INTRODUCTION 



BY Harden F. Taylor 

 Executive Director of the Survey 



The purpose of Part II of this Survey is to assemble and summarize the 

 present knowledge of the natural history of the several economic species of 

 fish and shellfish and also game fishes in North Carolina waters, and to focus 

 attention on the large unknown area where further research is needed. In 

 carrying out this purpose, the broad subject has been subdivided and as- 

 signed in its parts to biologists who are considered qualified to deal with 

 them. 



In addition to the detailed treatment of the fisheries by species, the ecology 

 and dynamics of the flora and fauna of the region as a whole ought also to 

 be considered at length, but in the absence of sufficient exact knowledge to 

 make such a treatment worth while, we can here mention only a few gen- 

 eralizations and must leave the rest to future research. 



The lay of the land (and water) of the coastal region of North Carolina, 

 as dealt with in detail in Part I of this Survey, predetermines the kind and 

 amount of living things to be found there. 



The outer banks enclose the mouths of the rivers to form sounds; the 

 input of the rivers into these sounds varies greatly in quantity, turbidity, 

 and chemical content with rainfall and run-off from the land, and varies also 

 in temperature with the inland weather and the seasons. The sounds them- 

 selves are shallow with much surface in proportion to volume, and can change 

 in temperature much and quickly. Their salinity or saltiness is governed by 

 the back-flow of sea water through the inlets as affected by tide and the 

 direction and velocity of wind. Moreover, precipitation into and evaporation 

 from the sounds affect both salinity and temperature of the water. The over- 

 all effect of these and other variables is to provide not constant but highly 

 variable conditions in both time and place in the sounds to which animals and 

 plants must accommodate themselves one way or another. Attached forms 

 such as seaweeds, grasses, and mollusks must be able to endure a wide variety 

 of conditions if they are to survive ; swimming forms can either endure these 

 conditions or migrate; some of them, such as crabs and flounders, are suffi- 

 ciently tolerant of salinity and temperature to remain in the sounds the year 

 round; most of the others migrate seasonally into the sounds in summer and 



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