Body Shape Generally fish are "torpedo shaped" with rounded nose, a thicker middle and a tapered tail. The shape of the fishes body is very important to how it swims. Fish with round bodies are good swimmers; fish with shorter bodies can turn quickly.

The Head of the fish has its mouth, nostrils and gill cover. The gills (found under the gill covers) allow the fish to breath. As water moves over the surface of the gills oxygen is absorbed - like lungs in land creatures.

Scales protect the fish from its environment. They overlap like shingles on a roof so that the skin of the fish is not exposed. As a fish grows, their scales produce "rings" much like a tree - and that is one way scientists can tell how old a fish is. Most fish get extra protection from a layer of slime that covers their scales. This slime helps them move through the water better, and keeps pests off of the fish skin.

The Lateral Line is how the fish "hears". It is sensitive to pressure, vibration, movement and sound and lets the fish know what is in the water around them.

The Fins help the fish swim. The large muscles of the body actually do most of the work, but the fins help with balance and turning. In some fish the fins are large and spiney and help protect the fish from its predators who do not want a mouthful of sharp spears!

Some Fish of the Northwest