Growth 79 



Condition and Growth Rate 



Higli condition of fishes is usually associated with rapid growth, but 

 this is not always so, particularly where fish are living in very soft water 

 in which there may be such a shortage of calcium as to curtail the 

 growth of the fishes' skeleton. In some other locations, relatively rapid 

 growth seems to be associated with moderately low condition, at least 

 during a part of a year. 



Use of Condition in Management 



An important value of condition factors is in their use in determining 

 the well-being of a fish population in w^hich one has a special interest, 

 either as a sport fisherman or as a lake owner. Often, when fish are in 

 poor condition (exclusive of lows of normal cycles), it may mean over- 

 population or disease. A high condition may mean a sparse population or 

 a high temporary food supply. When either of the extremes of condition 

 may appear, the situation may bear investigation. 



The condition of any component of a population of fishes is related to 

 the relative abundance of food for that group, and this relative abundance 

 of food may be related to high natural food production of the aquatic 

 habitat; but more especially to the number of individuals among which 

 a specific quantity of food must be divided. Thus, rapid growth, high 

 condition, and large average size of a species may be essentially a function 

 of natural or artificial cropping, because the type and intensity of cropping 

 that occurs may determine the amount of food an individual fish is able 

 to gather in a given period of time. 



Average condition figures have been calculated for most species of 

 fresh-water fishes of interest to anglers. ^-^ These condition figures may be 

 used by lake and pond owners as well as fishery biologists as a basis for 

 comparison with the condition of fish that are members of a local popula- 

 tion. 



GROWTH 



Although a new-born Great Dane or Chihuahua pup may be expected 

 to grow to a rather definite size within a period of about a year and then 

 remain the same size throughout the rest of its life, no amount of whole- 

 some food would cause a Chihuahua to approach the size of a Great 

 Dane, nor would a severe shortage of food prevent a Great Dane pup from 

 greatly exceeding the size of a mature Chihuahua in the one-year period. 



However, growth in fishes is unlike growth in most warm-blooded 

 animals in that it is relatively indeterminate and follows no exact pattern 

 of attaining a maximum size in relation to a specific length of time. Thus, 



