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

Ring-billed Gull Population Trend in North Dakota

All statesWetland birds

Ring-billed Gull in North Dakota has surged: up 855% on the route-weighted index since 1969.

+855%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 →
42Routes 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 North 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 increasecomputed 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 →

Ring-billed Gull has surged in North Dakota: up 855% on the route-weighted index since 1969.

Ring-billed Gull Population Forecast in North Dakota

If the recent trend holds, Ring-billed Gull in North Dakota is projected to fall about 29% by 2029 — from 28 in 2024 to a central estimate of 20 (95% range 12–29). A 5-year backtest shows a typical error of ±27.2%, with 60% of held-out values landing inside the 95% band.

-29%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 →
20Projected 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 →
12–2995% 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 →
±27.2%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 North Dakota is projected to fall about 29% by 2029 — from 28 in 2024 to a central estimate of 20 (95% range 12–29). A 5-year backtest shows a typical error of ±27.2%, with 60% 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 →
2025191028
2026191128
2027201128
2028201128
2029201229

Ring-billed Gull Survey Routes in North Dakota

Routes recording Ring-billed Gull in North 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 →
Wild Rose29520241982
Lakota 29220242010
Edgeley7220241994
Niles6820241989
Horsehead Lk6220241980
Danzig5920141991
Douglas Crk4420241982
Carpio4120231969
Webster2320241995
Danzig 22120242019
Braddock2020221988
Lake George1820221967
Buchanan1820241967
Wimbledon1720241981
Parshall1720131982
Montpelier1620241993
Lakota1320091968
Stanley1220241977
Sheyenne Lk920241980
Bowesmont720132011
Rolla720241976
Kempton620001967
Powers Lake620241982
Bowman420101970
Forman320231971

Ring-billed Gull Population Trend in Other States

alabamaarizonacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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