Mtn.OREGON32024
Fish SpringsUTAH32017
RavendaleCALIFORNIA22008
DorrisCALIFORNIA22018
MacdoelCALIFORNIA22018
LeadoreIDAHO22024
Pasadena ValIDAHO22004
Blackft ResIDAHO21989
Calico SprNEVADA21974
SutcliffeNEVADA21971
Majors PlaceNEVADA22017
GardnervilleNEVADA21995
Gardnerville 2NEVADA22015
Lone RockOREGON22024
BlitzenOREGON21993

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