Shocking and Picking of Brook Trout Eggs at Dry Mills State Fish Hatchery скачать в хорошем качестве

Shocking and Picking of Brook Trout Eggs at Dry Mills State Fish Hatchery

When hatchery staff check on the jars of incubating brook trout eggs and thousands of tiny eyes look right back, they’re ready for phase two of the fish rearing process! After several weeks incubating in jars, fertilized eggs and are now eyed-up and ready for shocking and picking. Survival of eggs is significantly higher in a hatchery setting than in the wild, but it’s not 100 percent. Dead eggs are problematic for viable eggs because they grow fungus that can be harmful to the remaining healthy eggs. Shocking and picking are steps taken to reduce this risk and protect viable eggs. Eggs are shocked by simply dropping them from 2-3 feet into a bucket of water. This is enough to knock out any weak eggs. Eggs are returned to incubation jars where any non-viable eggs will become light and clouded over the next 24 hours. This is important because it distinguishes them from the translucent orange healthy eggs. Eggs are then sorted using an egg picker, a process that used to be painstakingly done by hand. Eggs are picked up by a rotating wheel, and light is used to determine if the egg is viable or not. Light passes through healthy eggs but is reflected off the dead eggs. A puff of air gently shoots healthy eggs one direction and dead eggs another. Once the eggs are sorted, healthy eggs are moved to trays where they will remain for the next several weeks until they hatch. Hatchery staff will meticulously weed out dead eggs by hand to protect the healthiest eggs every day using siphons.