Figure E- 



Frequency histograms of density (no./m-) at age for selected unionid species from Sylvan 

 Slough (RM 485.8) in Reach 15 of the Upper Mississippi River, 1994-95. Unionidswere 

 collected from 116 quantitative samples covering a surface area of 34 m-. 



9 11 



Estimated Age (years) 



13 15 17 19 21 23 25 27 29 31 33 35 



|ji-_ 



nmm 



Amblema pUcata 

 x=33/ni^ 



nnnn^nnnn^nnn^;.;.m. 



^rir^nmli 



Megalonaias nervosa 



x=2.2/m^ 



nfl "n n, 



JIO 



Quadrula quadrula 

 x=1.9/m^ 



nnnni lOn^i' 



Mr-. r-, Fl 



.^nll 







Quadrula metane\'ra 

 x=4.4/m^ 



I In! I[ I Irln7nn r-n^ _ ^ 



Quadrula pustulosa 

 x=14.2/m^ 



On 



HRr 



hD 



ElUpsaria lineolata 

 x=6.8/m^ 



n nn Hnn, 



n 



Obliquaria reflexa 

 x=3.9/m^ 



on 



HL 



3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 

 Estimated Age (years) 



Page E-3 



Whitnev et al , Unionid Sun-ev - Reach 1 5 UMR 



