Atlantic Salmon
Pictures

Atlantic salmon develop a silver-blue sheen with black spots above the lateral line when they go to sea to mature

Male Atlantic salmon turn slightly green and have black spots when they're ready to spawn

Young salmon are called smolts after they turn silvery and migrate to the ocean

Atlantic salmon are fusiform, which means that they have a spindle-like shape

Salmon and steelhead face a challenging 900-mile swim through a series of dams before they can reach their spawning grounds in Idaho and Wyoming.