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| pical islands such as the Galapagos and New Caledonia. Many species breed in coastal colonies, with a preference for islands; one particular species, the grey gull, breeds in the interior of dry deserts far from water. Considerable variety exists in the Laridae family, and species may breed and feed in marine, freshwater, or terrestrial habitats. Most gull species are migratory, with birds moving to warmer habitats during the winter, but the extent to which they migrate varies by species. Some migrate long distances, notably Sabine's gull, which migrates from the Arctic coasts to wintering grounds off the west coasts of South America and southern Africa, and Franklin's gull, which migrates from Canada to winter off the west coast of South America. Other species move much shorter distances and may simply disperse along the coasts near their breeding sites. Gulls in the coat of arms of Haugesund A big influence on non-breeding gull distribution is the availability of food patches. Human fisheries especially have an impact, since they often provide an abundant and predictable food resource. Two species of gulls dependent on human fisheries are Audouin's gull (Ichthyaetus audouinii) and lesser black-backed gulls (Larus fuscus); their breeding distributions (especially the black-backed gull) are heavily impacted by human fishing discards and fishing ports. Other environmental drivers that structure bird habitat and distribution are human activity and climate impacts. For example, waterbird distribution in Mediterranean wetlands is influenced by changes in salinity, water depth, water body isolation and hydroperiod, all of which have been observed to affect the bird community structure in both a species- and guild-specific way. Gulls in part |