dark gulls, but have a fleshy cere above the upper mandible. They are strong, acrobatic fliers. Five species have been recorded in Maryland. Great skua, Stercorarius skua (R) South polar skua, Stercorarius maccormicki (R) Pomarine jaeger, Stercorarius pomarinus (R*) Parasitic jaeger, Stercorarius parasiticus (R*) Long-tailed jaeger, Stercorarius longicaudus (R) Auks, murres, and puffins Order: CharadriiformesFamily: Alcidae Alcids are superficially similar to penguins due to their black-and-white colors, their upright posture, and some of their habits; however, they are only distantly related to the penguins and are able to fly. Auks live on the open sea, only deliberately coming ashore to nest. Six species have been recorded in Maryland. Dovekie, Alle alle (R*) Common murre, Uria aalge (R*) Thick-billed murre, Uria lomvia (R) Razorbill, Alca torda (R*) Black guillemot, Cepphus columba (R) Atlantic puffin, Fratercula arctica (R*) Gulls, terns, and skimmers Order: CharadriiformesFamily: Laridae Gulls are typically medium-to-large birds, usually gray or white, often with black markings on the head or wings. They have stout, longish bills and webbed feet. The large species take up to four years to attain full adult plumage, but two years is typical for small gulls. Terns are in general medium-to-large birds, typically with gray or white plumage, often with black markings on the head. They have longish bills and webbed feet. They are lighter bodied and more streamlined than gulls, and look elegant in flight with long tails and long narrow wings. Skimmers are tropical and subtropical species. They have an elongated lower mandible. They feed by flying low over the water surface with the lower mandible skimming the water for small fish. Thirty-two confirmed species of Laridae, and one species of questionable origin, have been recorded in Maryland. Black-legged kittiwake, Rissa tridactyla (R*) Sabine's gull, Xema sabini (R) Bonaparte's gull, Chroicocephalus philadelphia Black-headed gull, Chroicocephalus ridibundus (R*) Little gull, Hydrocoloeus minutus (R*) Silver gull, Chroicocephalus novaehollandiae (QO) (not on the AOS Check-list; scientific name and placement are per Clements) Ross's gull, Rhodostethia rosea (R) Laughing gull, Leucophaeus atricilla (R*) Franklin's gull, Leucophaeus pipixcan (R) Black-tailed gull, Larus crassirostris (R) Common gull, Larus canus (R) Ring-billed gull, Larus delawarensis California gull, Larus californicus (R) Herring gull, Larus argentatus Yellow-legged gull, Larus michahellis (R) Iceland gull, Larus glaucoides (R*) Lesser black-backed gull, Larus fuscus Glaucous gull, Larus hyperboreus (R*) Great black-backed gull, Larus marinus (R*) Kelp gull, Larus dominicanus (R) Sooty tern, Onychoprion fuscatus (R*) Bridled