Our sc’win (sockeye) alevins are almost all completely hatched. Once they hatch we add plastic rings bio-media (or synthetic media) to their incubation boxes, which mimics silt in the rivers. The newly hatched alevins (yolk sac fry) will burrow themselves into the silt for protection until they have utilized their yolk and can start feeding freely.
The alevin hide in the rings and can then utilize all their yolk for development. If we didn’t add the rings, they would constantly be swimming and they would use too much energy and therefore would not continue to develop properly. Once, the alevin have used almost all of their yolk sacs, they are ready to begin feeding.
To move them out to the rearing area, we utilize a unique “ponding” method. This method is called volitional release, and basically the fry swim out to their respective raceways for feeding all by themselves!!! No handling which reduces a lot of stress and mortality. Once they are in their raceway, we start the feeding process. We feed them all by hand, and around 8-10 times per day.