BirdAnalyst
Species · Montana · BBS 2025 Release · 1966–2024

Ring-billed Gull Population Trend in Montana

All statesWetland birds

Ring-billed Gull in Montana has surged: up 11× on the route-weighted index since 1970.

11×Since 1970TrendPercent 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 →
54YearsYears 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 MontanaNotable 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 Montana: up 11× on the route-weighted index since 1970.

Ring-billed Gull Population Forecast in Montana

If the recent trend holds, Ring-billed Gull in Montana is projected to fall about 33% by 2029 — from 8.0 in 2024 to a central estimate of 5.4 (95% range 0.04–11). A 5-year backtest shows a typical error of ±80.9%, with 100% of held-out values landing inside the 95% band.

-33%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 →
5.4Projected 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 →
0.04–1195% 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 →
±80.9%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 Montana is projected to fall about 33% by 2029 — from 8.0 in 2024 to a central estimate of 5.4 (95% range 0.04–11). A 5-year backtest shows a typical error of ±80.9%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20255.10.0010
20265.20.0011
20275.20.0011
20285.30.0011
20295.40.0411

Ring-billed Gull Survey Routes in Montana

Routes recording Ring-billed Gull in Montana.
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 →
Glasgow25420241972
Augusta12820241978
Ester Lake7120242017
Sun River5620242015
Pablo Res.4720241996
Two Dot3220241976
Great Falls1920211972
Whitlash1820242011
Westby1520242015
Shawmut1220241982
Chinook1220242017
Willow Creek 21120142000
Malta1020241975
Harlem920211980
Jordan720241968
Boulder720221975
Highwood620171980
Oswego520211983
Beaverhead520191975
Heart Butte520242016
Roy420131991
Savage419931993
Flatwillow 2420172017
Flatwillow420071976
Virgelle320241990

Ring-billed Gull Population Trend in Other States

alabamaarizonacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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