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

House Sparrow In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsGeneralists

House Sparrow in Sonoran and Mojave Deserts has fallen sharply: down 58% on the route-weighted index since 1970.

-58%Since 1970TrendPercent 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 →
74Routes 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 →
56YearsYears 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 →

House Sparrow has fallen sharply in Sonoran and Mojave Deserts: down 58% on the route-weighted index since 1970.

Forecast

If the recent trend holds, House Sparrow in Sonoran and Mojave Deserts is projected to fall about 60% by 2029 — from 11 in 2024 to a central estimate of 4.4 (95% range 0.00–25). A 5-year backtest shows a typical error of ±31.9%, with 100% of held-out values landing inside the 95% band.

-60%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 →
4.4Projected 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 →
0.00–2595% 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 →
±31.9%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, House Sparrow in Sonoran and Mojave Deserts is projected to fall about 60% by 2029 — from 11 in 2024 to a central estimate of 4.4 (95% range 0.00–25). A 5-year backtest shows a typical error of ±31.9%, 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 →
20257.60.0028
20266.80.0028
20276.00.0027
20285.20.0026
20294.40.0025

Routes In Sonoran and Mojave Deserts

Routes recording House Sparrow 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 →
CoolidgeARIZONA1451985
New RiverARIZONA1072016
Willow SpgsCALIFORNIA951981
Joshua Tree 2CALIFORNIA902016
Jean LakeNEVADA862013
Willow Springs 2CALIFORNIA722024
BeattyNEVADA702021
LenwoodCALIFORNIA662012
FlorenceARIZONA641988
Joshua TreeCALIFORNIA632002
TronaCALIFORNIA571997
InyokernCALIFORNIA552024
Cactus ForestARIZONA542024
Imperial DamCALIFORNIA512010
BarstowCALIFORNIA441998
PearblossomCALIFORNIA312024
VicksburgARIZONA301989
LagunaARIZONA302023
Red Rock 2ARIZONA262024
Palo VerdeARIZONA252013
CadizCALIFORNIA241992
Coachella CnCALIFORNIA222013
Ajo 2ARIZONA212022
Calif CityCALIFORNIA212015
Ft IrwinCALIFORNIA191982

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