TEMPERATURE 



3 DEPTH(m) 



12 OEPTHCm.l 



TEMPERATURE 



II 

 13.0 12.0 



168 I6A 16 

 2J0 3 10 31.5 



8 DEPTH (m.) STATION 168 ISA 16 



12 Olio lOO 9.0 

 - - . 



TEMPERATURE 

 17 



le DEPTH (m.) 



Figure 6.~Inshore-offshore vertical profiles of temperature (°C.) and salinity (p.p.t.). 

 Gulf of Maine coastal waters, summer 1966. 



temperatures depressing the growth of crus- 

 tacean eggs and larvae (Fish and Johnson, 

 1937), and lack of appreciable influx of zoo- 

 plankton from the north and east (Bigelow, 

 19^6; Redfield, 1941) lead to minimal condi- 

 tions for population growth. In contrast, the 

 increased stability of the water column, and 

 higher spring and summer temperatures west- 

 ward provide an increasingly favorable 

 environment for growth and development of 

 zooplankton from Mt. Desert to Cape Ann 

 (Sherman, 1966). 



Circulation and Between- Year Differences in 

 Zooplankton 



The intensity and duration of river dis- 

 charge have a dominant influence on the annual 

 development of the nontidal drift in the Gulf 

 of Maine (Bigelow, 1927; Bum pus, I960; Bumpus 

 and Lauzier, 1965). Spring runoff for major 

 rivers emptying into the central and western 

 Gulf was higher in 1966 than in 1965 (table 6). 

 This increase was apparently responsible for 



