Belcher's Gull

Belcher's gull, also known as the band-tailed gull, is a medium-sized member of the Laridae family. It is characterized by a blackish mantle, a white head and underparts, and a distinctive black band on its otherwise white tail. The bill is a striking yellow with a red and black tip. During the non-breeding season, adults sport a brownish-black head with a white eye-ring, while juveniles display a mottled brown and white plumage until they reach maturity in their third year.

Identification Tips

When identifying Belcher's gull, look for the broad black subterminal band on the tail, which is a key diagnostic feature. The adult breeding plumage includes a white head, pale grey neck, and underparts, with a greyish-black mantle and back. The wings have black coverts and primaries, and dark grey secondaries with white tips. The yellow legs and feet, along with the yellow bill with its red and black tip, are also notable. In contrast to the kelp gull, Belcher's gull lacks the small white tip on the black wing and has the unique black tail band.

Habitat

This species is found along rocky shores, bays, and offshore islands, where it is influenced by the nutrient-rich Humboldt Current.

Distribution

Belcher's gull graces the Pacific coast of South America, with its range stretching from northern Peru to northern Chile.

Behaviour

Belcher's gull is a non-migratory bird that forages several kilometers offshore and also feeds on rocky shores during low tide. It is known to be an opportunistic feeder, often harassing Guanay cormorants until they regurgitate their catch, which the gull then swiftly consumes.

Breeding

The breeding season commences in December, with small colonies of up to one hundred pairs nesting in scrapes in the sand or among rocks near the high tide line. Clutches typically consist of three eggs, pale in color with dark olive blotches.

Diet and Feeding

An omnivore and scavenger, Belcher's gull's diet includes fish, crabs, molluscs, carrion, and, seasonally, the eggs and nestlings of other seabirds.

Conservation status

With a population under ten thousand individuals and a distribution range of 280,000 square kilometers, Belcher's gull is considered to be of "Least Concern" by the International Union for Conservation of Nature. Human persecution has lessened, and the population appears to be on the rise.