Fam. Auk, Alcidae Rubund Creative Commons Attribution ShareAlike.	Fam. Gull, Laridae Rubund Creative Commons Attribution ShareAlike.
Fam. Skimmer, Rynchopidae "Skimmer Redux" by Terry Foote via Flickr, Creative Commons Attribution ShareAlike.	Fam. Skua, Stercorariidae "Pomarine Jaeger in Flight I" by Jomilo75 via Flickr, Creative Commons Attribution.
Fam. Tern, Sternidae "Royal Tern (Thalasseus maximus syn. Sterna maxima), Morro Strand State Beach, Morro Bay, CA" by Mikebaird via Flickr, Creative Commons Attribution.

Taxonomy:

Fam. Auk, Alcidae

Gen. Aethia (Add)

Aethia cristatella (Add)
Aethia psittacula (Add)
Aethia pusilla (Add)
Aethia pygmaea (Add)

Gen. Alca (Add)

Razorbill, Alca torda

Gen. Alle (Add)

Little Auk, Alle alle

Gen. Brachyramphus (Add)

Brachyramphus brevirostris (Add)
Brachyramphus marmoratus (Add)
Brachyramphus perdix (Add)

Gen. Cepphus (Add)

Cepphus carbo (Add)
Cepphus columba (Add)
Black Guillemot, Cepphus grylle

Gen. Cerorhinca (Add)

Cerorhinca monocerata (Add)

Gen. Fratercula (Add)

Atlantic Puffin, Fratercula arctica

Fratercula cirrhata (Add)
Fratercula corniculata (Add)

Gen. Pinguinus (Add)

Great Auk, Pinguinus impennis (Add)

Gen. Ptychoramphus (Add)

Ptychoramphus aleuticus (Add)

Gen. Synthliboramphus (Add)

Synthliboramphus antiquus (Add)
Synthliboramphus craveri (Add)
Synthliboramphus hypoleucus (Add)
Synthliboramphus scrippsi (Add)
Synthliboramphus wumizusume (Add)

Gen. Uria (Add)

Common Guillemot, Uria aalge

Brünnich's Guillemot, Uria lomvia

Fam. Gull, Laridae

Gen. Chroicocephalus (Add)

Chroicocephalus brunnicephalus (Add)
Chroicocephalus bulleri (Add)
Grey-hooded Gull, Chroicocephalus cirrocephalus (Add)
Chroicocephalus genei (Add)
Chroicocephalus hartlaubii (Add)
Chroicocephalus maculipennis (Add)
Chroicocephalus novaehollandiae (Add)
Chroicocephalus philadelphia (Add)
Black-headed Gull, Chroicocephalus ridibundus

Chroicocephalus scopulinus (Add)
Chroicocephalus serranus (Add)

Gen. Creagrus (Add)

Swallow-tailed Gull, Creagrus furcatus

Gen. Hydrocoloeus (Add)

Little Gull, Hydrocoloeus minutus

Gen. Ichthyaetus (Add)

Ichthyaetus audouinii

Ichthyaetus hemprichii (Add)
Ichthyaetus ichthyaetus (Add)
Ichthyaetus leucophthalmus (Add)
Ichthyaetus melanocephalus (Add)
Ichthyaetus relictus (Add)

Gen. Larus (Add)

European Herring Gull, Larus argentatus

Larus armenicus (Add)
Larus atlanticus (Add)
Larus belcheri (Add)
Larus cachinnans (Add)
Larus californicus (Add)
Common Gull, Larus canus

Larus crassirostris (Add)
Ring-billed Gull, Larus delawarensis

Larus dominicanus (Add)
Lesser Black-backed Gull, Larus fuscus

Larus glaucescens (Add)
Iceland Gull, Larus glaucoides (Add)
Larus heermanni (Add)
Glaucous Gull, Larus hyperboreus (Add)
Larus livens (Add)
Great Black-backed Gull, Larus marinus

Larus michahellis (Add)
Western Gull, Larus occidentalis

Larus pacificus (Add)
Larus schistisagus (Add)
Larus smithsonianus (Add)
Larus thayeri (Add)

Gen. Leucophaeus (Add)

Laughing Gull, Leucophaeus atricilla

Leucophaeus fuliginosus (Add)
Leucophaeus modestus (Add)
Leucophaeus pipixcan (Add)
Leucophaeus scoresbii (Add)

Gen. Pagophila (Add)

Ivory Gull, Pagophila eburnea

Gen. Rhodostethia (Add)

Ross's Gull, Rhodostethia rosea

Gen. Rissa (Add)

Rissa brevirostris (Add)
Black-legged Kittiwake, Rissa tridactyla

Gen. Saundersilarus (Add)

Saundersilarus saundersi (Add)

Gen. Xema (Add)

Sabine's Gull, Xema sabini (Add)

Fam. Skimmer, Rynchopidae

Gen. Rynchops (Add)

Indian Skimmer, Rynchops albicollis (Add)
African Skimmer, Rynchops flavirostris (Add)
Black Skimmer, Rynchops niger

Fam. Skua, Stercorariidae

Gen. Stercorarius (Add)

Stercorarius antarctica

Stercorarius chilensis (Add)
Pomarine Skua, Stercorarius longicaudus (Add)
South Polar Skua, Stercorarius maccormicki

Arctic Skua, Stercorarius parasiticus

Stercorarius pomarinus

Great Skua, Stercorarius skua

Fam. Tern, Sternidae

Gen. Anous (Add)

Anous minutus (Add)
Anous stolidus (Add)
Anous tenuirostris (Add)

Gen. Chlidonias (Add)

Chlidonias albostriatus (Add)
Chlidonias hybridus (Add)
Chlidonias leucopterus (Add)
Chlidonias niger (Add)

Gen. Gelochelidon (Add)

Gelochelidon nilotica (Add)

Gen. Gygis (Add)

White Tern, Gygis alba

Gygis microrhyncha (Add)

Gen. Hydroprogne (Add)

Hydroprogne caspia (Add)

Gen. Larosterna (Add)

Larosterna inca

Gen. Onychoprion (Add)

Onychoprion aleuticus (Add)
Onychoprion anaethetus (Add)
Onychoprion fuscatus (Add)
Onychoprion lunatus (Add)

Gen. Phaetusa (Add)

Phaetusa simplex (Add)

Gen. Procelsterna (Add)

Procelsterna albivitta (Add)
Procelsterna cerulea (Add)

Gen. Sterna (Add)

Sterna acuticauda (Add)
Sterna albifrons (Add)
Sterna albostriata (Add)
Sterna anaethetus (Add)
Sterna antillarum (Add)
Sterna aurantia (Add)
Sterna balaenarum (Add)
Sterna bengalensis (Add)
Sterna bergii (Add)
Sterna bernsteini (Add)
Sterna dougallii (Add)
Sterna elegans (Add)
Sterna forsteri (Add)
Sterna fuscata (Add)
Sterna hirundinacea (Add)
Common Tern, Sterna hirundo

Sterna lorata (Add)
Sterna maxima (Add)
Sterna nereis (Add)
Arctic Tern, Sterna paradisaea

Sterna repressa (Add)
Sterna sandvicensis (Add)
Sterna saundersi (Add)
Sterna striata (Add)
Sterna sumatrana (Add)
Sterna superciliaris (Add)
Sterna trudeaui (Add)
Sterna virgata (Add)
Sterna vittata (Add)

Gen. Thalasseus (Add)

Thalasseus bergii (Add)
Thalasseus elegans (Add)
Royal Tern, Thalasseus maximus

Thalasseus sandvicensis (Add)