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

Red-winged Blackbird Population Trend in South Dakota

All statesGeneralists

Red-winged Blackbird in South Dakota has declined: down 25% on the route-weighted index since 1969.

-25%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 Red-winged Blackbird 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 Red-winged Blackbird in South Dakota. See the full index history below.

Red-winged Blackbird Population Forecast in South Dakota

If the recent trend holds, Red-winged Blackbird in South Dakota is projected to fall about 26% by 2029 — from 100 in 2024 to a central estimate of 74 (95% range 37–111). A 5-year backtest shows a typical error of ±35.3%, with 20% of held-out values landing inside the 95% band.

-26%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 →
74Projected 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 →
37–11195% 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 →
±35.3%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, Red-winged Blackbird in South Dakota is projected to fall about 26% by 2029 — from 100 in 2024 to a central estimate of 74 (95% range 37–111). A 5-year backtest shows a typical error of ±35.3%, with 20% 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 →
20257640113
20267639112
20277538112
20287438111
20297437111

Red-winged Blackbird Survey Routes in South Dakota

Routes recording Red-winged Blackbird 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 →
Forbes51220241967
Turton50320241985
Roswell32320141967
Broadland28920171967
Lacreek27020231991
Cedar Pass23520231967
Conde21619841967
Lodgepole19920241990
Long Lake18220191967
White Lake18120111967
Geddes16420231967
Isabel15920151990
Rockyford14420231967
Eagle Butte14020151990
Gettysburg13520231969
Wilmot13220241967
Raymond13020211967
Lane 212720142000
Howard12620241970
Promise12420151971
Crow Creek12120231967
Hayes11820241989
Ottumwa11520221967
Volga11320241967
Volunteer10220191967

Red-winged Blackbird 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.