fine to coarse sands. Some channels are characterized by eelgras-s patches 

 with subsequent higher percentages of fine-grained sediment. Preliminary 

 studies by the U.S. Army Engineer Division, New England, have concentrated on 

 evaluation of dredging effects on turbidity, dissolved oxygen, and mobiliza- 

 tion of trace metal constituents. Four projects have been selected for compar- 

 ison of predredging and postdredging impacts on benthic communities. 



29. CLARK, J., et al., "Studies of Estuarine Dependence of Atlantic Coastal 

 Fishes, Data Report II: Southern Section, New River Inlet, North Carolina, 

 to Palm Beach, Florida," Technical Paper No. 59, U.S. Bureau of Sport 

 Fisheries and Wildlife, Washington, D.C., 1970. 



Studies conducted by the Sandy Hook Marine Laboratory determined the pro- 

 portion of young, economically important Atlantic species of fish that enter 

 estuaries their first year. The investigators surveyed the Atlantic Continen- 

 tal Shelf to locate the spawning areas and the season in which to follow the. 

 movements of larval and juvenile stages. This report presents temperature, 

 salinity, zooplankton volume, and the surface meter net collection of juvenile 

 fish data made on four cruises from New River, North Carolina, to Palm Beach 

 Florida, during the second year of fieldwork. 



30. CONGDON, J.C., "Fish Populations of Channelized and Unchannelized Sections 

 of the Chariton River, Missouri," Stream Channelization: A Symposium, 

 Special Publication No. 2, American Fisheries Society, Dec. 1971, pp. 52-62. 



This study determines fish losses resulting from stream channelization on 

 the Chariton River, Missouri. In the unchannelized section, 21 fish species 

 were found compared with 13 species in the channelized section. The standing 

 crop of fish in the unchannelized section was estimated to be 138 kilograms per 

 acre compared with 24 kilograms per acre in the channelized section, an 83- 

 percent reduction. In both the channelized and unchannelized sections carp, 

 river carpsuckers, and channel catfish were the dominant species. The standing 

 crop of catchable fish in the unchannelized section was estimated to be 85 

 kilograms per acre compared with 12 kilograms per acre in the channelized sec- 

 tion, an 86-percent reduction. There were six species of catchable-size fish 

 in the unchannelized section compared with four in the channelized section. 



31. CONNER, W.G., and SIMON, J.L.,"The Effects of Oyster Shell Dredging on an 

 Estuarine Benthic Community," Estuax'ine and Coastal Marine Science^ Vol. 

 9, No. 6, Dec. 1979, pp. 749-758. 



This paper describes the effects of physical disruptions associated with 

 dredging fossil oystershell on the benthos. Two dredged areas and one undis- 

 turbed control area in Tampa Bay, Florida, were quantitatively sampled before 

 dredging and for 1 year after dredging. The immediate effects of dredging on 

 the soft-bottom community were reductions in the numbers of species (40-percent 

 loss), densities of macrofauna (65-percent loss), and total biomass of inverte- 

 brates (90-percent loss). During the 6 to 12 months after dredging, an analysis 

 showed no difference between the dredged and control areas in number of species, 

 densities, or biomass. Community overlap between dredged and control areas was 

 reduced directly after dredging, but after 6 months the predredging level of 

 similarity was regained. 



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