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Species · Kansas · BBS 2026 Release · 1966–2025

Bell's Vireo Population Trend in Kansas

All statesForest birds

Bell's Vireo in Kansas has surged: up 206% on the route-weighted index since 1969.

+206%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 →
58Routes In StateSurvey 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 Bell's Vireo Trends in KansasNotable 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 →

Bell's Vireo has surged in Kansas: up 205% on the route-weighted index since 1969.

Bell's Vireo Population Forecast in Kansas

If the recent trend holds, Bell's Vireo in Kansas is projected to stay roughly flat through 2030, near 2.2 (95% range 1.5–2.9). A 5-year backtest shows a typical error of ±26%, with 40% of held-out values landing inside the 95% band.

-6%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 →
2.2Projected 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 →
1.5–2.995% 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 →
±26%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, Bell's Vireo in Kansas is projected to stay roughly flat through 2030, near 2.2 (95% range 1.5–2.9). A 5-year backtest shows a typical error of ±26%, with 40% 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 →
20262.11.42.8
20272.11.42.8
20282.11.52.8
20292.21.52.8
20302.21.52.9

Bell's Vireo Survey Routes in Kansas

Routes recording Bell's Vireo in Kansas.
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 →
Kanopolis1320251970
Lincolnville1120242002
Trading Post920252000
Barclay720251967
Thrall519671967
St John520191968
Ellinor520251972
Minneapolis520191967
Jamestown520242000
Dover420221968
Wreford420241967
Hanover420251969
Morehead420252001
Severance420252000
Humboldt320221984
Albert320241968
Hollenberg320251969
Reece320252000
Susank320222016
Solomon320251982
Melrose220181967
Jewell 2220242009
Olathe220211968
Chapman219811968
Buckeye220231967

Bell's Vireo Population Trend in Other States

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