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

Western Screech-Owl In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsGeneralists

Western Screech-Owl in Sonoran and Mojave Deserts has fallen sharply: down 59% on the route-weighted index since 1992.

-59%Since 1992TrendPercent 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 →
13Routes 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 →
19YearsYears 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 →

Western Screech-Owl has fallen sharply in Sonoran and Mojave Deserts: down 59% on the route-weighted index since 1992.

Western Screech-Owl In Sonoran and Mojave Deserts Population Forecast

If the recent trend holds, Western Screech-Owl in Sonoran and Mojave Deserts is projected to stay roughly flat through 2028, near 0.02 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±17.2%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.02Projected 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 →
0.00–0.0795% 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 →
±17.2%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, Western Screech-Owl in Sonoran and Mojave Deserts is projected to stay roughly flat through 2028, near 0.02 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±17.2%, with 100% of held-out values landing inside the 95% band.19732028
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 →
20240.030.000.07
20250.030.000.07
20260.030.000.07
20270.030.000.07
20280.020.000.07

Routes In Sonoran and Mojave Deserts

Routes recording Western Screech-Owl 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 →
WikieupARIZONA11997
LagunaARIZONA11985
RivieraARIZONA12011
Alamo Res.ARIZONA12021
Gila BendARIZONA12002
Red RockARIZONA12014
Casa GrandeARIZONA12011
Ajo 2ARIZONA12019
Cactus ForestARIZONA12005
Organ PipeARIZONA12003
Cutter 2ARIZONA12015
Palo VerdeCALIFORNIA12013
Kelso ValleyCALIFORNIA12023

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