Figure G-2. Growth curves based on the average observed size at age (Table G-6) ofMegalotiaias nen'osa 

 collected from Reach 15 of the Upper Mississippi River in (a) 1994-95 and (b) 1987. All 

 growth curves were best described by a polynomial regression formula (Table G^). 

 Coefficient of determination (r-) values for each growth curve are listed. Minimum commercial*" 

 shell height (Illinois) and average age at sexual maturity (Table G-2) are also shown. 



5 = 



8 12 16 20 24 28 32 36 



Estimated age (yrs.) 



160 



140 



120 



100 



80 



60 



40 



20 







12 16 20 24 



Estimated age (yrs.) 



Page G-24 



Whitney et al., Unionid Sunev - Reach 15 UMR 



28 



32 



36 



