BirdAnalyst
Species · BCR 33 · BBS 2026 Release · 1966–2025

Black-chinned Sparrow In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsArid-land birds

Black-chinned Sparrow in Sonoran and Mojave Deserts has declined: down 48% on the route-weighted index since 1973.

-48%Since 1973TrendPercent 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 →
8Routes 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 →
23YearsYears 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 →

No notable trend signals for Black-chinned Sparrow in Sonoran and Mojave Deserts. See the full index history below.

Black-chinned Sparrow In Sonoran and Mojave Deserts Population Forecast

If the recent trend holds, Black-chinned Sparrow in Sonoran and Mojave Deserts is projected to fall about 37% by 2030 — from 0.07 in 2025 to a central estimate of 0.04 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±61.3%, with 100% of held-out values landing inside the 95% band.

-37%Change by 2030TrendPercent 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 →
0.04Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1495% 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 →
±61.3%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, Black-chinned Sparrow in Sonoran and Mojave Deserts is projected to fall about 37% by 2030 — from 0.07 in 2025 to a central estimate of 0.04 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±61.3%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.050.000.14
20270.050.000.14
20280.050.000.14
20290.050.000.14
20300.040.000.14

Routes In Sonoran and Mojave Deserts

Routes recording Black-chinned 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 →
NelsonNEVADA52010
Cholla Gard.CALIFORNIA32001
BarstowCALIFORNIA21968
Coachella CnCALIFORNIA21973
PearblossomCALIFORNIA22025
OnyxCALIFORNIA11996
Kelso ValleyCALIFORNIA11990
Joshua TreeCALIFORNIA11973

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.