News Release

Confirmed! Caribou have the longest land migration in the world

Caribou have the longest terrestrial migration, but there is more to the migration story.

NPS/Kyle Joly

News Release Date: November 12, 2019

Contact: Kyle Joly

Caribou are often credited with the longest terrestrial migrations in the world, though without much scientific support. An international team of scientists, including Kyle Joly (National Park Service), Elie Gurarie (University of Maryland) and Mark Hebblewhite (University of Montana), gathered GPS collar data from around the world to address the question of which large terrestrial mammal migrates the farthest. Recognizing that not all mammals migrate, they also determined how far these mammals moved during the course of a year. The team’s findings have just been published in the journal Scientific Reports. Caribou, from numerous populations, were found to have the longest existing migrations in the world, with the round-trip distances exceeding 745 miles (1,200 km). Despite exhibiting the longest migrations in the world, a few species moved more than caribou in a year. Gray wolves and khulan (Mongolian wild ass) all moved more than caribou when considering their entire annual GPS track. A gray wolf from Mongolia captured the title of top terrestrial mover, having traveled 4,503 miles (7,247 km) in a year. To put this into perspective, it would be similar to you walking from Washington, DC to Los Angeles….and back…in a year.

The team discovered interesting patterns among these big movers. First, not only can predators keep up with their prey, they are often required to move much more in the course of their search for a meal. In Mongolia, gray wolves moved more than their prey, the khulan and wild camel. In Alaska, gray wolves moved more than caribou or moose. Second, small prey animals from the same region tended to move more than larger ones. For example, wildebeest moved more than zebras in the Serengeti, caribou more than moose in Alaska, and khulan more than wild camels in Mongolia. One possible explanation of this pattern is that large animals are capable of using lower quality food sources which are more abundant, and this allows them to move less overall. Lastly, higher movement rates by herbivores were associated with lower vegetative productivity. The less food that was available, the more they moved, likely to acquire sufficient resources. The greatest movements were found in areas of very low human disturbance, which highlights the effects of habitat fragmentation and human development.

For more information, see:

• web article
• Longest terrestrial migrations and movements around the world, Scientific Reports (2019)
• Climate change could be influencing the world's greatest terrestrial migrations, December 8, 2019, National Parks Traveler
• Longest Terrestrial Migrations, December 8, 2019, National Parks Traveler podcast, episode 43
• Caribou migrate a long way--but wolves travel even farther, November 22, 2019, The Wildlife Society
• Caribou migrate farther than any other known land animal, November 19, 2019, ScienceNews
• Still the undisputed champs of mammalian migrations, November 13, 2019, New York Times
• Longest terrestrial movements, November 8, 2019, Ecology and Evolution blog
• The animal that takes the crown for longest distance covered in one year, November 4, 2019, Nature online
• Who goes farthest? November 4, 2019, University of Maryland, Maryland Today