Marine life live in the water column of large bodies of water and that cannot swim against a current. They provide a crucial source of food to many large aquatic organisms, such as fish and whales. These organisms include drifting or floating bacteria, archaea, algae, protozoa and animals that inhabit, for example, the pelagic zone of oceans, seas, or bodies of fresh water. Essentially, plankton are defined by their ecological niche rather than any phylogenetic or taxonomic classification. Though many planktonic species are microscopic in size, "plankton" includes organisms covering a wide range of sizes, including large organisms such as jellyfish. The
Everglades National Park roseate spoonbills ("Platalea ajaja"), ibises and brown pelicans ("Pelecanus occidentalis"), as well as limpkins ("Aramus guarauna") and snail kites that eat apple snails, which in turn feed on the sawgrass. The sloughs' availability of fish, amphibians, and young birds attract a variety of freshwater turtles, alligator ("Alligator mississippiensis"), water moccasin ("Agkistrodon piscivorus conanti"), and eastern diamondback rattlesnake ("Crotalus adamanteus"). Freshwater marl prairies are similar to sloughs but lack the slow movement of surface water; instead, water seeps through a calcitic mud called marl. Algae and other microscopic organisms form periphyton, which attaches to limestone. When it dries it turns into