There are 4 families, 6 genera and 15 species of Suliformes according to Eastern North America. Members of this order are Cormorants, Anhinga, Booby, Gannets, and Frigate birds. They are medium to large sea-birds usually found over tropical oceans. They prefer fresh water wetlands, ponds, rivers for habitat. They are mostly fish and small aquatic animal eaters.

Doubled crested Cormorant

v        Cormorants are large aquatic birds, usually with mainly dark plumage and areas of colored skin on the face. Their bill is long, thin, and sharply hooked. Their feet are four-toed and webbed, a distinguishing feature of the Suliform order. They are colonial nesters, using trees, rocky islets, or cliffs. The eggs are a chalky-blue colour. There is usually one brood a year. Representative species include Double crested Cormorant, Great Cormorant and Neotropic Cormorant.

Anhinga

v        Anhinga, according to Peterson field guide are similar to Cormorants, but neck snakier, bill more pointed and tail much longer. The Anhinga sometimes called Snakebird, Darter, American Darter, or Water Turkey, is a water bird of the warmer parts of the Americas. The word anhinga comes from the Brazilian Tupi language and means devil bird or snake bird for its habit of swimming with just its long head and neck sticking out of the water. It will perch for long periods with its wings spread to allow the drying process, as do cormorants. If it attempts to fly while its wings are wet, it has great difficulty getting off the water and takes off by flapping vigorously while "running" on the water.                            

Red footed Booby

Brown Booby

    Gannets and Booby are medium-large coastal seabirds that plunge-dive for fish. They closely related to the booby. The gannets are large black and white birds with yellow heads. They have long pointed wings and long bills. Northern gannets are the largest seabirds in the North Atlantic, with a wingspan of up to 2 meters. They hunt fish by diving from a height into the sea and pursuing their prey underwater. They are colonial breeders on islands and coasts. They normally lay one or more chalky-blue eggs on the ground or sometimes in a tree nest. Representative species are Masked Booby, Brown Booby, and Red footed Booby.

Magnificent Frigatebirds

v        Frigatebirds are large, black or black-and-white, with long wings and deeply forked tails. The males have inflatable colored throat pouches. They do not swim or walk, and cannot take off from a flat surface. Having the largest wingspan-to-weight ratio of any bird, they are essentially aerial, able to stay aloft for more than a week. They are also sometimes called Man of War birds or Pirate birds. They are seasonally monogamous, and nest colonially. A single egg is laid each breeding season. The duration of parental care in frigatebirds is the longest of any bird.

Sources:
Wikipedia
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Peterson field guide