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Species · Wyoming · BBS 2026 Release · 1966–2025

Black-headed Grosbeak Population Trend in Wyoming

All statesForest birds

Black-headed Grosbeak in Wyoming has surged: up 158% on the route-weighted index since 1970.

+158%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 →
69Routes 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 →
57YearsYears 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 WyomingNotable 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 →

Black-headed Grosbeak has surged in Wyoming: up 158% on the route-weighted index since 1970.

Black-headed Grosbeak Population Forecast in Wyoming

If the recent trend holds, Black-headed Grosbeak in Wyoming is projected to fall about 18% by 2030 — from 0.96 in 2025 to a central estimate of 0.79 (95% range 0.25–1.3). A 5-year backtest shows a typical error of ±17.8%, with 100% of held-out values landing inside the 95% band.

-18%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 →
0.79Projected 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 →
0.25–1.395% 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 →
±17.8%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 Wyoming is projected to fall about 18% by 2030 — from 0.96 in 2025 to a central estimate of 0.79 (95% range 0.25–1.3). A 5-year backtest shows a typical error of ±17.8%, 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 →
20260.770.241.3
20270.770.241.3
20280.780.251.3
20290.780.251.3
20300.790.251.3

Black-headed Grosbeak Survey Routes in Wyoming

Routes recording Black-headed Grosbeak in Wyoming.
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 →
Wilson1520251979
Moskee 31420252022
Wyarno820251974
Sundance720251975
Bald Mtn720071999
Ryan Park719931993
Moose620251978
Buckskin Mtn520251992
Meadowdale520251991
Moskee 2520212002
Fontenelle420251982
Dayton420251980
Crazy Woman420241995
Moskee420011980
Dubois320251973
Brookhurst320161968
Alpine320251979
Walcott320001985
Midvale220222022
Redbird219881968
Savery219951989
Riverside220191998
Clark220251991
Schoonover219901990
Arvada220241986

Black-headed Grosbeak Population Trend in Other States

alaskaarizonacaliforniacoloradoidahokansasmontananebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashington

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