BirdAnalyst
Species · South Carolina · BBS 2025 Release · 1966–2024

Blue Grosbeak Population Trend in South Carolina

All statesGeneralists

Blue Grosbeak in South Carolina has held roughly steady: down 4% on the route-weighted index since 1968.

-4%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 →
58YearsYears 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 rise about 21% by 2029 — from 8.0 in 2024 to a central estimate of 9.7 (95% range 5.3–14). A 5-year backtest shows a typical error of ±32.9%, with 100% of held-out values landing inside the 95% band.

+21%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 →
9.7Projected 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 →
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 →
±32.9%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 rise about 21% by 2029 — from 8.0 in 2024 to a central estimate of 9.7 (95% range 5.3–14). A 5-year backtest shows a typical error of ±32.9%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20259.75.314
20269.75.314
20279.75.314
20289.75.314
20299.75.314

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
Green Sea2320242019
Carvers Bay2120121998
New Holland2020241967
Lowrys2020212017
Joanna2020231999
Foreston1720211966
Boykin Ml Pd1519681966
Pendleton1419761966
Nixville1420211998
Rome1320241967
Ward1220212017
Sandhills1220241995
Holly Hill1120241972
Bishopville1120241970
Wagener1020241966
Landrum1019921972
Pinewood1020191998
Prosperity1020241992
Owings920041995
Kingstree920102010
Owings 2920242005
Chesnee920151992
Boiling Spgs819791967
Ridgeway820212010

Blue Grosbeak Population Trend in Other States

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

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