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Species · Kansas · BBS 2026 Release · 1966–2025

Black-headed Grosbeak Population Trend in Kansas

All statesForest birds

Black-headed Grosbeak in Kansas has declined: down 37% on the route-weighted index since 1972.

-37%Since 1972TrendPercent 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 →
14Routes 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 →
43YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-headed Grosbeak 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 →

No notable trend signals for Black-headed Grosbeak in Kansas. See the full index history below.

Black-headed Grosbeak Population Forecast in Kansas

If the recent trend holds, Black-headed Grosbeak in Kansas is projected to fall about 86% by 2030 — from 0.11 in 2025 to a central estimate of 0.01 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±48.2%, with 100% of held-out values landing inside the 95% band.

-86%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 →
0.01Projected 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 →
0.00–0.1495% 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 →
±48.2%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, Black-headed Grosbeak in Kansas is projected to fall about 86% by 2030 — from 0.11 in 2025 to a central estimate of 0.01 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±48.2%, 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 →
20260.020.000.15
20270.020.000.15
20280.020.000.15
20290.020.000.14
20300.010.000.14

Black-headed Grosbeak Survey Routes in Kansas

Routes recording Black-headed Grosbeak 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 →
Phillipsburg320251968
Logan219791977
St John219891969
Albert220081982
Minneapolis220092009
Covert120141968
Gove119901988
Missler119801980
Rexford120232011
Coats119841972
Coldwater119741974
Gray119981982
Hays119771977
Leoville120181976

Black-headed Grosbeak Population Trend in Other States

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