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

Warbling Vireo In Shortgrass Prairie

All regionsShortgrass PrairieForest birds

Warbling Vireo in Shortgrass Prairie has surged: up 94% on the route-weighted index since 1973.

+94%Since 1973TrendPercent 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 →
41Routes 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 →
52YearsYears 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 →

Warbling Vireo has surged in Shortgrass Prairie: up 94% on the route-weighted index since 1973.

Warbling Vireo In Shortgrass Prairie Population Forecast

If the recent trend holds, Warbling Vireo in Shortgrass Prairie is projected to stay roughly flat through 2030, near 0.16 (95% range 0.03–0.29). A 5-year backtest shows a typical error of ±56.3%, with 100% of held-out values landing inside the 95% band.

+3%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 →
0.16Projected 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 →
0.03–0.2995% 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 →
±56.3%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, Warbling Vireo in Shortgrass Prairie is projected to stay roughly flat through 2030, near 0.16 (95% range 0.03–0.29). A 5-year backtest shows a typical error of ±56.3%, 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 →
20260.150.030.28
20270.150.030.28
20280.160.030.28
20290.160.030.28
20300.160.030.29

Routes In Shortgrass Prairie

Routes recording Warbling Vireo 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 →
Fort MorganCOLORADO32025
DaltonNEBRASKA32025
KiowaCOLORADO21998
Wildhorse LCOLORADO22022
JulesburgCOLORADO22021
Arsenal 2COLORADO22025
WallaceKANSAS21999
Murray LakeNEBRASKA22025
CrawfordNEBRASKA22019
Pine RidgeNEBRASKA22023
YoderWYOMING22024
PinneoCOLORADO12014
FlemingCOLORADO12006
Last ChanceCOLORADO12001
BoyeroCOLORADO11992
LamarCOLORADO12010
HudsonCOLORADO12016
Adams Co.COLORADO12015
CrowleyCOLORADO12007
VillegreenCOLORADO12000
AmherstCOLORADO11995
NeegrandeCOLORADO12007
ElbertCOLORADO12025
Doyle Bridge 2COLORADO12023
ArsenalCOLORADO12015

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