16* 



15* 



14* H 



13* 



12* 



11* 



10* 



9* 



8* 



7* 



6* 



5* 



4* 



3* 



2* 



1* 



0* 



MUSSEL MORTALITY 



RECAPTURED AMBLEMA PLICATA 



DOWNSTRM 



GROUNDED 



PILINGS 



Note 



Numbers at the top of bars indicate the total number of 

 marked Amblema plicata recaptured at the plot in 1984. 



DOWNSTRM = unfleeted plot, downstream control 



GROUNDED = fleeted plot, barges against shore 



PILINGS = fleeted plot, barges tied to pilings 



Figure 9. Mortality rates for Amblema plicata recaptured from 

 fleeted and unfleeted plots in the Illinois River at 

 Naples. 



36 



