User talk:Mike Cline/Articles Under Contemplation/Steelhead rewrites

Taxonomy
The scientific name of the steelhead is Oncorhynchus mykiss. The species was originally named by German naturalist and taxonomist Johann Julius Walbaum in 1792 based on type specimens from the Kamchatka Peninsula in Siberia. Walbaum's original species name, mykiss, was derived from the local Kamchatkan name used for the fish, mykizha. The name of the genus is from the Greek onkos ("hook") and rynchos ("nose"), in reference to the hooked jaws of males in the mating season (the "kype").

Sir John Richardson, a Scottish naturalist, named a specimen of this species Salmo gairdneri in 1836 to honor Meredith Gairdner, a Hudson's Bay Company surgeon at Fort Vancouver on the Columbia River who provided Richardson with specimens. In 1855, William P. Gibbons, the curator of Geology and Mineralogy at the California Academy of Sciences, found a population and named it Salmo iridia (Latin: rainbow), later corrected to Salmo irideus. These names faded once it was determined that Walbaum's description of type specimens was conspecific and therefore had precedence. In 1989, morphological and genetic studies indicated that trout of the Pacific Basin were genetically closer to Pacific salmon (Oncorhynchus species) than to the Salmos – brown trout (Salmo trutta) or Atlantic salmon (Salmo salar) of the Atlantic Basin. Thus, in 1989, taxonomic authorities moved the rainbow, cutthroat, and other Pacific Basin trout into the genus Oncorhynchus. Walbaum's name had precedence, so the species name Oncorhynchus mykiss became the scientific name of the rainbow trout. The previous species names irideus and gairdneri were adopted as subspecies names for the coastal rainbow and Columbia River redband trout, respectively. Anadromous forms of the coastal rainbow trout (O. m. irideus) or Columbia River redband trout (O. m. gairdneri) are commonly known as steelhead.

Subspecies
Subspecies of Oncorhynchus mykiss known as steelhead are listed below as described by fisheries biologist Robert J. Behnke (2002).

Range
The native range of Oncorhynchus mykiss is in the coastal waters and tributary streams of the Pacific basin, from the Kamchatka Peninsula in Russia, east along the Aleutian Islands, throughout southwest Alaska, the Pacific coast of British Columbia and southeast Alaska, and south along the west coast of the U.S. to northern Mexico. The range of coastal rainbow trout (O. m. irideus) extends north from the Pacific basin into tributaries of the Bering Sea in northwest Alaska, while forms of the Columbia River redband trout (O. m. gairdneri) extend east into the upper Mackenzie River and Peace River watersheds in British Columbia and Alberta, Canada, which eventually drain into the Beaufort Sea, part of the Arctic Ocean. Since 1875, the rainbow trout has been widely introduced into suitable lacustrine and riverine environments throughout the United States and around the world. Many of these introductions have established wild, self-sustaining populations.

Conservation status


Steelhead populations in parts of its native range have declined due to a variety of human and natural causes. While populations in Alaska and along the British Columbia coast are considered healthy, populations in Kamchatka and some populations along the U.S. West Coast are in decline. The U.S. National Marine Fisheries Service has 15 identified distinct population segments, in Washington, Oregon, and California. Eleven of these populations are listed under the U.S. Endangered Species Act, ten as threatened and one as endangered. One distinct population segment on the Oregon coast is designated a U.S. Species of Concern.

The Southern California distinct population segment, which was listed as endangered in 2011, has been affected by habitat loss due to dams, confinement of streams in concrete channels, water pollution, groundwater pumping, urban heat island effects, and other byproducts of urbanization. Steelhead in the Kamchatka Peninsula are threatened by over-harvest, particularly from poaching and potential development, and are listed in the Red Data Book of Russia that documents rare and endangered species.