Salmon spawn in fresh water rivers. The young migrate to sea after one to three years and return after up to three years at sea to spawn in their natal rivers. Pacific salmon occur from California north along the Pacific coast to the Bering Sea and Arctic Ocean waters adjacent to Alaska, and throughout the far eastern waters of Russia and Japan. There are five species of Pacific salmon:
Chinook or king salmon (Oncorhynchus tshawytscha): The largest Pacific species, these fish weigh an average of five-to-eight kg (11-18 pounds), live four to nine years, and are found from the Yukon River in Alaska to central California.
Chum, dog or keta salmon (Oncorhynchus keta): This species weighs an average of 3.5 kg (eight pounds), and is found in Japan, Russia and along the Pacific coast of North America from Washington state to Alaska. Large quantities of these fish are exported from Russia to China for processing.
Coho or silver salmon (Oncorhynchus kisutch): This species, which averages 5.5 kg (12 pounds), is caught from Oregon to Alaska and accounts for less than 10 percent of U.S. wild salmon catches in most years.
Sockeye or red salmon (Oncorhynchus nerka): These fish make up the second-largest, and most valuable, wild salmon fishery in North America, with 75 percent of the global catch originating in Alaskan waters. A major sockeye fishery in Russia supplies Japan and other Asian countries.
Pink salmon (Oncorhynchus gorbuscha): The most abundant species, pink salmon usually account for more than half of the U.S. commercial wild salmon catch. Large quantities are exported from Russia to China for processing.
The main commercial species of Atlantic salmon is Salmo salar, which occurs throughout European waters. There is a vast demand for salmon in Europe, North America and the Far East, with Japan the largest market. Commercial fishing of wild salmon takes place mainly at sea, although sport fishing for salmon in rivers is very popular.
About 60 percent of the global salmon market is farmed. Norway, Chile and the UK are the main producers, together accounting for 86 percent of all farmed salmon. About 89 percent of farmed salmon is Atlantic salmon. Pacific salmon is farmed in Canada, Norway, the UK, Chile, the U.S., and several Asian countries including Japan.
The dependence of salmon on specific freshwater areas makes them particularly vulnerable to habitat loss, which is currently the primary threat to their survival. The gear used at sea includes drift and set gillnets, purse seines, and trolling gear, which rarely touch the sea floor; these methods have low by-catch and cause little habitat damage.
Pacific salmon: Populations of Pacific salmon have declined dramatically due to overfishing and damage to their freshwater and spawning and rearing habitats caused by dam construction, deforestation and urban development. Chinook, coho, sockeye and pink salmon stocks in California, Oregon and Washington are significantly depleted, apart from a few viable large runs. Salmon from different areas are often caught at the same time, which complicates management. Thus, in California and the Pacific Northwest, there are some 30 locations called Evolutionarily Significant Units (ESUs), where salmon are listed as Threatened or Endangered under the U.S. Endangered Species Act and thus may not be fished; however they are regularly caught as they mix with or are found close to salmon from 'healthy' stocks. The northeast Pacific fisheries supply commercial markets in Asia, Europe and North America.
Atlantic salmon: Stocks of Atlantic salmon are threatened throughout much of their native range, due to habitat loss, overfishing, pollution, aquaculture and impediments to migration routes. Atlantic salmon is listed by the OSPAR Convention for the Protection of the Marine Environment of the North East Atlantic as a threatened and declining species.
Farmed salmon: Salmon hatcheries and farms have caused environmental problems in many areas. Hatcheries may be located in or near wild salmon runs, and escapes of hatchery-reared fish can threaten wild stocks by competing with them for food and spawning grounds. The impacts of salmon farming include:
Our website is not responsible for the information contained by this article. Articleinput.com is a free articles resource thus practically any visitor can submit an article. However if you notice any copyrighted material, please contact us and we will remove the article(s) in discussion right away.
Note: This article was sent to us by: Michael G. Crawford at 08252010
1. Hard Count Attendants also are responsible for emptying drop boxes
All articles are property of their respective authors. Please read our Privacy Policy!
© 2009 ArticleInput.com.
Partners: Damenmode