How do salmon find their way back to their spawning grounds?

Salmon use a combination of environmental cues, including Earth’s magnetic field, water chemistry, and their sense of smell, to navigate back to their spawning grounds. They imprint on the unique chemical composition of their natal river as juveniles. When it’s time to spawn, they follow these chemical cues upstream, sometimes travelling hundreds or thousands of kilometres. This extraordinary homing ability ensures that salmon reproduce in a familiar and suitable environment, completing their life cycle.