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

Ring-billed Gull Population Trend in South Dakota

All statesWetland birds

Ring-billed Gull in South Dakota has edged up: up 19% on the route-weighted index since 1969.

+19%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 →
28Routes 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 →
53YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Ring-billed Gull 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 Ring-billed Gull in South Dakota. See the full index history below.

Ring-billed Gull Population Forecast in South Dakota

If the recent trend holds, Ring-billed Gull in South Dakota is projected to rise about 71% by 2029 — from 0.95 in 2024 to a central estimate of 1.6 (95% range 0.07–3.2). A 5-year backtest shows a typical error of ±39.6%, 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 →
1.6Projected 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 →
0.07–3.295% 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 →
±39.6%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, Ring-billed Gull in South Dakota is projected to rise about 71% by 2029 — from 0.95 in 2024 to a central estimate of 1.6 (95% range 0.07–3.2). A 5-year backtest shows a typical error of ±39.6%, 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 →
20251.60.003.1
20261.60.013.1
20271.60.033.2
20281.60.053.2
20291.60.073.2

Ring-billed Gull Survey Routes in South Dakota

Routes recording Ring-billed Gull 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 →
Britton2920231970
Laplant1419901990
Wilmot1120241967
Raymond920211968
Lennox820042004
Forbes720241979
Volga620211972
Roswell620092007
Lacreek519961996
Veblen420081978
Hayes419951995
Long Lake320191977
Tripp220072007
Pioneer220242024
Chamberlain220112011
Ft Thompson220112011
Howard120121980
White Lake119731973
Cottonwood119921992
Broadland120122010
Gettysburg120232016
Volunteer120092009
Ottumwa119921992
Harding120042004
Fort Pierre120241968

Ring-billed Gull Population Trend in Other States

alabamaarizonacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinatexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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