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

Great Horned Owl Population Trend in South Dakota

All statesGeneralists

Great Horned Owl in South Dakota has collapsed: down 85% on the route-weighted index since 1969.

-85%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 →
57Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Great Horned Owl 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 →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Great Horned Owl has collapsed in South Dakota: down 85% on the route-weighted index since 1969.

Great Horned Owl Population Forecast in South Dakota

If the recent trend holds, Great Horned Owl in South Dakota is projected to fall about 23% by 2028 — from 0.10 in 2023 to a central estimate of 0.08 (95% range 0.00–0.54). A 5-year backtest shows a typical error of ±27.4%, with 100% of held-out values landing inside the 95% band.

-23%Change by 2028TrendPercent 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 →
0.08Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.5495% 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 →
±27.4%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, Great Horned Owl in South Dakota is projected to fall about 23% by 2028 — from 0.10 in 2023 to a central estimate of 0.08 (95% range 0.00–0.54). A 5-year backtest shows a typical error of ±27.4%, with 100% of held-out values landing inside the 95% band.19672028
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 →
20240.110.000.57
20250.100.000.56
20260.090.000.56
20270.080.000.55
20280.080.000.54

Great Horned Owl Survey Routes in South Dakota

Routes recording Great Horned Owl 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 →
Geddes420211967
Howard220221970
Roswell220141968
Lane219991967
Ft Thompson220111973
Veblen219891967
Conde219831983
Badlands219831983
Lacreek220191996
Lennox120181969
Tripp120221976
White Lake119921972
Chamberlain120061968
Winner120231968
Rosebud119731967
Rockyford120232023
Volga120211968
Raymond120171984
Broadland120101977
Crow Creek119721968
Wilmot120141969
Britton120161967
Forbes120231977
Gettysburg120211996
Long Lake120191986

Great Horned Owl 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.