16-2 of this study indicate that at lower temperatures the differences in size 

 between early-fed and starved larvae was not great even three weeks after 

 hatching. At higher temperatures both the rate of weight loss in starved 

 populations, and the rate of weight gain in early fed populations increased 

 markedly, with the major effect being seen on the rate of individuals in groups 

 which were fed an unrestricted ration shortly after yolk absorption. 



There are vast differences between the conditions that exist in the 

 laboratory and those in the natural habitat of the striped bass. These 

 differences Hmit, to some extent, use of laboratory observations as an aid in 

 interpreting conditions in the field. In these studies the only measurable 

 mortality was that most closely associated with the availability of food. Losses 

 due to predation, probably the most important sources of mortahty in nature 

 (5), were not involved at all here. It has frequently been suggested that the 

 most likely victims of predation in nature might be individual larvae that have 

 been weakened by the effects of starvation (5,11,15). 



Experimental groups in this study which received food were fed to excess. 

 Therefore, the difference in growth attainment between starved and fed groups 

 was probably at a maximum. Under conditions of restricted prey density, even 

 larvae fed early in development might not have enjoyed as great a growth rate. 

 At the same time, satisfactory food is probably never totally absent in nature 

 as it was among the starved groups in this study. 



Anemia nauplii are a frequently used laboratory diet for the larvae of fish 

 species that appear to require live food. Although Artemia nauplii appear to 

 support a satisfactory rate of growth in laboratory populations, there is little 

 nutritional information available to serve as a basis for comparison between 

 Artemia and the variety of micro-crustacea that comprise the natural food of 

 striped bass larvae (27). 



In nature, striped bass larvae are present on their estuarine nursery grounds 

 during the spring under conditions of rapidly rising water temperatures. An 

 average temperature rise of l^C per week is typical in the Hudson River 

 estuary during the period of larval striped bass abundance (36). Constant 

 temperatures were used in these laboratory studies. 



With these reservations in mind, some statements may still be made about 

 the probable early growth pattern of striped bass larvae under natural 

 conditions. Data presented here indicate that the size and developmental stage 

 of early striped bass larvae of a given chronological age are intimately related to 

 their thermal and nutritional history. In well studied estuaries, the probable 

 temperature history of a group of larvae spavmed at a particular time and 

 location may be estimated with some accuracy. However, a basis for 



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