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Importance of Wetlands to Endangered and Threatened Specks (Kushlan, 1974), prevents natural invasion by aquatic plants such as coontail (Myriophyl- lunz sp.), bladderwort (Utricularia sp.), pondweeds (Potar~aogeton spp.), and "flags" (Thalia geniculata). The primary purpose of gator holes is to provide the alligator with sufficient water to sustain itself during periods of drought, generally from November to April. As the sur- rounding fresh waters recede, the hole becomes a refuge for many aquatic species, thus resulting in concentrations of Fish (as many as 23 species), crustaceans, and protozoa. The number of organisms inhabiting a gator hole can be phenomenal; Kushlan (1972) found densities of 1,600 fish and prawns per square meter in a gator hole in Big Cypress Swarnp. The high concentration of potential food is preyed upon by predatory species of mammals, birds, and reptiles which congregate along the adjacent perimeter of vegetation and bank. Scraps and feces of predators, in turn, fulfill nutrient requirements of species lower on the food chain. When spring rains return, the organisms trapped in gator holes repopulate the surrounding area, often with a spectacular burst of energy. The concentration of organisms in a small area can be vital to breeding cycles of pisci- vorous birds, such as some Ciconiifonnes (Carr, 1973; Kuslrlan, 1972). One example is that of the wood ibis (Mvcteria amerieana) in which reproduction is timed to coincide ~~Nith maximum concentration of fish in gator holes. Successful rearing of young requires vast numbers of small fishes which the parents obtain by moving their beaks back and forth in shallow water until contact is made with the prey. This method of feeding will work only if the prey are concentrated in a restricted area since the fishes are small and mobile and could easily otherwise escape. By rearing their young during the dry season, when the fish are collected in gator holes, selection has ensured that adequate prey will be available to satisfy the energy requirements of the young ibis. In abnormally wet years when fishes are not collected in such refugia, breeding activities may not begin or may be broken off, so that no successful reproduction occurs. Manipulation of water levels by !lams and dikes, as well as alteration of drainage patterns, can result in reduced concentra- tions of fish. The wood ibis, therefore, has declined through its former range in the United States. Alligators not only build Bator holes, they wander in search of food, moisture, and mates. Wandering has effects on wetland vegetation by keeping open narrow waterways in the glades and preventing colonization by red mangrove. Naturally occurring islands, such as bayheads, are also maintained by resident alligators and perhaps start on the rem- nants of alligator nests in the sawgrass. Craighead (1968) has provider' many insights into the importance of the alligator in maintaining the vegetational structure of the Everglades. The alteration of ancient drainage patterns with accompanying abnormal periods of drought and fires that destroy vegetation and peat, as well as the decline of the alligator in areas where it was formerly abundant, may have altered forever the wetland communities of southern Florida. The alligator is the top predator in its environment and may feed on almost any animal it can catch. Numerous studies in the literature confirm that arthropods, particularly crustaceans (Procambarus sp., Callinectes sp.), fish, birds, mammals (particularly muskrats, Ondatra zibethica, and nutria, Myocastor coypus), and snails (Pomacea paludosa) are main food items, depending on habitat and size class of alligator (Valentine, et al., 1972; McNease and Joanen, 1977; Fogarty and Albury, 1967; Giles and Childs, 1949), although correlation between prey choice and prey availability is not vYell understood. Of parti- cular interest is the relationship between alligators feeding on the apple snail, Pomacea 567