BirdAnalyst
Species · BCR 4 · BBS 2025 Release · 1966–2024

Glaucous Gull In BCR 4

All regionsBCR 4Wetland birds

Glaucous Gull in BCR 4 has collapsed: down 100% on the route-weighted index since 1991.

-100%Since 1991TrendPercent 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 →
9Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
13YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 declinecomputed 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 Gull has collapsed in BCR 4: down 100% on the route-weighted index since 1991.

Routes In BCR 4

Routes recording Glaucous Gull in BCR 4.
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 →
HomerALASKA2531978
Kobuk River (Short)ALASKA51991
Skilak LakeALASKA31978
ColdfootALASKA22013
RubyALASKA22007
Hather CreekALASKA12018
Kanuti CanynALASKA12017
Mud RiverALASKA12017
Galena (Short)ALASKA12013

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