noted by Dineen in fishes utilizing 

 the Eleocharis/blue-green algal mat 

 community. As flood waters season- 

 ally recede, the algal mat spreads 

 over the water surface, providing 

 shade for the shallow water inhab- 

 itants. Here, bass as large as 

 3.2 kg (7 lbs) have been found in as 

 little as 0.3 m (1 ft) of water. 



Optimum fish production appears 

 to be a function of the oscillation 

 of water levels rather than extremes 

 of either dry or wet conditions. 

 Excessive drought forces many marsh 

 inhabitants into ponds and sloughs 

 where predation often reaches the 

 frenzy stage. Fish kills may also 

 be frequent under such conditions. 



If water levels remain exces- 

 sively high over an extended time, 

 conditions may also become less than 

 optimum for the fish community (and 

 the sport fisherman). The normally 

 drought-stressed community tends to 

 spread out through the marshes, 

 leading to an increase of larger 

 predatory types in usually safe 

 refuges far from canals (Kushlan 

 1976). Simultaneously, high waters 

 may also stimulate the buildup of a 

 soupy ooze in the marshes. As 



drought conditions then begin, this 

 ooze creates a water/mud mixture 

 that may kill fish through suffoca- 

 tion even though water levels are 

 still adequate (Crowder 1974). 



A number of exotic species, 

 particularly aquarium rejects and 

 escapees such as oscars and gold- 

 fish, have been observed near the 

 National Park boundaries (Dineen 

 1974). The walking catfish ( Clarias 

 batrochus ) and the pike killifish 

 ( Belonesox belizanus ) are also re- 

 ported near the study area though 

 not yet observed within it. Two 

 rather peculiar members of the 

 freshwater fish fauna are the tarpon 

 ( Meqalops atlantica ) and the common 



snook ( Centropomus unidecimalis ) 

 which have apparently gained access 

 to freshwaters by moving upstream 

 via drainage canals. The only true 

 South American exotic is the black 

 acara ( Aequidens portaleqrensis ) 

 reported from alligator ponds (Kush- 

 lan 1972) and canals (Dineen 1974, 

 SFRC 1980). 



6.24 AMPHIBIANS AND REPTILES 



Eighteen (18) species of amphi- 

 bians and forty-seven (47) species 

 of reptiles are listed from the 

 terrestrial and freshwater wetlands 

 of the lower Everglades (Table 26) 

 (SFRC 1980). As a group, the 

 amphibians range over all habitats, 

 though many restrict themselves to a 

 limited set of conditions. In the 

 marshes and prairies one is likely 

 to find the greater siren and Ever- 

 glades dwarf siren, as well as a 

 number of frogs including the pig 

 frog, the Florida cricket frog, and 

 the southern leopard frog. In the 

 hammocks and pine flatwoods, the 

 eastern spadefoot toad and the oak 

 toad, as well as the Florida chorus 

 frog and the tree frogs are common 

 amphibian inhabitants (Carr and Goin 

 1969). 



Like many of the fishes, the 

 amphibians often possess a burrowing 

 capacity and an ability to enter a 

 state of aestivtion that helps them 

 survive droughts. If the drought is 

 not so severe as to remove essential 

 moisture from deep in the soil, the 

 amphibians have a chance of surviv- 

 ing. This burrowing capacity plays 

 an important role, not only in 

 amphibian survival, but also in the 

 survival of other species that may 

 coinhabit with them (Tabb 1963, 

 Kolipinski and Higer 1969). 



The 46 species of reptiles 

 listed in Table 26 include 9 tur- 

 tles, 10 lizards, 25 snakes, and 



135 



