BirdAnalyst
Species · BCR 33 · BBS 2025 Release · 1966–2024

Prairie Falcon In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsGeneralists

Prairie Falcon in Sonoran and Mojave Deserts has fallen sharply: down 73% on the route-weighted index since 1971.

-73%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 →
46Routes 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 →
49YearsYears 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 →

Prairie Falcon has fallen sharply in Sonoran and Mojave Deserts: down 73% on the route-weighted index since 1971.

Prairie Falcon In Sonoran and Mojave Deserts Population Forecast

If the recent trend holds, Prairie Falcon in Sonoran and Mojave Deserts is projected to fall about 15% by 2029 — from 0.07 in 2024 to a central estimate of 0.06 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±77.7%, with 80% of held-out values landing inside the 95% band.

-15%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 →
0.06Projected 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 →
0.00–0.1795% 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 →
±77.7%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 Sonoran and Mojave Deserts is projected to fall about 15% by 2029 — from 0.07 in 2024 to a central estimate of 0.06 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±77.7%, with 80% 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 →
20250.060.000.18
20260.060.000.18
20270.060.000.17
20280.060.000.17
20290.060.000.17

Routes In Sonoran and Mojave Deserts

Routes recording Prairie Falcon in Sonoran and Mojave Deserts.
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 →
TronaCALIFORNIA21995
Coachella CnCALIFORNIA21975
Joshua TreeCALIFORNIA22002
Cholla Gard.CALIFORNIA22009
Squaw PeakARIZONA11969
OatmanARIZONA11995
QuartzsiteARIZONA12018
VicksburgARIZONA11977
LagunaARIZONA12022
DatelandARIZONA12012
AjoARIZONA12000
LukevilleARIZONA11980
Cibola LakeARIZONA12018
Gila BendARIZONA12022
ArabyARIZONA12002
Cabeza PrietARIZONA12018
Casa GrandeARIZONA12008
Cactus ForestARIZONA12016
Cutter 2ARIZONA12017
Hope 2ARIZONA12019
UbehebeCALIFORNIA12021
Haiwee ResCALIFORNIA12004
OnyxCALIFORNIA12001
GoldstoneCALIFORNIA12006
Willow SpgsCALIFORNIA11981

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