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SALINE (20-35 ppD 



BAflATAfllA BAY 



BRACKISH (0.5-20 ppl) 



LITTLE LAKE -LAKE SALVADOR 



FRESH (0-0 5 ppt) 



LAKE CATAOUATCME-LAC DES ALLEMANOS 



Figure 69. Seasonal use of wetlands by migratory birds, shellfish, and fish. 



large numbers. They disappear during the 

 winter when they migrate south. 



Similarly, nektonic species appear to 

 partition the marsh ponds and creeks 

 seasonally. The most abundant commercial 

 species peak in ^y and June (brown 

 shrimp), October to December (white 

 shrimp), and March to May (croaker and 

 menhaden). The top carnivores, spotted 

 seatrout and red drum, reach greatest 

 densities in September and October. Up in 

 the shallow marsh ponds, the year-round 



residents peak in early spring (Ruebsamen 

 1972). The hot months of July and August 

 seem to be the periods of least activity 

 in the marsh, perhaps because many species 

 move into deeper, cooler bay waters during 

 that time. 



The migratory habits of the many 

 species that inhabit the delta marshes 

 emphasize the importance of inanagement 

 objectives that take into account the high 

 degree of coupling of the marsh with other 

 ecosystems. Marshes cannot be managed in 

 isol ation. 



83 



