BirdAnalyst
Species · South Dakota · BBS 2026 Release · 1966–2025

Bobolink Population Trend in South Dakota

All statesGrassland birds

Bobolink in South Dakota has increased: up 41% on the route-weighted index since 1969.

+41%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 →
56Routes 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 Bobolink 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 Bobolink in South Dakota. See the full index history below.

Bobolink Population Forecast in South Dakota

If the recent trend holds, Bobolink in South Dakota is projected to rise about 18% by 2030 — from 5.4 in 2025 to a central estimate of 6.4 (95% range 3.4–9.4). A 5-year backtest shows a typical error of ±38.6%, with 100% of held-out values landing inside the 95% band.

+18%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 →
6.4Projected 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 →
3.4–9.495% 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 →
±38.6%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, Bobolink in South Dakota is projected to rise about 18% by 2030 — from 5.4 in 2025 to a central estimate of 6.4 (95% range 3.4–9.4). A 5-year backtest shows a typical error of ±38.6%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20266.23.19.2
20276.23.29.3
20286.33.39.3
20296.33.39.4
20306.43.49.4

Bobolink Survey Routes in South Dakota

Routes recording Bobolink 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 →
Promise3620151971
Lodgepole3320251990
Eagle Butte2620151999
Lane 22520142000
Veblen2220231967
Lacreek2120251991
Gettysburg2020231969
Roswell1720141967
Isabel1720152013
White Lake1620111967
Volga1620251967
Lane1619991967
Gorman1620101979
Crow Creek1520231967
Wilmot1420251967
Forbes1420251967
Conde1419841967
Long Lake1320191967
Turton1220251985
Chamberlain1120111967
Englewood1120211992
Howard1020251970
Tripp820251971
Raymond820211967
Laplant820151971

Bobolink Population Trend in Other States

californiacoloradoconnecticutidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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