and water temperature were correlated with intensity and timing of movement. 

 The pattern of migration was different from that reported on other rivers, 

 reflecting the relatively stable flow regime of the chalk stream. 



157. SOULE, D.F., "Marine Studies of San Pedro Bay, California: Part II: 

 Potential Effects of Dredging on the Biota of Outer Los Angeles Harbor," 

 University of Southern California, Institute of Marine and Coastal Studies, 

 Los Angeles, Calif., 1976. 



Specific investigations discussed in this report are: the potential 

 ecological effects of hydraulic dredging in Los Angeles Harbor; resuspended- 

 sediment elutriate studies on the northern anchovy (Engrautis mordax) ; the 

 effects of Los Angeles Harbor sediment elutriate on the California killfish 

 (Fundulus parvipinnis) and white croaker (Genyonemus lineatus) ; the toxicity 

 and heavy metals in three species of Crustacea from the harbor sediments; the 

 bioassay and heavy metal uptake investigations of resuspended sediment on two 

 species of polychaetous annelids; biomass and recolonization studies in the 

 outer Los Angeles Harbor; and the water quality evaluation of dredged material 

 disposal from Los Angeles Harbor. 



158. ST. AMANT, L.S., "A Discussion of the Effects of Shell Dredging on the 

 Ecosystems of Northern Gulf of Mexico Embayments," Symposium on Ocean 

 Mining^ OSM II, World Dredging Conference Association, 1973, pp. 139-149. 



Shell dredging on the coast of Louisiana has not caused serious effects 

 on the overall fishery, because disturbances associated with dredging are 

 highly localized and confined to within several hundred yards of the operating 

 dredge. The local disturbance to free-swimming marine life appears to be transi- 

 tory and disappears within a few hours after the dredging ceases. Dredging 

 can be demonstrated to have a direct physical effect on live oyster reefs by 

 direct destruction or severe siltation if allowed to operate in or very 

 near such reefs. Benthic organisms in the path of the dredge will obviously 

 be severely disturbed or destroyed, but these short-lived, rapidly reproducing 

 animals tend to repopulate the area within a reasonable length of time after 

 dredging is completed. Dredging can be conducted without harm to the fish 

 and shellfish industries if it is properly regulated and supervised. 



159. STERN, E.M., and STICKLE, W.B., "Effects of Turbidity and Suspended 

 Material in Aquatic Environments: Literature Review," Technical Report 

 D-78-21, Dredged Material Eesearah Program, U.S. Army Engineer Waterways 

 Experiment Station, Vicksburg, Miss., June 1978. 



This literature reviews the effects of turbidity and suspended material 

 in aquatic environments covering the following subjects: definitions, units of 

 measure and methods of measurement; origins; and the effects on aquatic environ- 

 ments . 



The literature indicates that turbidity and suspended solids conditions 

 typically created by most dredging and disposal operations are of short duration 

 and are unlikely to produce severe or irreversible ecological effects. The 

 possible exceptions to this generalization are coral reefs and other communities 

 that are especially sensitive to turbidity. Any possible effects of turbidity 

 and suspended material in aquatic environments may be minimized further by 

 careful selection of disposal sites keying operations to seasonal cycles in 

 biological activity and special consideration to areas that serve as nursery 

 grounds . 



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