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Bring on the alevin stage!

This morning we were greeted by about 1,000 wiggling chinook salmon alevins in both classroom incubators combined. Over the weekend all of our eggs hatched. When the eggs hatch, it is common to find a white frothy foam on the surface of the water and to have the water a bit cloudy. This is caused by the egg yolk residue mixing with the water. As a result, the ammonia level in the incubators usually climbs to dangerous toxic levels. To remedy this, we change out half or more of the water to dilute the ammonia. The incubators also are equipped with ammonia filters, but it often isn’t enough to keep the level down once they hatch. You will notice the alevins have very large yolk sacs. These are the food sources for the young salmon until the sacs become used up and the fish become free-swimming fry. Stay tuned for more updates!