1. Recruitmeat to the Blue gill Catch . 



Length-frequency distributions of the bluegill catches during each 

 netting period are shown in Figure 8, All bluegills caught during Period 

 I were 5.2 inches long or longer. A^;e determinations from s cales collected 

 during the netting indicates that these fish were probably all of the 19U5 

 or older year classes ; that is of the "residual population". 



Table 8 lists the relative numbers of "recruited" fish (19i;6 and 

 younger year class) and "residual" fish (19U5 and older year class) in the 

 catch during each netting period. These data are presented graphically in 

 Figure 9. 



Recruitment began during Period II when a few fish of the 19U6 year 

 class appeared briefly in the catch. Dxiring Period IV, more of these 2- 

 year-old fish were caught, and in Period V they made up 8l percent of the 

 total number of fish caught. Additional recruitment from the 19U6 year 

 classes together with the 19ii7 year classes continued until September. 

 During September 92 percent of the bluegills being caught were "recruited" 

 fish that had not been available at the beginning of netting in May. 



Like the 2-year-old black crappies and white crappies, the 2-year-old 

 bluegills were large enough to have been caught during May and June had 

 they been available, then. Their sudden appearance in quantity during 

 July suggests that they were not associated with the older bluegills dur- 

 ing the early part of the season. Since these younger fish first appeared 

 at stations closest to the main river channel, it may be that during early 

 spring they were in the deeper waters of the river. The recruitment of 

 the I9U7 year class seems to coincide with their growth to catchable 

 size. 



2. Losses from the Bluegill Population . 



As with the black aid the white crappie, there is evidence of a high 

 loss among older bluegills during the summer, (Figure 8). During Period 

 I, 17 percent of the catch (all 3, h and 5-year-old fish) was made up of 

 h and 5-year old fish. By Period IX, these two oldest age groups had 

 disappeared from the catch entirely. 



The trap net set in previously unnetted Broken Arrow Slough during 

 Period IX took no bluegills large enough to be considered h or 5-year- 

 old fish (Figure 6) . From this evidence it appears likely that the re- 

 moval of bluegills during the summer's netting at the regular stations 

 had little effect upon the length-frequency of the catch. 



No migration of bluegills was noted dxiring the summer, and it is 

 probable that most of the losses of the older bluegills during this 

 period was due to natural mortality » 



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