How old are salmon when they migrate from fresh water to the ocean?

That depends on species:

• Chinook
  • Fall Chinook, 3-4 months after hatch;
  • S pring Chinook, 12-16 months;
• Coho--12-24 months;
• Chum--a week to a month;
• Sockeye--12 months to 36 months;
• Pink--a week to a month.