330 



Fishery Bulletin 88(2), 1990 



SUMMER WINTER 



DISTANCE OFFSHORE (n. miles) 



10 50 40 30 20 



n 



Figure 7 



Summer (January 1978) and winter (August 1977) sections of temperature, microplankton, anil elilorophyll-u values along line 16 

 in the vicinity of Lambert's Bav. South Africa. 



of the front as well as close inshore, and high levels 

 of chlorophyll-a were found inshore near the surface, 

 declining in concentration and following the isotherms 

 into deeper water in the vicinity of the front. Offshore 

 of the front, both chlorophyll-*/ and microplankton 

 levels were negligible. A similar pattern was noted in 

 a transect of the front off Cape Columbine in December 



1984, with copepod nauplii and copepodites concen- 

 trated in the front and chlorophyll-*; values increasing 

 towards the coast, inshore of the front (Armstrong et 

 al. 1987). Although the front may persist as a subsur- 

 face feature in winter, even during prevalent downwell- 

 ing conditions, it is much weaker as a consequence of 

 cooler water offshore. Microplankton and chlorophyll-a 



