standard and total lengths were compared on all measured bass taken from Sports- 

 men's Lake to learn whether the ratio of total length to standard length Is constant. 

 The ratio was found to change as shown In table 8. It may be seen that the body grows 

 In length more rapidly than the tall.* 



It was possible to determine the ages of all but two of the bass taken following 

 the first poisoning. The numbers of bass of known ages are shown dlagramatlcally by age 

 groups In the shaded areas of fig. 5. The two bass of undetermined ages from the first 

 poisoning and 21 bass from the second poisoning were arbitrarily assigned to age groups 

 on the basis of size and are shown in unshaded areas In fig. 5. 



Spawning and survival must have been more successful In some years than In others. 

 As may be expected, the greatest numbers of bass were one- and two-year-olds. But, 

 there were more fish in the five- and six-year groups than In the three- and four -year 

 groups. This fact may Indicate an abundance cycle with dominant broods appearing every 

 three or four years. Eschmeyer** presents evidence of dominant broods among the bass 



TABLE 8.— RATIO OF TOTAL LENGTHS TO STANDARD 

 LENGTHS IN BASS OF DIFFERENT SIZES. 



which he poisoned in Howe Lake, Michigan. In his case the first summer and fourth sum- 

 mer fish were much more numerous than bass of other ages. 



Age determinations were made from the scales, distances between annull were meas- 

 ured and the length of each fish at the end of each year of life was calculated In the 

 usual manner. Table 9 shows the average of these calculated lengths for each year's 

 spawn. Table 10 shows the average yearly length Increases of the fish shown In table 9. 



Curves showing the sum of the length increases and the average lengths of these 

 bass are given in fig. 6. The sum of the length Increases (solid line) gives. In most 

 respects, a more nearly true picture of the growth history of these bass. Average 

 length curves are subject to greater irregularities. For example, the nine-year old 

 fish average slightly shorter than the eight -year old fish. This does not mean that 

 bass shrink between their eighth and ninth years but that the eight-year old average 

 includes two unusually large fish which are not represented in the nine-year average. 



No significant differences in growth rates of the two sexes could be found. 



Scales and measurements from nine largemouth bass taken by anglers from Lincoln 

 Lakes during 1937 and 1938 show a rate of growth similar to that of the poisoned bass 

 of Sportsmen's Lake. 



* Bennett found no change in the ratio of total to standard length in smallmouth bass 

 when the former was measured from the tip of the snout to a line across the end of 

 the tail spread in the natural position. Bennett, G. W. 1938. Growth of the Small- 

 mouth Black Bass, Micropterus dolomieu Lacepede, in Wisconsin Waters. Copela, No, 

 4, pp. 157-70. 



»* Eschmeyer, R. W. 1938. The Significance of Fish Population Studies in Lake Manage- 

 ment. Trans. Third N. Am. Wildlife Gonf., pp. 458-68. 



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