Coho Salmon Habitat
Wood debris in the river and from undercut riverbanks effects Juvenile Coho Salmon fishing, movement and position in the stream.
Effects of Wood debris on Juveniles Coho Salmon
Juvenile Coho Salmon respond very well to food abundance in rivers and streams, which I am sure is not surprise to you.
However, the point you may not be aware of is that the abundance of wood debris in the river and over hanging river banks increases their movement from pools of water and has them feeding more aggressively.
Pools with either high densities or total lack of woody debris attracted proportionately less fish. Moreover, decreases in water temperature and increases in water flow rates increased the number of Coho Salmon that head downstream.
Coho Salmon Annual Migration
Most Coho Salmon migrate only a short distance in the fall to spawn. Coho Salmon from California to British Columbia tend to travel north and spend the summer along the central Alaskan coast.
Most Alaskan fish travel a counter clockwise path following the currents in the north Pacific ocean. Coho Salmon smolts tend to stay close to shore at first, feeding on plankton. As they grow larger, they move farther out into the ocean and switch to a diet of small fish.
Freshwater and Saltwater Habitat
Coho salmon can live in freshwater alone without need to migrate to the ocean. However, those Coho Salmon living in their native distribution migrate to the ocean shortly after birth, stay in the ocean for a few hours before returning to their birth river to spawn where they die shortly after spawning.
Coho salmon prefer lower stream water currents, shallower water and small gravel. Most Coho Salmon fry stay in their birth stream for anywhere from 12 months to 18 months before heading to the sea. However, much of this time is spent in the river estuary.
Adequate stream cover is important to fry survival. As indicated above, they prefer gravel river beds that have adequate wood debris offering protection. They also prefer a habitat with plenty of food.