Salmon lay between 3,000 to 15,000 eggs, but only 10% of eggs typically survive. They eat krill, herring, and other small fish and crustaceans. Salmon live for 2 to 8 years and are preyed on by various animals like snakes, birds, whales and bears. After mating, Pacific salmon die while Atlantic salmon can sometimes survive and spawn again. Salmon swim upstream to lay their eggs to protect them from being eaten by other fish.