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

Blue-headed Vireo Population Trend in South Carolina

All statesForest birds

Blue-headed Vireo in South Carolina has surged: up 428% on the route-weighted index since 1987.

+428%Since 1987TrendPercent 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 →
15Routes 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 →
35YearsYears 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-headed Vireo 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 →

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 →

Blue-headed Vireo has surged in South Carolina: up 428% on the route-weighted index since 1987.

Blue-headed Vireo Population Forecast in South Carolina

If the recent trend holds, Blue-headed Vireo in South Carolina is projected to fall about 43% by 2029 — from 0.57 in 2024 to a central estimate of 0.33 (95% range 0.01–0.64). A 5-year backtest shows a typical error of ±74%, with 100% of held-out values landing inside the 95% band.

-43%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 →
0.33Projected 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 →
0.01–0.6495% 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 →
±74%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-headed Vireo in South Carolina is projected to fall about 43% by 2029 — from 0.57 in 2024 to a central estimate of 0.33 (95% range 0.01–0.64). A 5-year backtest shows a typical error of ±74%, with 100% of held-out values landing inside the 95% band.19772029
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 →
20250.310.000.63
20260.310.000.63
20270.320.000.63
20280.320.010.64
20290.330.010.64

Blue-headed Vireo Survey Routes in South Carolina

Routes recording Blue-headed Vireo 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 →
Battlecreek720241999
Whitmire420242010
Salem Xrd220071990
Blacksburg219991999
Campobello220112010
Rome119881988
Sandhills120142014
Cauthens Xrd120171995
Owings119961996
Barton Creek120011986
Landrum119881987
Plum Branch120231977
Joanna120221999
Prosperity120041997
Salem120242014

Blue-headed Vireo Population Trend in Other States

alabamaconnecticutgeorgiakentuckymainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandtennesseevermontvirginiawest-virginiawisconsin

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