more prominent members of this fish 

 community are the versatile cyprino- 

 donts (killifishes) and Poeciliids 

 (live bearers) (McPherson 1971, Odum 

 et al. 1982). 



Riverine forests, which gener- 

 ally connect the freshwater marshes 

 with the open waters of the estu- 

 arine zones, are characterized by a 

 fish community that seasonally 

 oscillates in response to salini- 

 ties, temperatures, migratory pat- 

 terns, and runoff. During fresh- 

 water flooding the fauna often con- 

 tains numerous Everglades marsh and 

 slough species such as the Florida 

 gar, sunfish, large mouth bass, and 

 catfish. As flooding subsides, 



freshwater species retreat upstream 

 and the fauna is gradually replaced 

 by more marine species such as jew- 

 fish, stingrays, needlefish, and 

 jacks. Temperature oscillations 



tend to cause some shallow water 

 species to move out into more 

 stable, deeper waters during the 

 winter months (Odum et al. 1982). 



The individual life history 

 patterns of fish species also in- 

 fluence faunal composition in the 

 riverine mangrove community. Sea- 

 sonal movements offshore to spawn 

 and subsequent larval and post lar- 

 val recruitment are involved in the 

 distribution and abundance patterns 

 of mullet, grey snapper, sheepshead, 

 spotted sea trout, red drum, silver 

 perch, and many others. 



The estuarine bay fringing 

 community is characterized by large 

 numbers of a relatively few species. 

 Working in Whitewater Bay, Clark 

 (1971) reports that two species, the 

 silver jenny ( Eucinostomus quia ) and 

 the pinfish ( Laqodon rhomboides ), 

 constitute 62.7% of the total catch. 

 Odum et al. (1982) divide this fish 

 community into two parts, a benthic 

 habitat dominated by the drums. 



mojarras, and snappers, and a mid to 

 upper water habitat dominated by 

 anchovies, herrings, and needle- 

 fishes. 



At least three of the studies 

 on estuarine fishes of the area have 

 attempted to correlate physical, 

 chemical, and biological conditions 

 to fish abundance. Though often 

 touted as a "factor" in determining 

 estuarine animal abundance, salinity 

 seldom exhibits any clear cut influ- 

 ence on fish catches in the present 

 study area (Roessler 1968, Jannke 

 1971). This is probably due to the 

 fact that salinity itself is a 

 simple response to the freshwater 

 runoff of the watershed rather than 

 a causal factor in fish reproductive 

 physiology. Causal factors are 



perhaps better approximated by 

 Roessler's findings that catch rates 

 are most often correlated with sea- 

 son and rainfall and that tempera- 

 ture often interacts with season and 

 rainfall to affect catches. 



Clark (1971) reports definite 

 patterns of seasonal abundance in 

 many fishes. He attributes most of 

 this seasonality to the classical 

 model of fish utilization of estu- 

 aries; that is, spawning offshore 

 leading to a peak influx of juve- 

 niles at one time of the year and 

 later in the year another peak cor- 

 responding to a spawning run back 

 offshore. He concludes that corre- 

 lations between catch rates and 

 environmental variables are often a 

 function of specific life histories 

 rather than gross evnironmental 

 parameters such as salinity. 



In general, many of the estu- 

 arine fish species exhibit a pattern 

 of juvenile distribution in the 

 upper estuaries, and later as adults 

 they gradually shift downstream and 

 eventually spawn offshore. Clark 

 (1971) suggests that the generally 



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