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 limit, 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 mortality 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. 
Artemia 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 1°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 spawned at a particular time and 
location may be estimated with some accuracy. However, a basis for 
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