conditions. A basis for estimating spatial require- 

 ments is provided bj' data (table 2) from a series 

 of capacity experiments in 1957. In these experi- 

 ments large numbers of fish were collected over a 

 48-hour period and then released in a 1-hour test. 

 During one such experiment, fish averaging 9.2 

 pounds in weight were passed through a l-on-16- 

 slope fishway (a fishway that rises 1 foot for every 

 16 feet of fishway length) only 4 feet wide (fig. 7) 

 at a rate of 3,000 fish per hour without any indica- 

 tion that capacity had been reached. Experi- 

 ments in the Washington-shore fishway at 

 Bonneville examining possible effects of the 

 collection-and-release technique upon fish per- 

 formance, although not yet completed, appear 

 to confirm the laboratory data shown. 



"if- »ak "K I 





HL^t: 



t^ ijy.^ 



Figure 9. — The two endless (ishways, 1-on-16 slope 

 on leFt and 1-on-8 slope on right. Observers 

 along walkways record progress of fish in the re- 

 spective fish ways. 



r 



Diffusion Chamber 

 Entronce Frshwoy 



Entry Chonnel (elewSO') 



To Exit Fishwoy 



- Direction Fish Moves 



l-on-l6 l-on-8 

 Slope Slope 



__-— By-poss Channel (elev 50) 



-Spillout 



- Fistiwoy Enfry Gofes 



-introductory Pool Gate 

 ■ Releose Compartment 

 " Introductory Pool 

 "Collection Pool 



Figure 10. — Plan view oF the 1-on-16- and 1-on-8- 

 slope endless Fishwo/s with auxiliary approach chan- 

 nels and pools. 



Tabic 2. — Observed space utilization in two fishway capacity 

 tests, 1957 



J StT Appendix A. 



