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

Field Sparrow Population Trend in South Carolina

All statesGeneralists

Field Sparrow in South Carolina has collapsed: down 90% on the route-weighted index since 1968.

-90%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 →
45Routes 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 Field Sparrow 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 declinecomputed 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 →

Field Sparrow has collapsed in South Carolina: down 90% on the route-weighted index since 1968.

Field Sparrow Population Forecast in South Carolina

If the recent trend holds, Field Sparrow in South Carolina is projected to fall about 20% by 2029 — from 1.1 in 2024 to a central estimate of 0.87 (95% range 0.00–4.9). A 5-year backtest shows a typical error of ±80%, with 100% of held-out values landing inside the 95% band.

-20%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 →
0.87Projected 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 →
0.00–4.995% 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 →
±80%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, Field Sparrow in South Carolina is projected to fall about 20% by 2029 — from 1.1 in 2024 to a central estimate of 0.87 (95% range 0.00–4.9). A 5-year backtest shows a typical error of ±80%, 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 →
20251.60.005.6
20261.40.005.5
20271.20.005.3
20281.10.005.1
20290.870.004.9

Field Sparrow Survey Routes in South Carolina

Routes recording Field Sparrow 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 →
Pendleton2919761966
Owings2620041992
Chesnee1620151992
Boiling Spgs1419791967
Boykin Ml Pd1119681966
Campobello920242010
Joanna820231999
Landrum619921972
Anderson520181977
Lowrys420172017
Salem420242010
Blacksburg420131998
Hardeeville319691967
Coward320241966
Little Mtn319881966
Ward320212017
Battlecreek320241999
Cauthens Xrd320211982
Johns Isle219681967
Jamestown219681967
Foreston220211966
Kingstree220102010
Greenwood220191998
Mount Pisgah220211998
Bennettsville220171998

Field Sparrow Population Trend in Other States

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

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