STRUCTURAL MARSH MANAGEMENT EFFECTS ON COASTAL FISHES AND CRUSTACEANS

Structural marsh management, using levees and water-control structures , is used in the coastal zone for many objectives, for example, to red uce marsh loss, to enhance waterfowl habitat, to revegetate open-water areas, and to reduce saltwater intrusion. The literature was evaluate d to categorize structural marsh management and to determine some of i ts effects on fishes and crustaceans. Structural marsh management had positive effects on standing stock of most resident organisms and nega tive effects on marine-transient organisms. Emigration was negatively affected for both resident and marine-transient organisms. Techniques such as opening structures at critical migration times, designing stru ctures that offer the greatest management flexibility, and using struc tures to create a flow-through system could reduce these impacts. More effort should be put into monitoring managed areas to determine if th e objectives are being met and to evaluate the effects on fishes and c rustaceans. Although frequent manipulation could reduce these impacts, the costs and problems incurred may outweigh the anticipated benefits .