1,200-Kilometer Caribou Migration: The World’s Longest Terrestrial Migration

Iconic cervids, caribou undertake each year a true migratory epic, traversing more than a thousand kilometers through the wild, icy landscapes of North America.

The Great Journey

As spring approaches, when the snowy mantle begins to melt, the tundra-caribou herds from Alaska and the Yukon head north toward the Arctic Circle. There, they enjoy environments rich in vegetation, with noticeably lower concentrations of predators and biting insects.

It is within this relatively tranquil setting that pregnant females give birth and raise their calves during the summer season. When temperatures start to dip toward late autumn, these cervids begin the long return journey to their more southern ranges, where food remains plentiful throughout the winter.

Although some terrestrial animals can perform longer migrations, a 2019 study published in Scientific Reports revealed that the round-trip distance for Rangifer tarandus averaged about 1,200 kilometers in a straight line.

This represents the largest distance ever documented for a species closely tracked throughout its migratory routine. In this case, the Bathurst and Porcupine herds. As the researchers note, boreal forest caribou groups, which offer more stable conditions year-round, lead a comparably more sedentary life.

Record Distances

When it comes to yearly distance traveled, the record is held by gray wolves. A few years ago, a male from southwestern Mongolia, driven by hunger and the search for mates, logged more than 7,247 kilometers in what amounted to an almost uninterrupted marathon. Driven by the pursuit of cervid herds, the packs in Alaska and the Yukon can cover about 5,630 kilometers within twelve months.

As impressive as these distances are, they pale in comparison with those covered by certain bird species.

In terms of nonstop migration, it is the red knot that takes the top spot, with a four-month-old individual covering 13,560 kilometers between Alaska and Tasmania in just 11 days. A remarkable feat involving a form of “self-cannibalism.”