10. Salmon, 3800 Kilometers
Salmon fishes have one of most impressive migratory power in animal kingdom, they traverse between freshwater and saltwater. After hatching of eggs salmons remain in river waters for 2-3 years. During that time salmons undergo many physiological changes. These changes help them to migrate to seas waters without facing much obstacles. For next 3-4 years they prefered to live within salt water. Reproductive capacity within this species of fish will develop during that time.
Then they migrate back to fresh water, the exact river where they born, return to home for spawning. The exceptional navigation power itself help salmons to make their return journey from saltwater to freshwater, their brain can detect exact magnetic field of their birth place. Their ability in jumping and sense of smell also help them during their extreme migration, will cover up to 3800 kilometers in a complete migration. Salmon is the common name for several species of ray-finned fish in the family Salmonidae.
Other fish in the same family include trout, char, grayling and whitefish. Salmon are native to tributaries of the North Atlantic and Pacific Ocean. Many species of salmon have been introduced into non-native environments such as the Great Lakes of North America and Patagonia in South America. Salmon are intensively farmed in many parts of the world.
Typically, salmon are anadromous: they are born in fresh water, migrate to the ocean, then return to fresh water to reproduce. However, populations of several species are restricted to fresh water through their lives. Various species of salmon display anadromous life strategies while others display freshwater resident life strategies. Folklore has it that the fish return to the exact spot where they were born to spawn; tracking studies have shown this to be mostly true.
A portion of a returning salmon run may stray and spawn in different freshwater systems. The percent of straying depends on the species of salmon. Homing behavior has been shown to depend on olfactory memory.