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Species · South Carolina · BBS 2026 Release · 1966–2025

Blue Grosbeak Population Trend in South Carolina

All statesForest birds

Blue Grosbeak in South Carolina has held roughly steady: down 7% on the route-weighted index since 1968.

-7%Since 1968TrendPercent 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 →
51Routes 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 →
59YearsYears 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 South CarolinaNotable 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 South Carolina. See the full index history below.

Blue Grosbeak Population Forecast in South Carolina

If the recent trend holds, Blue Grosbeak in South Carolina is projected to stay roughly flat through 2030, near 9.7 (95% range 5.3–14). A 5-year backtest shows a typical error of ±21.6%, with 100% of held-out values landing inside the 95% band.

+9%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 →
9.7Projected 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 →
5.3–1495% 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 →
±21.6%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 South Carolina is projected to stay roughly flat through 2030, near 9.7 (95% range 5.3–14). A 5-year backtest shows a typical error of ±21.6%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20269.75.314
20279.75.314
20289.75.314
20299.75.314
20309.75.314

Blue Grosbeak Survey Routes in South Carolina

Routes recording Blue Grosbeak in South Carolina.
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 →
Little Mtn2519881966
New Holland2420251967
Holly Hill2120251972
New Ellenton2120252010
Carvers Bay2120121998
Sandhills1720251995
Ward1620252017
Green Sea1620252019
Boykin Ml Pd1519681966
Coward1420251966
Pendleton1419761966
Greenwood1420251998
Nixville1420251998
Rome1320251967
Landrum1019921972
Pinewood1020191998
Prosperity1020241992
Foreston920251966
Bishopville920251970
Owings920041995
Kingstree920102010
Chesnee920151992
Boiling Spgs819791967
Bennettsville820171998
Dillon720211970

Blue Grosbeak Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamarylandminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniasouth-dakotatennesseetexasutahvirginiawest-virginiawyoming

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