which created an unsuitable habitat for the mussel. After 2 years a population 

 of M. aattfovn-ianus was still present on the jetties at Playa Del Rey marina. 

 The difference in population of M. aatifornianus at the two marinas was not 

 explained. 



140. REYNOLDS, T.D., HANN, R.W., Jr., and PRIEBE, W.F., "Benthic Oxygen Demands 

 of Houston Ship Channel Sediments," Sea Grant Publication TAMU-SG-73-204, 

 Texas A & M University, College Station, Tex., 1973. 



This research was to determine the benthic oxygen demand of the sediment 

 deposits in the Houston ship channel for use in modeling. The scope of the 

 study included: (a) collection of bottom samples; (b) determining the char- 

 acteristics of the sludge, such as biochemical oxygen demand (BOD) , heavy 

 metals, etc.; (c) use of galvanic oxygen cells in determining the oxygen 

 uptake rates in grams of oxygen per hour per square meter, or other units; 

 (d) determination of the benthic demands at different temperatures to obtain 

 a demand versus temperature correlation; and (e) the determination of mixing 

 effects. 



141. RINGO, R.D., "Distribution and Abundance of Postlarval and Early Juvenile 

 Stages of the Brown Shrimp in Galveston Bay, Texas," Proceedings of 



the 18th Annual Conference of the Southeastern Association of Game and 

 Fish Commissioners, Oct. 1964. 



The early life history of the brown shrimp (Penceus aztecus)±n Galveston 

 Bay was investigated during 1963 and 1964. Postlarvae, after entering from the 

 gulf, were most abundant in the channels and deeper waters as they moved into 

 the upper reaches of the estuary. In each season of study, they were observed 

 to spread throughout the estuary and become concentrated in surrounding marshes 

 and bayous within about 2 weeks of the first entry. After spending 2 to 4 

 weeks in these peripheral areas, where they grew rapidly, the young shrimp, 

 now juveniles, once again dispersed throughout the estuary before eventually 

 returning to the gulf. Observations also indicated that the estuarine life 

 history phase of the brown shrimp is quite variable, with its duration probably 

 being related in large measure to the prevailing water temperature. 



142. RITCHIC, D.E., Jr., and KOO, T.S., "Hydrographic and Ecological Effects 

 of Enlargement of the Chesapeake and Delaware Canal. Appendix VIII. 

 Fish Movements, Maryland Study," Report No. NRI-REF-74-42, University 

 of Maryland, National Resources Institute, Solomons, Md., Sept. 1973. 



A summary is given of the results of a massive fish tagging operation 

 in the C and D Canal region in 1971-73. Direct evidence was found that fish 

 either move within or migrate back and forth through the canal. 



143. ROGERS, R.M., and DARNELL, R.M., "The Effects of Shell Dredging on the 

 Distribution of Meiobenthic Organisms in San Antonio Bay, Texas," 

 Environmental Impact Assessment of Shell Dredging in San Antonio Bay, 

 Texas, Vol. Ill, App. BIO-B, Texas A & M Research Foundation, College 

 Station, Tex., Sept. 1973, pp. 159-167. 



The present study has demonstrated that dredge cuts reduce the population 

 of meiobenthic animals to about one-third of their former levels and that 

 recovery is only above 80 percent complete more than a decade later. The 

 study has further pointed to the fact that modification of the particle struc- 

 ture of the sediments is probably the prime causative factor. Once a new 

 dredge cut Is made, it is gradually filled with waterborne suspended matter 



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