Salmon

Adult Chinook Salmon

Photo by Roger Tabor - USFWS

 

Salmon may be a coveted sport fish in Alaska, but in fact each individual salmon's life is more fleeting and extraordinary than you might realize.

In the Seward Peninsula, a salmon's story begins in the freshwater streams and rivers that connect to the Bering Sea. At first camouflaged for the river, juveniles undergo extreme changes in both appearance and physiology as they begin their migration out to the ocean. Their gills and kidneys change to process saltwater, and their coloration transforms to match that of other marine species. In addition, their diet changes from plankton and insects, to small fishes.

By the age of 2 or 3 most salmon are full grown. Remarkably, at this age a salmon will return to spawn in the exact same river it was born in; it will only spawn this one time and die soon after. Before death however, a salmon will undergo more extreme changes in appearance, taking on a reddish color and developing a strongly hooked snout and large teeth. Females will prepare several nests and there the eggs will remain for about 6 weeks before the cycle begins all over again.

 

Chinook Salmon (Oncorhynchus tshawytscha)

The largest of all the salmon species, Chinook, or king salmon, can exceed 3 feet long and weigh 40-100lbs, and can be quite variable in size and appearance. A juvenile may spend anywhere from 3 months to 2 years in freshwater before venturing out to the open ocean, where it will remain for another 2-4 years before returning to its exact same river to spawn and die.

 

Coho Salmon (Oncorhynchus kisutch)

Following the same life history as other salmon, the Coho, or silver salmon can reach up to 2 feet long and weigh anywhere from 8 to 35 lbs. As the second largest salmon next to the Chinook, silvers spawn July-November and hatch from about May-June. Although silver populations have sharply declined in many parts of the west coast of the US, Alaskan populations remain healthy and abundant.

 

Sockeye Salmon (Oncorhynchus nerka)

Also known as the red salmon, sockeye are among the smaller of the salmon species, weighing 5-15lbs. Their meat is highly prized however, and gains its rich orangey-red color from the krill they eat while out at sea during their adult stage of life. After spending up to 3 years in the ocean, red salmon return to the freshwater streams of their birth, and develop red scales, a green head, and the distinctive humped back and hooked snout of other salmon species before spawning and dying.

 

Chum Salmon (Oncorhynchus keta)

The chum, or dog salmon, is widely distributed throughout the Pacific but occurs commonly around Alaska, some traveling nearly 2,000 miles upriver to spawn. Although their meat is not as highly prized as some other species, it is traditionally used as a source of dried food in the winter. Dog salmon migrate out to sea soon after hatching, and can grow up to 12lbs in their first 3-4 years in the ocean before returning back to spawn.

 

Pink Salmon (Oncorhynchus gorbuscha)

The other common name for pink salmon, the humpy, comes from a feature on spawning males. During the mating season, the male salmon develops a large hump on the back. The larger the hump, the greater the chance the male has of attracting a female. This mating strategy works surprisingly well and helps to make the pink salmon the most abundant Pacific salmon species. Every year, large amounts of pink salmon are caught and used as food by people living in western Alaska.