(table 4.4), and Butner and Brattstroni (1960) 

 described the migration of killifish into the marshes 

 on tidal cycles. Large redfish are often observed 

 foraging in marsh ponds and tidal creeks so shallow 

 that the dorsal fins of these fishes project out of the 

 water. 



In a recent study in southeastern Louisiana, 

 Hinchee (1977) found that small Gulf menhaden, 

 spawned offshore, moved through estuaries into fring- 

 ing marshes and swamps for several months before 

 they moved out into the estuarine waters as larger 

 fish (fig. 4-18). The habitats used by the juvenile men- 

 haden were fresh marsh and swamp forest habitats, 

 indicating that the nursery function is not confined 

 to sahne tidal wetlands. 



Table 4.4 Fish biomass in small marsh ponds com- 

 pared to open estuarine waters of 

 the Caminada Bay system, Louisiana 

 (Wagner 1973). 



Perhaps the most dramatic evidence of the im- 

 portance of the marsh as a food source and as a refuge 

 for small organisms is the report by Turner (1977a), 

 which showed that the harvest of shrimp is strongly 

 related to the area of estuarine marshland (fig. 4-19). 

 The relationship is much closer than that between 

 shrimp harvest and the area of inland open water. 

 It is also well documented that small shrimp migrate 

 into inland waters and marshes where they pass 

 througli the juvenile stage before emigrating to the 

 open Gulf (part 5). 



Different bird species use wetlands as a nesting 

 area in summer, as a wintering ground, or as a tem- 

 porary stopover area during spring and fall migration. 

 Shorebirds, wading birds, and many predatory birds 

 feed in both open water and wetland habitats. The 

 requirements of many such animals for different 

 habitats, at different life history stages, underline 

 the higli degree of interaction among coastal com- 

 munities, and show that the wetland-open water 

 system must be considered and managed as a whole. 



Area 



Small enclosed marsh pond 

 Small marsh pond with deep 

 channel to bay 



Open water 



Fish biomass 



(s/m^) 



46.1 



13.8 

 1-6 



Pond fish determined by chemical toxin; fish in open 

 water by trawl, gill net, and trammel net. 



4.2.7 CONSUMERS 



The previous sections have emphasized processes 

 that are common to all wetlands. In different wetland 

 habitats different species assume the same functional 

 roles. The species that are characteristic of each habi- 

 tat are discussed more fully in the following sections, 

 but summary tables are included here for perspective. 



— * 



o 



c 



CT 



35 n 



30 



25- 



20- 



15- 



10- 



5- 



□ 



"1^ 

 5 



Lake Stations 

 (Based on 237 



Menhaden) 



Marsh Stations 



(Based on 15927 Menhaden) 



i 



10 15 20 25 30 35 40 45 50 55 60 65 70 



75 80 85 90 95 100 



Length classes (mm) 



Figure 4-18. Length-frequency distribution of Gulf menhaden at marsh and lake stations in Lake Pontchartrain, 

 Louisiana (ilinchce 1977). 



170 



