142 



American Fisheries Society. 



leading to complete knowledge of the relations which the 

 species bear to each other and to the environment and ap- 

 plication through the knowledge thus gained of the principles 

 which mankind has applied through the ages in securing and 

 maintaining his own supremacy. 



III. 

 Potential and Mortality Table for Small-Mouth Bass. 



Assume a lake where scarcity of food, low temperature, or other en- 

 vironmental reasons defer spawning until the fish are three years old. If 

 spawning starts sooner the proportion reaching maturity and reproduction is 

 less than .000269 since the total number per year is one thousand, tinless 

 all die under six years of age, which is unlikely. 



Mortality before spawning probably substantially correct. Mortality 

 after first spawning purely hypothetical. 



For many years it has been increasingly evident to those who 

 have consulted old records, or otherwise kept in touch, that the 

 supply of our native game fishes, particularly in the more de- 

 veloped parts of the country, has been steadily decreasing. The 

 fact that this diminution has not attracted the full and respon- 

 sive attention which it merits is probably due to a number of 



