UJ 



6.0- 



w 



UJ 



o 

 o 



5.0- 



4.0- 



3.0 



[J ' 'A 1 ' 7 ' 'o' ' P ' 'A' ' 'J 1 ' 'o' ' |J' ' 'A 1 ' 'j' ' '0 1 ' |J' ' 'A 1 ' 'J 1 ' 1 ' 

 1970 1971 1972 1973 



3.0 | i i , A i i .j. , lQl i jji i i a i i iji i i . i |ji i i a i i iji i b . . jji" i 'i a i i iji i 

 1974 1975 1976 1977 



Figure 3.— Abundance of phytoplankton in the lower Sheepscot River estuary: A) 1969-73; B) January 

 1974-June 1974 and at station D7, July 1974-August 1977. 



Table 2.— Reported spawning temperatures and periods of Mytilus edulis. 



Spawning in response to lunar cycles is also a 

 possibility. Korringa (1947) noted that the European 

 oyster, Ostrea edulis, spawns around the period of 



spring tides and attributed this to increased hydro- 

 static pressure. Chipperfield (1953) also observed 0. 

 edulis at several sites in Great Britain shortly after 



999 



