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

Franklin's Gull Population Trend in North Dakota

All statesWetland birds

Franklin's Gull in North Dakota has surged: up 452% on the route-weighted index since 1970.

+452%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 →
39Routes 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 Franklin's 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 →

Franklin's Gull has surged in North Dakota: up 452% on the route-weighted index since 1970.

Franklin's Gull Population Forecast in North Dakota

If the recent trend holds, Franklin's Gull in North Dakota is projected to fall about 66% by 2029 — from 41 in 2024 to a central estimate of 14 (95% range 0.00–29). A 5-year backtest shows a typical error of ±293.1%, with 80% of held-out values landing inside the 95% band.

-66%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 →
14Projected 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 →
0.00–2995% 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 →
±293.1%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, Franklin's Gull in North Dakota is projected to fall about 66% by 2029 — from 41 in 2024 to a central estimate of 14 (95% range 0.00–29). A 5-year backtest shows a typical error of ±293.1%, with 80% 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 →
2025130.0029
2026130.0029
2027130.0029
2028130.0029
2029140.0029

Franklin's Gull Survey Routes in North Dakota

Routes recording Franklin's 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 Rose87220241997
Lakota9920031968
Powers Lake7820231994
Carpio7020231969
Denbigh6020241968
Horsehead Lk5520241983
Niles5320241989
Loraine2820181982
Lakota 22520152010
Edgeley2320241980
Sheyenne Lk2320221986
Webster2120241989
Parshall2119951982
Regan2019971997
Dunn Center2019681968
Douglas Crk1220231984
Montpelier1020241996
Lake George920221968
Dickinson920132013
Sydney619681968
Bowesmont519951995
Braddock520221990
Danzig420141983
Emerado420151982
Walcott320071972

Franklin's Gull Population Trend in Other States

californiaidahokansasminnesotamontananebraskaoregonsouth-dakotautahwyoming

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