CONTENTS 



Page 



Introduction 1 



Materials and methods 1 



Laboratory ^ 



Orifices 2 



Hydraulics 2 



Test procedure 4 



Experimental design 5 



Response of salmonids to orifice conditions 5 



Test condition 1--Deep horizontal orifice vs. deep vertical orifice . 5 



Test condition 2- -Shallow horizontal orifice vs. shallow vertical 



orifice 6 



Test condition 3--Shallow horizontal orifice vs. deep horizontal 



orifice 6 



Test condition 4--Shallow vertical orifice vs. deep vertical orifice . 6 



Lateral orientation of fish in the experimental system 6 



Interpretation 7 



Summary and conclusions 8 



Literature cited , 8 



