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Species · Wisconsin · BBS 2026 Release · 1966–2025

Ring-billed Gull Population Trend in Wisconsin

All statesWetland birds

Ring-billed Gull in Wisconsin has held roughly steady: down 6% on the route-weighted index since 1969.

-6%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 →
49Routes 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 Ring-billed Gull Trends in WisconsinNotable 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 Wisconsin. See the full index history below.

Ring-billed Gull Population Forecast in Wisconsin

If the recent trend holds, Ring-billed Gull in Wisconsin is projected to rise about 186% by 2030 — from 2.4 in 2025 to a central estimate of 6.8 (95% range 0.00–17). A 5-year backtest shows a typical error of ±685.4%, with 100% of held-out values landing inside the 95% band.

+186%Change by 2030TrendPercent 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 →
6.8Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1795% 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 →
±685.4%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, Ring-billed Gull in Wisconsin is projected to rise about 186% by 2030 — from 2.4 in 2025 to a central estimate of 6.8 (95% range 0.00–17). A 5-year backtest shows a typical error of ±685.4%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20266.70.0017
20276.70.0017
20286.70.0017
20296.80.0017
20306.80.0017

Ring-billed Gull Survey Routes in Wisconsin

Routes recording Ring-billed Gull in Wisconsin.
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 →
Omro9620011979
Kiel8020251998
Omro 26320252002
Wis Rapids3420231989
Holland2320251998
Cumberland2020051989
Brownsville1820102010
Couderay1620121993
Washington I1420251967
Crandon1320152005
Dresser819931987
Chaffey720161975
Rib Lake620122012
Iron River420251986
Shanagolden319961996
Esdaile320032003
Stratford320132013
Manitowoc320231981
Amnicon Falls320231998
Conover320192019
Buena Vista320142014
Minong220031987
Grand View220002000
Phillips220152014
Verona220252004

Ring-billed Gull Population Trend in Other States

alabamaarizonacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwest-virginiawyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.