493 



1 Marine Biological Laboratory 



LIBRARY 



APR 2 1 1965 



WOODS HOLE, MASS. 



SALMON ESCAPEMENTS ABOVE 

 ROCK ISLAND DAM, 1954-60 



by Robert R. French and Roy J. Wahle 



SPECIAL SQENTIFK REPORT-FISHERIES Na 493 



UNITED STATES DEPARTMENTjOFJ>j[E_ll^^ 



FISH AND WILDLIFE SERVICE 



