BirdAnalyst
Species · BCR 18 · BBS 2025 Release · 1966–2024

Rufous-crowned Sparrow In Shortgrass Prairie

All regionsShortgrass PrairieGeneralists

Rufous-crowned Sparrow in Shortgrass Prairie has collapsed: down 82% on the route-weighted index since 1970.

-82%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 →
54YearsYears 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 82% 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 2029, near 0.08 (95% range 0.00–0.22). A 5-year backtest shows a typical error of ±255.5%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.08Projected 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 →
0.00–0.2295% 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 →
±255.5%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 2029, near 0.08 (95% range 0.00–0.22). A 5-year backtest shows a typical error of ±255.5%, 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 →
20250.080.000.23
20260.080.000.23
20270.080.000.22
20280.080.000.22
20290.080.000.22

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
GrenvilleNEW-MEXICO32024
VariaderoNEW-MEXICO32022
DalhartTEXAS32000
CaprockNEW-MEXICO21980
SabinosoNEW-MEXICO22021
NinaviewCOLORADO12023
FarleyNEW-MEXICO12017
Cooley LakeNEW-MEXICO11999
RosebudNEW-MEXICO12024
PostTEXAS12012
ChanningTEXAS11999
MiamiTEXAS12000
DoughertyTEXAS12016

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