Number of coastal Herring Gull populations have reduced markedly in recent years. The breeding gull colony of the South Walney and Piel Channel Flats Site of Special Scientific Interest (SSSI), within the Morecambe Bay and Duddon Estuary potential Special Protection Area (pSPA), is of national and intermational importance for its number of Herring Gull Larus argentatus and Lesser Black-backed Gull Larus fuscus.