LC
Western Gull Larus occidentalis



Family: Laridae (Gulls, Terns, Skimmers)

Authority: Audubon, 1839

Red List Category

Sources: Esri, HERE, Garmin, Intermap, Increment P Corp, GEBCO, USGS, FAO, NPS, NRCAN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), © OpenStreetMap contributors and the GIS User Community. Powered by Esri
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Justification of Red List category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population size: unknown

Population trend: increasing

Extent of occurrence (breeding/resident): 656,000 km2

Country endemic: no

Attributes
Realm - Nearctic
IUCN System - Marine

Recommended citation
BirdLife International (2024) Species factsheet: Western Gull Larus occidentalis. Downloaded from https://datazone.birdlife.org/species/factsheet/western-gull-larus-occidentalis on 22/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 22/12/2024.