BirdAnalyst
Species · BCR 18 · BBS 2026 Release · 1966–2025

Rufous-crowned Sparrow In Shortgrass Prairie

All regionsShortgrass PrairieArid-land birds

Rufous-crowned Sparrow in Shortgrass Prairie has collapsed: down 81% on the route-weighted index since 1970.

-81%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 →
14Routes 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 →
55YearsYears 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 →

Rufous-crowned Sparrow has collapsed in Shortgrass Prairie: down 81% on the route-weighted index since 1970.

Rufous-crowned Sparrow In Shortgrass Prairie Population Forecast

If the recent trend holds, Rufous-crowned Sparrow in Shortgrass Prairie is projected to stay roughly flat through 2030, near 0.07 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±305.9%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.07Projected 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 →
0.00–0.2195% 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 →
±305.9%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, Rufous-crowned Sparrow in Shortgrass Prairie is projected to stay roughly flat through 2030, near 0.07 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±305.9%, 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 →
20260.080.000.22
20270.080.000.22
20280.070.000.22
20290.070.000.22
20300.070.000.21

Routes In Shortgrass Prairie

Routes recording Rufous-crowned Sparrow in Shortgrass Prairie.
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 →
Wagon MoundNEW-MEXICO51974
VariaderoNEW-MEXICO32022
DalhartTEXAS32000
CaprockNEW-MEXICO21980
SabinosoNEW-MEXICO22021
NinaviewCOLORADO12023
FarleyNEW-MEXICO12025
GrenvilleNEW-MEXICO12025
Cooley LakeNEW-MEXICO11999
RosebudNEW-MEXICO12025
PostTEXAS12012
ChanningTEXAS11999
MiamiTEXAS12000
DoughertyTEXAS12016

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