(1970) may be an exception. The basic 

 link between the mangrove leaf and higher 

 order consumers is provided by micro- 

 organisms (fungi, bacteria, Protozoa) 

 which colonize the decaying leaf and con- 

 vert them into a relatively rich protein 

 source (Odum 1970; Odum and Heald 1975a). 

 These decaying leaf fragments with asso- 

 ciated microorganisms are fed upon by a 

 group of omnivorous detritivores including 

 amphipods, mysids, cumaceans, ostracods, 

 chironomid larvae, harpacticoid and 

 calanoid copepods, snapping shrimp, 

 caridean and penaeid shrimp, a variety of 

 crabs, filter-feeding bivalves, and a few 

 species of fishes (Odum 1970; Odum and 

 Heald 1972; Odum and Heald 1975b). These 

 detritivores, in turn, are consumed by a 

 number of small carnivorous fishes, which 

 in turn, are consumed by larger 

 piscivorous fishes. The concept of man- 

 grove trophic structure is also discussed 

 in section 3.6. See Appendix B for 

 species specific dietary information. 



The tidal creeks studied by Nugent 

 (1970) on the western shore of Biscayne 

 Bay differ from the previously discussed 

 streams in the Everglades estuary. The 

 mouths of the Biscayne Bay creeks have 

 dense growths of sea grasses which con- 

 tribute sea grass detritus. The salini- 

 ties are considerably greater and the 

 streams are located only a few kilometers 

 from coral reefs, which are largely absent 

 on Florida's west coast, at least close to 

 shore. As a result, 23 species listed in 

 Appendix B were captured by Nugent (1970) 

 and are not recorded from riverine man- 

 grove habitat on the west coast of 

 Florida. Examples include several of the 

 grunts (Pomadasyidae), the gray trigger- 

 fish, Balistes capriscus , the barbfish, 

 Scorpaena brasiliensis , the scrawled box- 

 fish, Lactophrys quadricorni s , and the 

 snappers, Lutjanus apodus and L. synagris. 



Riverine mangrove communities and 

 associated tidal streams and rivers are 

 typified by the following families of 

 fishes: killifishes (Cypri nodontidae), 

 livebearers (Poeci 1 i idae), silversides 

 (Atherinidae), mojarras (Gerreidae), tar- 

 pon (Elopidae), snook (Centropomidae), 

 snappers (Lut jani dae) , sea catfishes 



(Ariidae), gobies (Gobi idae), porgys 

 (Sparidae), mullets (Mugilidae), drums 

 (Sci aenidae), and anchovies (Engraulidae). 

 The mangrove-lined streams and associated 

 pools are important nursery areas for 

 several marine and estuarine species of 

 gamefish. The tarpon, Megalops atlantica , 

 snook, Centropomus undecimalis , and lady- 

 fish, Elops saurus , utilize these areas 

 from the time they reach the estuary as 

 post-larvae, having been spawned offshore. 

 Gray snapper, Lutjanus g r i s e u s , 

 sheepshead, Archosargus probatocephalus , 

 spotted seatrout, Cynoscion nebulosus , and 

 red drum, Sciaenops ocellata , are re- 

 cruited to grass beds of shallow bays and 

 lagoons as post-larvae and enter the 

 mangrove-lined streams for the next sever- 

 al years (Heald and Odum 1970). Of these 

 species, only the spotted seatrout prob- 

 ably spawns in the estuary (Tabb 1966). 

 Other species of commercial or game impor- 

 tance which use the riverine fringing 

 habitat include crevalle jack, gafftopsail 

 catfish, jewfish, striped mojarra, barra- 

 cuda, Atlantic thread herring, and yellow- 

 fin menhaden (Odum 1970). 



7.3 FRINGING FORESTS ALONG ESTUARINE BAYS 

 AND LAGOONS 



Mangrove-fringed estuarine bays and 

 lagoons are exemplified by the Ten 

 Thousand Islands area and Whitewater Bay. 

 Quantitative fish data are available from 

 Fahkahatchee Bay (Carter et al. 1973; 

 Yokel 1975b; Seaman et al. 1973), Fahka 

 Union Bay (Carter et al. 1973), Rookery 

 Bay (Yokel 1975a), the Marco Island 

 Estuary (Weinstein et al. 1977; Yokel 

 1975a), and Whitewater Bay (Clark 1970). 

 Individual site characteristics are 

 summarized in Appendix A. All except 

 Fahka Union Bay contain significant 

 amounts of sea grasses. Macroalgae domi- 

 nate the benthic producers of Fahka Union 

 Bay. Studies by Reid (1954) and Kilby 

 (1955) near Cedar Key, Florida, were not 

 included in our summary because mangroves 

 are sparse in this area and no mention of 

 mangrove collecting sites were made by 

 these authors. Studies of Caloosahatchee 

 Bay (Gunter and Hall 1965) and of 

 Charlotte Harbor (Wang and Raney 1971) 



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