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

Vesper Sparrow In Shortgrass Prairie

All regionsShortgrass PrairieGrassland birds

Vesper Sparrow in Shortgrass Prairie has surged: up 476% on the route-weighted index since 1970.

+476%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 →
57Routes 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 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 Shortgrass Prairie: up 476% on the route-weighted index since 1970.

Vesper Sparrow In Shortgrass Prairie Population Forecast

If the recent trend holds, Vesper Sparrow in Shortgrass Prairie is projected to rise about 106% by 2030 — from 0.66 in 2025 to a central estimate of 1.4 (95% range 0.66–2.1). A 5-year backtest shows a typical error of ±76.9%, with 80% of held-out values landing inside the 95% band.

+106%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 →
1.4Projected 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 →
0.66–2.195% 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 →
±76.9%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, Vesper Sparrow in Shortgrass Prairie is projected to rise about 106% by 2030 — from 0.66 in 2025 to a central estimate of 1.4 (95% range 0.66–2.1). A 5-year backtest shows a typical error of ±76.9%, with 80% 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 →
20261.30.582.0
20271.30.602.0
20281.30.622.0
20291.30.642.0
20301.40.662.1

Routes In Shortgrass Prairie

Routes recording Vesper 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 →
ElbertCOLORADO172025
ChugwaterWYOMING172024
UlyssesKANSAS162003
ArsenalCOLORADO122015
FarleyNEW-MEXICO92025
KirkCOLORADO82023
KiowaCOLORADO72018
MaxwellNEW-MEXICO72025
BennettCOLORADO62018
CheyenneWYOMING62025
KimballNEBRASKA52025
MarslandNEBRASKA52021
FloydNEW-MEXICO52021
RuletonKANSAS42010
Two ButtesCOLORADO32012
Kiowa 2COLORADO32025
BenkelmanNEBRASKA32007
CrawfordNEBRASKA32019
LamesaTEXAS31976
Pine BluffWYOMING32023
Adams Co.COLORADO22022
Gordon CreekCOLORADO22024
VillegreenCOLORADO21999
Cone MtnCOLORADO22019
NunnCOLORADO22019

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