For countless generations, they have sustained the livelihoods of Indigenous nations across the Arctic. The longest known shark migration was recorded in 2003, by scientists tracking a great white between the coasts of South Africa and Australia. Every year, the Porcupine caribou herd embarks on the longest land mammal migration in the world, covering over four thousand kilometres of the Northwest Territories, Yukon and Alaska. When this happens, the calves are born along the migration routes and on calving habitats in Canada. The farthest distance travelled by a migrating land animal belongs to Grant's caribou (Rangifer tarandus granti) of Alaska and the Yukon Territory of North America, which travel … When caribou populations decline, they tend to migrate shorter distances and, sometimes, not at all. Large regional herds of between 50,000 and 500,000 animals travel seasonally, taking advantage of food resources while avoiding predators and coastal insects. Once migratory patterns are lost, they aren’t often regained or relearned again. It is the most common form of migration in ecology. The journey, some 6,900 miles, took the shark a … Conversely, when caribou herds swell in size, they tend to move the longest distances, the researchers found. Caribou travel up to 3,000 miles a year, and their migrations are the longest documented movements of any land animal.

In years when there's deep snow on the winter range and along the migration routes, and when the spring snow melt is delayed by cold temperatures, caribou cows are delayed in reaching these preferred calving grounds.

It is found in all major animal groups, including birds, mammals, fish, reptiles, amphibians, insects, and crustaceans. Caribous will covers up to 70 kilometers in a single day during migration, have power to run up to speed of 80 km/hr and can swim at 10km/hr.

During summer season they start migration in searching for food. Caribou are the lifeblood of northern ecosystems. They form large herd that have members up to 50000 reindeers before starting migration. Animal migration is the relatively long-distance movement of individual animals, usually on a seasonal basis. This happened in 1987, 2000 and 2001.