Pacific Lamprey are native to the cold-water rivers of the Pacific Coast of North America and Asia. Pacific Lamprey are born in freshwater and then bury themselves in the river bottom where they filter feed for 3-7 years. After this larval period, juvenile Pacific Lamprey migrate to the ocean and become parasitic, using their suckerlike mouths to attach themselves to other fish or whales and live off the bodily fluids of these animals. Adult Pacific Lamprey live 1-2 years in the ocean and then return to freshwater to spawn. These fish utilize similar spawning habitat to salmon, laying their eggs in gravel. All Pacific Lamprey die after spawning.