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Species · Alaska · BBS 2025 Release · 1966–2024

Glaucous-winged Gull Population Trend in Alaska

All statesWetland birds

Glaucous-winged Gull in Alaska has surged: up 214% on the route-weighted index since 1974.

+214%Since 1974TrendPercent 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 →
60Routes 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Glaucous-winged Gull Trends in AlaskaNotable 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 →

Glaucous-winged Gull has surged in Alaska: up 214% on the route-weighted index since 1974.

Glaucous-winged Gull Population Forecast in Alaska

If the recent trend holds, Glaucous-winged Gull in Alaska is projected to fall about 100% by 2029 — from 2.6 in 2024 to a central estimate of 0.00 (95% range 0.00–20). A 5-year backtest shows a typical error of ±37.9%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–2095% 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 →
±37.9%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, Glaucous-winged Gull in Alaska is projected to fall about 100% by 2029 — from 2.6 in 2024 to a central estimate of 0.00 (95% range 0.00–20). A 5-year backtest shows a typical error of ±37.9%, with 100% of held-out values landing inside the 95% band.19712029
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 →
20251.00.0021
20260.740.0021
20270.470.0021
20280.200.0020
20290.000.0020

Glaucous-winged Gull Survey Routes in Alaska

Routes recording Glaucous-winged Gull in Alaska.
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 →
Homer46319821977
Cape Nome6320241993
Kodiak 24620231985
Kalifonsky3020231982
Cold Bay (Short)2819921984
Cordova2120241983
Yakutat2120241993
Dillingham2020171993
Juneau1620241983
Adak1320011983
Mitkof Isle1220102009
Zimovia Strt1220241989
Kodiak1119841983
Togiak River1120051994
Sitka1120241993
Skagway1020241993
King Salmon820241993
Goodnews Bay820051999
Seward719841982
Ketchikan720191971
Dillingham (Short)719841984
Petersville619871987
Salmon Lake520242003
Cohoe520162012
Council420232019

Glaucous-winged Gull Population Trend in Other States

californiaoregonwashington

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