BROODSTOCK, SPAWNING, AND EGG HANDLING 



133 



Figure 43. Wild northern pike broodstock are trapped for egg- taking purposes. 



the culturist must provide conditions as optimum as possible for such 

 things as pond management, disease control, water quality, and food sup- 

 ply. 



The salmonid fishes generally reduce their feeding activity prior to 

 spawning, and Pacific salmon discontinue feeding entirely during the 

 spawning run. Trout broodfish usually are fed formulated trout feeds in 

 quantities of 0.7-1.0% of body weight per day at water temperatures 

 averaging 48-53°F, and then fed ad libitum as spawning season approaches. 

 Food intake can drop as low as 0.3-0.4% of body weight per day during ad 

 libitum feeding, when the fish are fed high- protein diets containing 48-49% 

 protein and 1,560-1,600 kilocalories per pound of feed. 



In some cases, coolwater species are held at the hatchery and a domesti- 

 cated broodstock developed. Coolwater fishes all are predators and must be 

 provided with suitable forage organisms. There has been some recent suc- 

 cess in developing formulated diets that cool- and warmwater predators 

 will accept, and in developing new strains or hybrids of these species that 

 will accept formulated feeds. 



For predator species such as largemouth bass, providing a suitable food or- 

 ganism for growth and maintenance in the amount needed is very impor- 

 tant. The rapid growth and development of largemouth bass makes raising 



