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

Black-and-white Warbler Population Trend in South Carolina

All statesForest birds

Black-and-white Warbler in South Carolina has surged: up 685% on the route-weighted index since 1968.

+685%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 →
25Routes 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 →
55YearsYears 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-and-white Warbler 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 →

Black-and-white Warbler has surged in South Carolina: up 685% on the route-weighted index since 1968.

Black-and-white Warbler Population Forecast in South Carolina

If the recent trend holds, Black-and-white Warbler in South Carolina is projected to fall about 22% by 2030 — from 0.86 in 2025 to a central estimate of 0.67 (95% range 0.22–1.1). A 5-year backtest shows a typical error of ±28.7%, with 100% of held-out values landing inside the 95% band.

-22%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 →
0.67Projected 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 →
0.22–1.195% 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 →
±28.7%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-and-white Warbler in South Carolina is projected to fall about 22% by 2030 — from 0.86 in 2025 to a central estimate of 0.67 (95% range 0.22–1.1). A 5-year backtest shows a typical error of ±28.7%, 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 →
20260.630.191.1
20270.640.191.1
20280.650.201.1
20290.660.211.1
20300.670.221.1

Black-and-white Warbler Survey Routes in South Carolina

Routes recording Black-and-white Warbler 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 →
Plum Branch720251977
Whitmire620242010
Hardeeville419721972
Greenwood420251998
Little Mtn319831966
Lowrys320252017
Battlecreek320252000
Salem Xrd220191983
Ridgeway220252010
Mount Pisgah220251998
Sandhills120242022
Coward119701970
New Holland120251975
Wagener119961987
Bishopville120242024
Landrum119741974
New Ellenton120222022
Campobello120242024
Blacksburg120122012
Joanna120252000
Bennettsville120142000
Olar120082008
Cauthens Xrd120211982
Prosperity120241992
Owings 2120252025

Black-and-white Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawaregeorgiaillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandtennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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