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Puget Sound salmon recovery is a collective effort of federal, state and local authorities and non-profit coalitions of universities, scientists, business and industry aimed at restoring Pacific salmon and anadromous forms of Pacific trout (''Oncorhynchus'') within the Puget Sound region. The Puget Sound lies within the native range of the Pacific Salmon (''Oncorhynchus'') and two sea-run forms of Pacific trout, the coastal rainbow trout (''O. mykiss irideus'') or steelhead and coastal cutthroat trout (''O. clarki clarki''). Populations of ''Oncorhynchus'' have seen significant declines since the middle of the 19th century due to over fishing, habitat loss, pollution and disease. Salmon species residing in or migrating through the Puget Sound to spawning streams include Chum (''O. keta''), Coho (''O. kisutch''), Chinook (''O. tshawytscha''), Sockeye (''O. nerka''), and Pink salmon (''O. gorbuscha''). Pacific salmon require freshwater rivers for spawning and most major tributaries of the Puget Sound have salmon, steelhead and cutthroat trout spawning runs. Major organizations involved in recovery efforts include the Puget Sound Partnership,〔(【引用サイトリンク】title=PugetSoundPartnership-Leading Puget Sound Recovery )〕 Shared Strategy for Puget Sound,〔(【引用サイトリンク】title=Puget Sound Communities Working Together to Create a Future for Both People and Salmon )〕 South Puget Sound Salmon Enhancement Group and Westsound Watersheds Council〔(【引用サイトリンク】title=Westsound Watersheds Council )〕 ==Needs== Pacific salmon rely on near-shore waters and estuaries for survival during a part of their life cycle. Salmon use estuaries and near-shore areas for migration, juvenile rearing, refuge, and feeding. Large trees in rivers are no longer common. The Nisqually River was in pristine condition when it was layered with log jams. It turns out, logjams actually help salmon, partly by slowing the speed of the river and by creating cool pools and channels that are good places for adult and juvenile fish to hide, feed and spawn.〔Kie Relya. ''The Bellingham Herald'', July 19, 2010.〕 When 90% of wetlands were lost, 90% of salmon was also lost.〔Montgomery, David. King of Fish The Thousand Year Run of Salmon. 2003〕 A Migratory Path Puget Sound’s near-shore region is composed of shallow saltwater, nearby wetlands, estuaries, beaches, and bluffs. These areas are critical zones for juvenile salmon as they make the transition from rivers to the ocean. Salmon are known to move through estuaries twice in their lifetimes. The first move is as juveniles when they move to the sea, and the second is as adults when they transition back to the rivers in order to spawn.〔Puget Sound Shorelines. 12 May 2005. Department of Ecology. 18 May 2011. A Place To Adjust Juvenile salmon spend a prolonged period of time (weeks to months) in estuaries in order to help ease their bodies adapt to the transition from fresh water to salt water. In a process called “Smoltification”, salmon are able to make the next step in preparing their bodies for the transition from freshwater to saltwater. Specifically, their bodies go through dramatic changes portrayed through their outward appearance, behavior, and even body chemistry. When these salmon return as adults they must go through the same process again in estuaries to help make the transition from saltwater to freshwater before heading back to their respective rivers to spawn.〔Puget Sound Shorelines. 12 May 2005. Department of Ecology. 18 May 2011. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Puget Sound salmon recovery」の詳細全文を読む スポンサード リンク
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