BirdAnalyst
Species · Utah · BBS 2025 Release · 1966–2024

Blue Grosbeak Population Trend in Utah

All statesGeneralists

Blue Grosbeak in Utah has increased: up 26% on the route-weighted index since 1979.

+26%Since 1979TrendPercent 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 →
40Routes 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 →
47YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blue 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 →

No notable trend signals for Blue Grosbeak in Utah. See the full index history below.

Blue Grosbeak Population Forecast in Utah

If the recent trend holds, Blue Grosbeak in Utah is projected to fall about 57% by 2029 — from 0.54 in 2024 to a central estimate of 0.23 (95% range 0.00–0.95). A 5-year backtest shows a typical error of ±53%, with 100% of held-out values landing inside the 95% band.

-57%Change by 2029TrendPercent 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 →
0.23Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.9595% 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 →
±53%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, Blue Grosbeak in Utah is projected to fall about 57% by 2029 — from 0.54 in 2024 to a central estimate of 0.23 (95% range 0.00–0.95). A 5-year backtest shows a typical error of ±53%, with 100% of held-out values landing inside the 95% band.19722029
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 →
20250.270.000.98
20260.260.000.98
20270.250.000.97
20280.240.000.96
20290.230.000.95

Blue Grosbeak Survey Routes in Utah

Routes recording Blue 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 →
Aneth1220241986
Castleton519851977
Oak City420241972
Moquith Mtn420242005
Goshen320241982
Bullfrog Bay320082008
Book Ridge220222019
Iron Springs220011988
Vernal220072003
Westwater220241997
Moab220241986
Jensen220241999
Wellington 3120232012
Timpie Spg119831979
Arches Np119921992
Dragerton120102009
Beaver120001986
Canyonlands119941994
Hanksville120182001
Boulder120031986
Hite120132013
Wellington 2120112005
Moon Lake120022002
Castle Dale120242024
Gooseberry119941994

Blue Grosbeak Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamarylandminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniasouth-carolinasouth-dakotatennesseetexasvirginiawest-virginiawyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.