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

Field Sparrow Population Trend in South Dakota

All statesGeneralists

Field Sparrow in South Dakota has declined: down 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 →
40Routes 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 Field Sparrow 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 Field Sparrow in South Dakota. See the full index history below.

Field Sparrow Population Forecast in South Dakota

If the recent trend holds, Field Sparrow in South Dakota is projected to rise about 106% by 2029 — from 0.27 in 2024 to a central estimate of 0.56 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±93.3%, with 100% of held-out values landing inside the 95% band.

+106%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 →
0.56Projected 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 →
0.00–1.795% 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 →
±93.3%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, Field Sparrow in South Dakota is projected to rise about 106% by 2029 — from 0.27 in 2024 to a central estimate of 0.56 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±93.3%, 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 →
20250.580.001.7
20260.580.001.7
20270.570.001.7
20280.570.001.7
20290.560.001.7

Field Sparrow Survey Routes in South Dakota

Routes recording Field Sparrow 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 →
Promise4720151971
Eagle Butte1820151990
Isabel1020151990
Chamberlain920111968
Ft Thompson720111976
Marcus720142014
Raymond619891989
Crow Creek619901968
Railroad Butte520222022
Badlands520231982
White River520141994
Geddes420231971
Rosebud420111967
Fort Pierre419991968
Lane 2320142000
White Lake219811981
Winner220231988
Roswell220121994
Lane219991985
Veblen219951970
Wind Cave Np220242004
Reva220241979
Pleasant Val220222022
Turton220232009
Lennox120241999

Field Sparrow Population Trend in Other States

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

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