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Native trout spawning

Each spring and fall our rainbow, brook and brown trout spawn on exhibit. The males develop a hooked jaw, or kype, with which he fights or drives off rival males with; they also become extremely colorful at this time. The male fans out a nest called a redd, then if he’s lucky a female will join him on the nest to mate. She deposits small (3-5mm) eggs and he fertilizes them with milt. Unfortunately, other trout feast on the eggs, devouring most of them before they can settle into the substrate to mature. Eventually the juvenile trout, or fry, will emerge from the eggs, use up their remaining yolk sac and become free-swimming fish. At this time they begin to eat small invertebrates, plankton, etc, but in our exhibit we start them on artificial feed as early as possible. As soon as they are large enough to not be eaten, we put them in the Mountain Stream exhibit http://www.thevlm.org/mountainstream.aspx which houses other juvenile trout with native darters, shiners, sculpin, and various others. After about 6 months they will return to the adult trout exhibit.