Here's a breakdown:
* Salmon run: The annual migration of salmon from the ocean to their freshwater spawning grounds.
* Spawning grounds: The specific area in freshwater rivers or streams where salmon lay their eggs.
During their run, salmon face many challenges:
* Navigating to their specific spawning grounds: They use their sense of smell, sight, and possibly magnetic fields to find their way.
* Overcoming obstacles: They may encounter waterfalls, rapids, and other obstacles that they must jump over or swim through.
* Predators: They are vulnerable to predators like bears, eagles, and other fish.
* Stress: The journey is physically demanding and stressful for the salmon.
After successfully reaching their spawning grounds, the salmon will spawn, lay their eggs, and die. Their offspring will then hatch and make their own journey to the ocean, completing the life cycle.