Is an increase in gull numbers responsible for limiting Atlantic Puffin Fratercula arctica numbers on Burhou, Channel Islands?

Abstract

This study investigated whether increased numbers of Larus gulls on the English Channel Island of Burhou restrict or endanger the island’s Atlantic Puffin Fratercula arctica population. About 120 breeding pairs of Atlantic Puffins in 2005–07 indicated little change in numbers since 1980, although a large decline occurred between 1950 and 1980. Numbers of Great Black-backed Gulls Larus marinus have changed little since 1969 but their direct predation on the reduced population of Atlantic Puffins was a considerable addition to adult mortality rates. Kleptoparasitic attacks by a greatly increased population of Lesser Black-backed Gulls L. fuscus, and by Herring Gulls L. argentatus, were probably too infrequent and too unsuccessful to affect Atlantic Puffin breeding success. When a large Atlantic Puffin population is reduced, predation by Great Black-backed Gulls and reduced recruitment caused by high breeding densities of gulls may prevent recovery of that population.