October 14, 2021, by admin

We are all shocked its fall already, even the eggs! It’s a sad fact that not every egg that is taken during spawning will be successfully fertilized and eventually hatch. These “dead” eggs will grow fungus and can be harmful to the remaining viable eggs if left comingled. The process to remove these dead eggs is called shocking and picking. After the eggs have passed their most delicate stage, directly after fertilization, we shock them by dropping the eggs at a specified height onto a metal surface and then set them aside for 24-48 hours. The shocking isn’t damaging as any viable eggs will bounce unharmed. Unfertilized eggs, however, will break their yolk sacks and become scrambled eggs. After at the waiting period, the eggs with broken yolk sacks will turn opaque white and can then be easily sorted out from the viable eggs. All eggs are run through an egg picker which uses light reflections to sort the eggs; light will pass through good eggs whereas light will bounce back after hitting the opaque dead eggs. The picker will use puffs of air to separate each grouping. Weights from each set of dead or alive eggs can be used to determine survivorship through this stage. We generally can achieve a 95% survivorship throughout this stage as opposed to the 3%-5% range in the wild. Fall is an exciting time when we in the hatchery begin to see the successes from all our hard work spawning!