Question

How do salmon travel to get back to where they were hatched?

Answer 1

Scientists believe that salmon navigate by using the earth's magnetic field like a compass. When they find the river they came from, they start using smell to find their way back to their home stream. They build their 'smell memory-bank' when they start migrating to the ocean as young fish.

Answer 2

When they find the river they came from, they start to use smell as a navigator to find their way back to their home stream. They develop this ability ("smell memory bank") when they start migrating to the ocena as young fish.