BirdAnalyst
Species · BCR 35 · BBS 2026 Release · 1966–2025

Rufous-crowned Sparrow In Chihuahuan Desert

All regionsChihuahuan DesertArid-land birds

Rufous-crowned Sparrow in Chihuahuan Desert has risen sharply: up 66% on the route-weighted index since 1969.

+66%Since 1969TrendPercent 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 →
35Routes 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 increasecomputed 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 →

Rufous-crowned Sparrow has risen sharply in Chihuahuan Desert: up 66% on the route-weighted index since 1969.

Rufous-crowned Sparrow In Chihuahuan Desert Population Forecast

If the recent trend holds, Rufous-crowned Sparrow in Chihuahuan Desert is projected to rise about 62% by 2030 — from 1.2 in 2025 to a central estimate of 2.0 (95% range 0.20–3.8). A 5-year backtest shows a typical error of ±172.7%, with 80% of held-out values landing inside the 95% band.

+62%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 →
2.0Projected 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 →
0.20–3.895% 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 →
±172.7%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, Rufous-crowned Sparrow in Chihuahuan Desert is projected to rise about 62% by 2030 — from 1.2 in 2025 to a central estimate of 2.0 (95% range 0.20–3.8). A 5-year backtest shows a typical error of ±172.7%, with 80% of held-out values landing inside the 95% band.19672030
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 →
20261.90.163.7
20272.00.173.7
20282.00.183.7
20292.00.193.8
20302.00.203.8

Routes In Chihuahuan Desert

Routes recording Rufous-crowned 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 →
Devils R CynTEXAS142025
MarfaTEXAS102025
Capitan Mtn.NEW-MEXICO82015
Salt FlatTEXAS62015
ValentineTEXAS51986
Chisos BasinTEXAS52025
PinonNEW-MEXICO42024
LongfellowTEXAS42025
ComstockTEXAS32025
ShafterTEXAS31985
Bear MtnTEXAS32024
Ft. DavisTEXAS32025
CarrizozoNEW-MEXICO22023
GageNEW-MEXICO22023
Lake ValleyNEW-MEXICO22023
Black GapTEXAS22022
OzonaTEXAS22021
LangtryTEXAS21995
CastolonTEXAS22025
PresidioTEXAS22000
CanutilloTEXAS22010
CloudcroftNEW-MEXICO11978
Red RockNEW-MEXICO12023
QueenNEW-MEXICO12021
Hatchet PeakNEW-MEXICO12019

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