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

Savannah Sparrow In Shortgrass Prairie

All regionsShortgrass PrairieGrassland birds

Savannah Sparrow in Shortgrass Prairie has collapsed: down 88% on the route-weighted index since 1980.

-88%Since 1980TrendPercent 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 →
25Routes 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 →
34YearsYears 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 →

Savannah Sparrow has collapsed in Shortgrass Prairie: down 88% on the route-weighted index since 1980.

Forecast

If the recent trend holds, Savannah Sparrow in Shortgrass Prairie is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.26). A 5-year backtest shows a typical error of ±151.7%, 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 →
0.03Projected 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 →
0.00–0.2695% 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 →
±151.7%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, Savannah Sparrow in Shortgrass Prairie is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.26). A 5-year backtest shows a typical error of ±151.7%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.040.000.27
20260.030.000.26
20270.030.000.26
20280.030.000.26
20290.030.000.26

Routes In Shortgrass Prairie

Routes recording Savannah 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 →
AbarrCOLORADO81969
Adams Co.COLORADO52019
Wildhorse LCOLORADO42000
Pine BluffWYOMING31999
GilpinCOLORADO22016
HudsonCOLORADO22000
VillegreenCOLORADO22000
RosebudNEW-MEXICO22003
MaxwellNEW-MEXICO22003
BriggsdaleCOLORADO12024
RushCOLORADO12017
BethuneCOLORADO12023
GroverCOLORADO12011
LimonCOLORADO12015
KirkCOLORADO12022
NeegrandeCOLORADO12003
JulesburgCOLORADO12009
PritchettCOLORADO12016
ElbertCOLORADO12005
DaltonNEBRASKA11977
BereaNEBRASKA11980
FloydNEW-MEXICO12011
SedanNEW-MEXICO11999
YoderWYOMING12024
CheyenneWYOMING12021

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