Franklin's gull, Leucophaeus pipixcan Short-billed gull,Larus brachyrhynchus Ring-billed gull, Larus delawarensis Western gull, Larus occidentalis (S) California gull, Larus californicus Herring gull, Larus argentatus Iceland gull, Larus glaucoides Lesser black-backed gull, Larus fuscus (S) Slaty-backed gull, Larus schistisagus (S) Glaucous-winged gull, Larus glaucescens (H) Glaucous gull, Larus hyperboreus Great black-backed gull, Larus marinus (S) Least tern, Sternula antillarum (S) Caspian tern, Hydroprogne caspia Black tern, Chlidonias niger Common tern, Sterna hirundo Arctic tern, Sterna paradisaea Forster's tern, Sterna forsteri Loons Order: GaviiformesFamily: Gaviidae Loons, known as divers in Europe, are aquatic birds the size of a large duck, to which they are unrelated. Their plumage is largely grey or black, and they have spear-shaped bills. Loons swim well and fly adequately, but, because their legs are placed towards the rear of the body, are almost helpless on land. Red-throated loon, Gavia stellata Pacific loon, Gavia pacifica Common loon, Gavia immer Yellow-billed loon, Gavia adamsii (S) Frigatebirds Order: SuliformesFamily: Fregatidae Frigatebirds are large seabirds usually found over tropical oceans. They are large, black, or black-and-white, with long wings and deeply forked tails. The males have coloured inflatable throat pouches. They do not swim or walk and cannot take off from a flat surface. Having the largest wingspan-to-body-weight ratio of any bird, they are essentially aerial, able to stay aloft for more than a week. Magnificent frigatebird, Fregata magnificens (S) Cormorants and shags Order: SuliformesFamily: Phalacrocoracidae Cormorants are medium-to-large aquatic birds, usually with mainly dark plumage and areas of coloured skin on the face. The bill is long, thin and sharply hooked. Their feet are four-toed and webbed. Double-crested cormorant, Nannopterum auritum Pelicans Order: PelecaniformesFamily: Pelecanidae Pelicans are very large water birds with a distinctive pouch under their beak. Like other birds in the order Pelecaniformes, they have four webbed toes. American white pelican, Pelecanus erythrorhynchos Herons, egrets, and bitterns Order: PelecaniformesFamily: Ardeidae The family Ardeidae contains the bitterns, herons, and egrets. Herons and egrets are medium to large wading birds with long necks and legs. Bitterns tend to be shorter necked and warier. Unlike other long-necked birds such as storks, ibises, and spoonbills, members of this family fly with their necks retracted. American bittern, Botaurus lentiginosus Least bittern, Ixobrychus exilis (S) Great blue heron, Ardea herodias Great egret, Ardea alba Snowy egret, Egretta thula (S) Little blue heron, Egretta caerulea (S) Tricolored heron, Egretta tricolor (S) Cattle egret, Bubulcus ibis Green