 This part of the stream is a riffle. Riffles are the shallower, faster moving sections of a stream. Look for areas with a fast current where rocks break the water surface. That's a riffle.
 Riffles are important to fish habitat. As water rushes over the rocks it adds oxygen to the water. Insects that live in the water need oxygen, so they like to live in the riffles. Fish can find food to eat in riffles.
 The rocks on the bottom of the stream are called "gravel." They are also important to fish habitat.
Streams with too much sediment covering the gravel are a big problem for fish. Fish lay their eggs in the gravel. If the gravel gets filled with sand or dirt, the eggs smother.
In a clear, clean stream as many as 60% of a fish's eggs will survive. Maybe only 5% will survive if there's sediment in the stream.
Take the Bait – What To Remember When Talking About Fish Habitat!
 - A good fish stream has "clean" gravel - there's no dirt between the rocks.
- Good fish habitats also have pools, insects, shade, aquatic plants and lots of plants on the banks.
- Sediment in the stream can cloud the water so fish can't see predators.
- Sediment also can clog fish gills and smother fish eggs.
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