BirdAnalyst
Species · BCR 35 · BBS 2025 Release · 1966–2024

Black-chinned Sparrow In Chihuahuan Desert

All regionsChihuahuan DesertGeneralists

Black-chinned Sparrow in Chihuahuan Desert has edged down: down 21% on the route-weighted index since 1978.

-21%Since 1978TrendPercent 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 →
11Routes 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 →
42YearsYears 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 Chihuahuan Desert. See the full index history below.

Forecast

If the recent trend holds, Black-chinned Sparrow in Chihuahuan Desert is projected to rise about 179% by 2029 — from 0.17 in 2024 to a central estimate of 0.48 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±142.9%, with 100% of held-out values landing inside the 95% band.

+179%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 →
0.48Projected 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 →
0.00–1.195% 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 →
±142.9%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, Black-chinned Sparrow in Chihuahuan Desert is projected to rise about 179% by 2029 — from 0.17 in 2024 to a central estimate of 0.48 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±142.9%, with 100% of held-out values landing inside the 95% band.19742029
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 →
20250.480.001.1
20260.480.001.1
20270.480.001.1
20280.480.001.1
20290.480.001.1

Routes In Chihuahuan Desert

Routes recording Black-chinned Sparrow in Chihuahuan Desert.
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 →
Salt FlatTEXAS92015
GageNEW-MEXICO61974
Capitan Mtn.NEW-MEXICO22017
Bear MtnTEXAS22024
MarfaTEXAS22023
CarrizozoNEW-MEXICO12024
Red RockNEW-MEXICO12009
PinonNEW-MEXICO12024
QueenNEW-MEXICO12021
ToyahvaleTEXAS12009
Chisos BasinTEXAS12024

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