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

Brown Thrasher Population Trend in South Carolina

All statesForest birds

Brown Thrasher in South Carolina has declined: down 47% on the route-weighted index since 1968.

-47%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 Brown Thrasher 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 Brown Thrasher in South Carolina. See the full index history below.

Brown Thrasher Population Forecast in South Carolina

If the recent trend holds, Brown Thrasher in South Carolina is projected to rise about 12% by 2030 — from 5.3 in 2025 to a central estimate of 5.9 (95% range 3.2–8.6). A 5-year backtest shows a typical error of ±26.3%, with 100% of held-out values landing inside the 95% band.

+12%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 →
5.9Projected 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 →
3.2–8.695% 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 →
±26.3%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, Brown Thrasher in South Carolina is projected to rise about 12% by 2030 — from 5.3 in 2025 to a central estimate of 5.9 (95% range 3.2–8.6). A 5-year backtest shows a typical error of ±26.3%, 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 →
20266.03.38.6
20276.03.38.6
20285.93.38.6
20295.93.28.6
20305.93.28.6

Brown Thrasher Survey Routes in South Carolina

Routes recording Brown Thrasher 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 →
Owings2120041992
Nixville1820251998
Chesnee1620151992
Red Bluff1520251996
New Holland1120251967
Boykin Ml Pd1019681966
Salem Xrd1020191982
Boiling Spgs1019791967
Owings 21020252005
Coward920251966
Bishopville820251970
Landrum819921972
Sandhills820251994
Blacksburg820131999
Pinewood720191998
Hardeeville620251967
Pendleton619761966
Barton Creek620221967
New Ellenton620252010
Johns Isle519791966
Rome520251967
Holly Hill520251972
Little Mtn519881966
Ward520252017
Green Sea520252010

Brown Thrasher Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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