It formerly included the very similar Olrog's gull as a subspecies, but that bird occurs on the Atlantic coast of South America and is now accepted as Larus atlanticus.

The name of this bird commemorates the British explorer Sir Edward Belcher, who performed survey work on the Pacific coast of South America.

The sexes are similar in appearance, and in the breeding season, the adult has a white head and very pale grey neck and underparts.

[2] Breeding takes place from December onwards in small colonies of up to one hundred pairs.

For these reasons, despite its small total population size and limited range, the International Union for Conservation of Nature considers it to be of "least concern".