Generally smolts tend to migrate northwards along the coast and will reach coastal Alaska by late summer. The southerly return migration occurs after about 12 months at sea. Many coho will swim a counter-clockwise circuit around the Gulf of Alaska. The route of migration is highly dependent on where the salmon find good feeding grounds. Coho can achieve speeds as fast as 50 kilometers per day on long voyages.
Coho are successful opportunistic feeders .
After a year in the ocean, the coho salmon returns to its home stream. Here it will swim to the area where it was born, and spawn. It will soon die. A series of imprints on the young salmon occur when they are initially migrating to the ocean. These imprints help guide them back to their native stream sections when they return to spawn.