Salmon

salmon fishingSalmon is the common name for several species of fish of the Salmonidae family. Several other fishes in the family are called trout. Salmon live in both the Atlantic and Pacific Oceans.

Salmon are anadromous: they are born in fresh water, migrate to the ocean, then return to fresh water to reproduce. Folklore has it that the fish return to the exact spot where they were born to spawn and modern research shows that usually at least 90% of the fish spawning in a stream were born there. In Alaska, the crossing over to other streams allows salmon to populate new streams, such as those that emerge as a glacier retreats. How they navigate is still a mystery, though their keen sense of smell may be involved. In all species of Pacific salmon, the mature individuals die within a few weeks of spawning.

Coastal dwellers have long respected the salmon. Most peoples of the Northern Pacific shores had a ceremony to honor the first return of the year. For many centuries, people caught the salmon as they swam upriver. A famous spearfishing site on the Columbia River at Celilo Falls was inundated after great dams were built on the river. Now, salmon are caught in bays and near shore. Long drift net fisheries have been banned on the high seas except off the coast of Ireland.

Table of contents
1 Food
2 Species
3 External Links
4 Further Reading

Food

Salmon is very popular as food. It is supposed to be very healthy because of the Omega-3_fatty_acids. Fish is more perishable than other meat, so some rules need to be followed. Ideally it should be cooked the same day it is bought. According to reports of the "Science" magazine farmed salmon contains a lot of dioxins. Also the PCB (Polychlorinated biphenyl) levels are almost 8 times higher in farmed salmon compared to wild salmon. However, according to the British FSA (Food Standards Agency) the benefits far outweigh the risks.

Species

The various species of salmon have many names.

Some young fish spend as long as four years in fresh water lakes before migrating to the sea. In rivers without lakes, many of the young move to the ocean quite soon after hatching. These salmon mature after one to four years in the ocean.

Some sockeye salmon live and reproduce in lakes and are called "kokanee". They are much smaller than the ones that go to the ocean (rarely over 14 inches long).

This species is netted for commercial canning, especially in Bristol Bay, Alaska, site of the largest harvest of sockeye salmon in the world, according to the Alaska Department of Fish and Game. The species has been preferred for canning due to the rich orange-red color of the flesh. More than half of the sockeye salmon catch nowadays is sold frozen.

  • Oncorhynchus tshawytscha is called chinook, king, tyee, spring salmon, quinnat, tule, or blackmouth. This species grows to a great size and may migrate for hundreds or thousands of miles up freshwater rivers to spawn. The young live in freshwater as fry for some time. Maturity occurs between the second and seventh year of life.

Chinook salmon are also called king salmon because many consider them to be the best tasting. Those from the Copper River in Alaska are particularly known for the color, flavor, firm texture, and high Omega-3 oil content.

  • Oncorhynchus gorbuscha is called pink or humpback. This species is found from northern California and Korea, throughout the northern Pacific, and from the Mackenzie River in Canada to the Lena River in Siberia.

The young hatch by mid-winter and migrate to the ocean by spring. They move into the deep ocean in the fall where they stay for two years. When mature, the pink salmons return to spawn close to the coast, some in intertidal areas.

Beginning in the late nineteenth century, fish traps were used to supply fish for commercial canning and salting. The industry expanded steadily until 1920. During the 1940s and 1950s, pink salmon populations declined drastically. Fish traps were prohibited in Alaska in 1959. Now most pink salmon are taken with purse seines and drift or set gillnets. Some increase in population is evident.

  • Oncorhynchus keta is called chum or dog or calico. This species has a wide geographic range: south to the Sacramento River in California in the eastern Pacific and the island of Kyushu in the Sea of Japan in the western Pacific; north to the Mackenzie River in Canada in the east and to the Lena River in Siberia in the west.

Most chum salmon spawn in small streams and intertidal zones, especially among stalks of eelgrass. The young feed on small insects in streams and estuaries, then move out to saltwater in the fall. They mature after three, four, five, or six years. Some chum travel more than 2,000 miles up the Yukon River.

  • Oncorhynchus kisutch (Walbaum) is called coho or silver. This species is found throughout the coastal waters of Alaska and up most clear-running streams and rivers. The eggs hatch in the spring. Young often spend the first winter in off-channel sloughs. Some fish leave fresh water in the spring, spend summer in brackish estuarine ponds and then migrate back into fresh water in the fall. Coho spend one to three winters in streams (or up to five winters in lakes) before migrating to the sea.

This species is a fighting fish and provides fine sport in fresh and salt water from July to September, especially with light tackle.

External Links

Further Reading

  • Trout and Salmon of North America, Robert J. Behnke, Illustrated by Joseph R. Tomelleri, The Free Press, 2002, hardcover, 359 pages, ISBN 0-7432-2220-2


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