1528 



Raymont, J. E. G. 1976. 



The introduction of new species in habitats of heated effluents. In 

 Harvesting Polluted Waters. 0. Devik (ed.) . Plenum Press, New York: 

 185-199. 



The most remarkable accidental introduction to Southampton Water in southern 

 England was Mereenaria mereenaria. The species has undoubtedly responded to 

 locally warmer conditions in heated effluents of power stations. A single 

 specimen was first recovered in 1957 by the author, and it has been recorded 

 in the area since 1956. Hard clam has so extensively colonized Southampton 

 Water that it is the dominant bivalve in many places and supports a 

 commercial fishery. American authorities say that spawning seldom occurs 

 below 24°C. Although in the U.S. gonads begin to grow again in fall 

 immediately after spawning, in Southampton no major growth of gonads recurs 

 until spring. Another difference is that in the Southampton area the 

 critical temp for spawning is about 18°C. At first in the area only certain 

 years appeared to be favorable for spawning. Such yrs were the warm yrs 

 1955 and 1959. Now some spawning occurs every year, although only some yrs 

 are really successful. It is not known when the species was introduced into 

 Southampton Water. Clams taken from 1957 onward appeared to be relatively 

 old, perhaps dating from the 1930s. Some evidence has been found that a few 

 clams were introduced about 1926. Warm effluent appears to have facilitated 

 survival and reproduction. Density of clams is high. In one area 100 clams/ 

 m2 have been counted. In the Marchwood power plant outfall up to 16 clams/m' 

 are reported. Densities of young have been as high as 4,750/m2. Carriker 

 (1961) cited 3 clams/m2 as reasonable for commercial harvest. M. mereenaria 

 occurs in stone and shell gravel with mud, soft mud, and hard gravel and sand 

 in Southampton Water , and is described as remarkably unselective of substrate. 

 Growth differs in different locations, and in general is less than in the U.S. 

 They do best in the warm outfall. Most growth is in June-August. First 

 spawning may be as early as May in the warmer water. Successful setting 

 depends on adequate temp. Two peaks of larvae usually are observed, in 

 May- June and July-August. The first probably comes from warm effluent, the 

 second from summer spawning elsewhere, when temps are high enough. - J.L.M. 



1529 



Raytheon Company. 1972. 



An ecological survey of the Arthur Kill. Raytheon Co., Environmental System 

 Center, Environmental Research Lab. (unpublished? - or does n.p. mean no 

 pagination? ) 



Interlibrary loan could not trace this. Raytheon Company denies existence of 

 an environmental laboratory within their system. Search terminated. - J.L.M. 



1530 



Read, Kenneth R. K. 1966. 



Molluscan hemoglobin and myoglobin. I_n Physiology of Mollusca. Karl M. 

 Wilbur and C. M. Yonge (eds.) . Academic Press, New York, Vol. II: 209-232. 



Contains references to Mereenaria (Venus) mereenaria abstracted elsewhere in 

 this bibliography. - J.L.M. 



1531 



Reese, A. M. 1942. 



The old star-fish clam question. Science, N.S. 96: 513-515. 



Assumed that a toxic secretion, liberated by sea star and introduced between 

 valves of the clam, is responsible for opening the clam. - from Burnett, 

 Ecology 41(3), 1960 - J.L.M. 



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