spawnin<»: i)eri()(l also are difficult to 

 hold in ])()nds or .streams without 

 mortality, but experience with these 

 species has not b?en so extensive as 

 with the chiuooks. (uMierally arti- 

 ficial spawniiit:' of" silver salmon 

 takes place neai- the spawnina- areas. 

 and the red salmon are tiap[)ed and 

 spawned as they ascend streams 

 from lakes to spawn. Steelhead 

 trout adults, too, wlien trapped 

 along with salmon in the fall, are 

 difficult to hold over the winter for 

 spring spawning. 



Studies by the Washington De- 

 partment of Fisheries have shown 

 that silver-sahnon young should be 

 reared in the hatchery ponds mitil 

 their second spring and then re- 

 leased. The same appears true of 

 steelheacl-trout young. Yearling 

 red-sahnon fingerlings have pro- 

 duced excellent returns when re- 

 leased into their "home" lake in the 

 fall of the year. 



Chum salmon usually are almost 

 mature sexually when they enter 

 fresh water, and the adults can be 

 readily trapped and spawned. 

 Under natural conditions the young 

 fish proceed to salt water immedi- 

 ately after emergence from the 

 gravel, and the usual hatchery prac- 

 tice is to release the young fish at 

 that time. 



The fall chinook salmon is the 

 species most extensively propagated 

 at most of the salmon hatcheries. 

 It is probably the easiest to secure 

 and handle in the hatchery. Fur- 

 thermore, the fall chinook is native 

 to the lower reaches of the water- 

 sheds, and therefore usually below 

 major dams, and can be maintained 

 and developed most readily. There 



is economic justification, too, for 

 concentration upon the propagation 

 of fall chinook in those areas wiiere 

 mamnade conditions req.uire the 

 assistance of the hatchery for 

 the maintenance of the salmon re- 

 source. All of the species require 

 about the same capital and annual 

 investment for hatchery production 

 to secure like returns in numbers of 

 adult fish, but the fall chinook, at- 

 tains the greatest adult size and 

 thus contributes more pounds of fish 

 per dollar invested. 



The following descriptions of 

 methods, procedures, and equipment 

 are of those generally employed in 

 the propagation of fall chinook 

 salmon. The few deviations from 

 this pattern to propagate other spe- 

 cies will be noted if pertinent. 



Spawn taking 



Wlien a group of adults is avail- 

 able in the racked stream area or in 

 the holding pond, and the majority 

 are mature, the fish are brought to- 

 gether in a small area for sorting 

 and spawning. The usual spawn- 

 ing run consists of both sexes in 

 about a 50-50 ratio. 



Experienced men sort the salmon, 

 placing males and ripe females in 

 separate enclosures. Jacks or pre- 

 cocious males, as well as surplus 

 males, are killed. Green females 

 are returned to the pond for further 

 maturation. 



The indication of ripeness in the 

 female is the separation of the eggs 

 in the ovaries, but it is not usually 

 possible to determine this by an ex- 

 terior examination. Experienced 

 spawntakers rely mainly upon the 

 general appearance of the female 



25 



