109. McCLEAVE, J.D., "Rhythmic Aspects of Estuarine Migration of Hatchery- 

 Reared Atlantic Salmon {Salmo salar) Smolts," Journal of Fisheries 

 Biology, Vol. 12, No. 6, June 1978, pp. 559-570. 



Seasonal, diel and tidal rhythmic activities of hatchery-reared Atlantic 

 salmon (Salmo salar) smolts migrating through a large estuary were studied by 

 ultrasonic tracking of 46 individuals during two seasons. Prior to 10 May 

 each year most smolts were inactive and remained nearshore in shallow water. 

 After 10 May nearly all smolts moved away from the release point into 

 swift water and made rapid seaward progress. Initiation of migration each 

 year occurred when the river and hatchery water temperatures rose above 9° 

 Celsius. Migration in the estuary was largely passive drift, and as a result 

 there were distinct tidal rhythms of groundspeed (swimming) and net seaward 

 travel. There were no diel rhythms in groundspeed or net seaward travel. 



110. MENZEL, R.W., "Effect of Man's Activities on Estuarine Fisheries," Under- 

 water mturalist. Vol. 7, No. 2, 1971, pp. 19-31. 



The function and the importance of an estuary are discussed. Adverse 

 effects by man as the result of dredging and filling, damming of rivers, and 

 pollution are also discussed. Emphasis is placed on the adverse effects on 

 oysters, shrimp, spotted sea trout, and striped bass. 



111. MIDDLE ATLANTIC COASTAL FISHERIES CENTER, "An Environmental Survey of 

 Effects of Dredging and Spoil Disposal, New London, Connecticut," In- 

 formal Report No. 107, U.S. National Marine Fisheries Service, Highlands, 

 N.J., Apr. 1976. 



The Middle Atlantic Coastal Fisheries Center presented comparative data 

 on benthic macrofauna populations of June 1974 versus June 1975, and October 

 1974 versus October 1975. At a station representing the original disposal 

 point, significant decreases (according to 95 percent confidence limits) 

 were found between June 1974 and June 1975 in the number of individuals (N) , 

 number of species (S) and Shannon-Weaver species diversity (H'). Significant 

 decreases in the number of individuals were also found at stations located 

 0.5 nautical mile southeast and northwest of the disposal buoy, and at a control 

 station 2 nautical miles northwest of the buoy; there was a significant increase 

 in the number of individuals at a station 1 nautical mile west-northwest of the 

 disposal buoy. No species had systematic increases or decreases which might 

 dictate their use as indicators of spoiling impacts. Changes in the number 

 of species between June 1974 and June 1975 were slightly smaller than those for 

 the number of individuals, though patterns of change for the two parameters 

 were identical. 



Preliminary comparisons of October 1974 versus October 1975 samples again 

 revealed apparently random, rather than spoil-related, changes outside of the 

 spoil pile itself. Recolonization of the spoils was well underway by October 

 1975; the number of individuals, species, and the Shannon-Weaver species diver- 

 sity index were all significantly higher than values that had been found in the 

 fresh spoils a year earlier. Amphipod crustaceans were the most abundant of 

 the colonizing forms because they had been in the predisposal sediments. Re- 

 appearance of these species may imply that (a) the dominant benthos can tolerate 

 the spoil materials, (b) an eventual return to a near natural assemblage can 

 be expected on the spoil piles, and (c) the tubes of these organisms may aid 

 in stabilizing the spoil against erosion. It is also noteworthy that communi- 

 ties of the amphipods, which are known to be very important in the diets of the 



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