Salmons are found in tributaries of the Pacific and Atlantic Oceans. They are born in streams and rivers.

They migrate out to the open sea. Then they return to freshwater again to reproduce. Atlantic salmon are the largest salmon species. They typically grow to just under four feet. Adult salmon spend one to five years in the ocean. They feed mainly on zooplankton. Salmon use smell to get back to their original breeding grounds. Sockeye salmon is a keystone species in Alaska's Bristol Bay. It is part of Katmai National Park. When a river ecosystem is clean and well connected, its salmon population is typically healthy and robust. Atlantic Atlantic salmon, vulnerable to many stressors, is considered an indicator species. Atlantic fishing has been banned in the U. S. since the late 1940s. Today, all Atlantic salmon consumed in the United States is farmed. It was often imported from as far away as Chile, Scotland, and Norway. Environmental groups have compared salmon aquaculture facilities to floating pig farms. The survival of wild salmon is dependent on the preservation of suitable habitat for them to spawn and their offspring to grow. Historically, artificial damming, overfishing, and pollution have led to large declines in Atlantic salmon. In 2011, Atlantic salmon were listed as endangered in the US. .