The Atlantic salmon, vulnerable to many stressors and threats including habitat degradation, is considered an indicator species-its health reflects the health of its ecosystem. The plants then pass along the nutrients to the many animals that live and thrive in the region. As the salmon spawn and begin to die, their carcasses decompose and fertilize the soil of the river banks and boreal forests of the park. The sockeye salmon, for example, is a keystone species in Alaska’s Bristol Bay, which is part of Katmai National Park. Some species of salmon are considered keystone species-vital to sustaining their ecosystems. Ten to 40 percent of female Atlantic salmon, however, survive and return to the sea. Pacific salmon die within a few weeks of spawning, as do most male Atlantic salmon. This perilous, exhausting journey, sometimes hundreds of miles long against the current, is called a “salmon run.” Salmon use smell to navigate back to their original spawning grounds. Sockeye salmon stay for up to three years in their natal habitat-longer than any other salmon.Īdult salmon typically spend one to five years in the ocean, where they feed mainly on zooplankton, before returning to freshwater streams to spawn. All species are born in freshwater streams and migrate to the ocean as juveniles. Salmon are known for their grueling migrations. and Canadian Pacific Northwest, as well as in Japan. Pacific salmon species are found throughout the western U.S. In addition to the small North American population, groups of Atlantic salmon are also found in coastal rivers of northeastern Europe, including Iceland and northwestern Russia. today, Atlantic salmon are found only in a handful of rivers in Maine. and Canada, but overfishing and habitat destruction following European settlement dramatically reduced their numbers. HabitatĪtlantic salmon were once abundant throughout the North Atlantic coast off the U.S.
Many species of salmon are considered keystone species-vital to the health of their ecosystem. (Here are some tips to make sure you’re buying sustainable salmon.) The Atlantic salmon was nearly fished to extinction-the commercial market is now almost exclusively farm-raised fish. Wild salmon is fished extensively for food, both recreationally and commercially.
The seven species of Pacific salmon typically range in length from a foot and a half to two and a half feet. Male sockeye salmon develop humps on their backs. Pacific salmon undergo significant transformations when returning to freshwater from the ocean: Some species go from silver to a deep maroon others turn a deep black. Atlantic salmon are the largest salmon species, typically growing to just under four feet in length. When they migrate to the ocean, they turn silvery. While in freshwater, Atlantic salmon are brown and spotted.
Salmons have sleek, streamlined bodies that typically change color throughout their lifetimes. They’re found in tributaries of the Pacific and Atlantic Oceans, and most species are anadromous: They are born in streams and rivers, migrate out to the open sea, and then return to freshwater again to reproduce. Salmons include seven species of Pacific salmon and one species of Atlantic salmon.
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