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

Barn Swallow Population Trend in South Dakota

All statesAerial insectivores

Barn Swallow in South Dakota has held roughly steady: down 2% on the route-weighted index since 1969.

-2%Since 1969TrendPercent 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 →
65Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Barn Swallow Trends in South DakotaNotable 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 Barn Swallow in South Dakota. See the full index history below.

Barn Swallow Population Forecast in South Dakota

If the recent trend holds, Barn Swallow in South Dakota is projected to rise about 29% by 2029 — from 10 in 2024 to a central estimate of 13 (95% range 0.00–27). A 5-year backtest shows a typical error of ±25.1%, with 100% of held-out values landing inside the 95% band.

+29%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 →
13Projected 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 →
0.00–2795% 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 →
±25.1%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, Barn Swallow in South Dakota is projected to rise about 29% by 2029 — from 10 in 2024 to a central estimate of 13 (95% range 0.00–27). A 5-year backtest shows a typical error of ±25.1%, with 100% of held-out values landing inside the 95% band.19672029
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 →
2025140.1027
2026140.0027
2027130.0027
2028130.0027
2029130.0027

Barn Swallow Survey Routes in South Dakota

Routes recording Barn Swallow in South Dakota.
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 →
Isabel13420151990
Promise12720151971
Eagle Butte11820151990
Conde9819841967
Lane 26420142000
Volga6220241967
Cedar Pass5420231967
Lane5319991967
Chamberlain3520111967
Laplant3520151971
White Lake3120111967
Roswell3120141967
Geddes3020231967
Tripp2620241967
Rockyford2520231967
Howard2420241970
Ft Thompson2420111967
Lacreek2420231991
Forbes2020241967
Owanka2020221967
Long Lake1920191967
Britton1820231967
Crow Creek1520231967
Harding1520191968
Badlands1520231982

Barn Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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