Salmon Freshwater Habitat
Trout and salmon need cold water to survive and grow. Rain, and snow melting from mountain peaks feed their stream and lake habitats. Healthy salmonid streams are usually shaded by trees. The tree roots make the stream banks stable and provide hiding places for the fish. Leaves from the trees fall into the stream and become food for insects, which are in turn eaten by salmon and trout.
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This section of the Shasta River provides good salmon and steelhead habitat. Trees shade the water and keep banks stable. It may also provide suitable spawning gravel. | |
Insects such as stoneflies, mayflies and caddisflies spend their early life stages as nymphs in the gravel riverbed. When mature, they swim to the water surface and then fly away to reproduce. Fish eat both the nymphs and adults. | Photo by T. Roelofs |
As young salmon and trout grow larger, they move from shallow areas into deep pools. Pools are scoured when water plunges over or around boulders and logs. The "bubble curtain" is a favorite place for salmon and trout. They can't be seen by predators above and there is plenty of oxygen. The current brings insects and other small food items. At the end of pools, where the stream narrows, the current picks up and washes the gravels clean, making them ideal for nests | |
This fry can dart under rocks and hide beneath the white "bubble curtain" made by the broken water surface. Good cover is important for the survival of salmon and trout. They are favored food for birds, amphibians and other fish. | |
Some salmon and trout spend their lives in lakes, constantly moving about to find food. The surface of lakes may freeze in winter and the water underneath becomes quite cold. After spring thaw, salmonids feed around the edges of lakes. As the lake surface warms in summer, they retreat to the cold depths. They eat small animals called plankton, and insects that alight on the surface of the lake. As trout grow larger in lake environments, they often feed on small fish, such as minnows or even smaller trout. |
Salmon and Steelhead Life Cycle: | Early Stages | Adult | Spawning |
Salmon and Steelhead Habitats: | Freshwater | Ocean |
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