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

Savannah Sparrow Population Trend in South Dakota

All statesGrassland birds

Savannah Sparrow in South Dakota has edged down: down 21% on the route-weighted index since 1969.

-21%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 →
37Routes 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 Savannah 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 Savannah Sparrow in South Dakota. See the full index history below.

Savannah Sparrow Population Forecast in South Dakota

If the recent trend holds, Savannah Sparrow in South Dakota is projected to rise about 71% by 2029 — from 1.4 in 2024 to a central estimate of 2.3 (95% range 0.85–3.8). A 5-year backtest shows a typical error of ±92.6%, with 80% of held-out values landing inside the 95% band.

+71%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 →
2.3Projected 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 →
0.85–3.895% 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 →
±92.6%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, Savannah Sparrow in South Dakota is projected to rise about 71% by 2029 — from 1.4 in 2024 to a central estimate of 2.3 (95% range 0.85–3.8). A 5-year backtest shows a typical error of ±92.6%, with 80% 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 →
20252.20.713.7
20262.20.743.7
20272.30.783.8
20282.30.813.8
20292.30.853.8

Savannah Sparrow Survey Routes in South Dakota

Routes recording Savannah 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 →
Forbes1620241967
White Lake1420111969
Eagle Butte1420152011
Isabel1120152009
Veblen1020231967
Gorman1020101980
Lane819991977
Britton820231972
Gettysburg820231969
Long Lake720191967
Laplant620092009
Volunteer620122011
Roswell520121968
Broadland520171999
Turton520242010
Volga420241968
Howard220241976
Rosebud220092009
Raymond220211967
Crow Creek220231967
Harding220141999
Lane 2220142000
Lennox120241971
Tripp120221988
Chamberlain120051967

Savannah Sparrow Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandtennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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