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Species · Utah · BBS 2026 Release · 1966–2025

Black-headed Grosbeak Population Trend in Utah

All statesForest birds

Black-headed Grosbeak in Utah has surged: up 222% on the route-weighted index since 1970.

+222%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 →
78Routes 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 →
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 Black-headed Grosbeak Trends in UtahNotable 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 Utah: up 222% on the route-weighted index since 1970.

Black-headed Grosbeak Population Forecast in Utah

If the recent trend holds, Black-headed Grosbeak in Utah is projected to rise about 12% by 2030 — from 1.8 in 2025 to a central estimate of 2.0 (95% range 1.2–2.7). A 5-year backtest shows a typical error of ±28.3%, with 80% of held-out values landing inside the 95% band.

+12%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 →
2.0Projected 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 →
1.2–2.795% 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 →
±28.3%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, Black-headed Grosbeak in Utah is projected to rise about 12% by 2030 — from 1.8 in 2025 to a central estimate of 2.0 (95% range 1.2–2.7). A 5-year backtest shows a typical error of ±28.3%, 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 →
20261.91.12.6
20271.91.12.6
20281.91.22.6
20291.91.22.7
20302.01.22.7

Black-headed Grosbeak Survey Routes in Utah

Routes recording Black-headed Grosbeak in Utah.
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 →
Gooseberry1420251994
Main Canyon1120251989
Ant Flat-Ogden Can920251994
La Sal 2920062003
Newcastle920251997
Beck819871971
Fish Lake Nf820251997
Hardware Ranch820231994
Moab820251986
Beaver720251968
Heber Mtn.720251996
Moon Lake 2720232004
Alton620111997
La Sal 3620252007
Uintah Nf519941990
Jensen520252002
Richfield520191994
Beck 2520251990
Kamas520192005
Woodruff520252002
Pine Creek420102010
Aneth320251993
Moquith Mtn320011997
Moon Lake320021995
Hanna320241998

Black-headed Grosbeak Population Trend in Other States

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