BirdAnalyst
Species · BCR 17 · BBS 2026 Release · 1966–2025

Vesper Sparrow In Badlands and Prairies

All regionsBadlands and PrairiesGrassland birds

Vesper Sparrow in Badlands and Prairies has surged: up 145% on the route-weighted index since 1969.

+145%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 →
137Routes 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 →
58YearsYears 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 →

Vesper Sparrow has surged in Badlands and Prairies: up 145% on the route-weighted index since 1969.

Vesper Sparrow In Badlands and Prairies Population Forecast

If the recent trend holds, Vesper Sparrow in Badlands and Prairies is projected to stay roughly flat through 2030, near 19 (95% range 11–26). A 5-year backtest shows a typical error of ±5.6%, with 100% of held-out values landing inside the 95% band.

+1%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 →
19Projected 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 →
11–2695% 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 →
±5.6%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, Vesper Sparrow in Badlands and Prairies is projected to stay roughly flat through 2030, near 19 (95% range 11–26). A 5-year backtest shows a typical error of ±5.6%, with 100% 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 →
2026181125
2027181125
2028181126
2029181126
2030191126

Routes In Badlands and Prairies

Routes recording Vesper Sparrow in Badlands and Prairies.
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 →
LeroyMONTANA1572025
Custer 2MONTANA1222025
ShawmutMONTANA1032025
CusterMONTANA992022
RoundupMONTANA722025
BrusettMONTANA662024
Wheat BasinMONTANA662025
Eagle ButteSOUTH-DAKOTA622015
DickinsonNORTH-DAKOTA522025
RozetWYOMING492025
WinnettMONTANA462025
SavageMONTANA452025
IsabelSOUTH-DAKOTA412015
Flatwillow 2MONTANA402023
GorhamNORTH-DAKOTA402025
Two DotMONTANA392025
Dunn CenterNORTH-DAKOTA392025
BucknumWYOMING382024
FlatwillowMONTANA362008
PromiseSOUTH-DAKOTA362015
Chuffey SpringMONTANA352025
SeelyWYOMING352000
LindsayMONTANA342024
Hehn DrawMONTANA332025
TobaccoNORTH-DAKOTA312019

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