Article

Mapping Migration Corridors for Conservation

Caribou in the Arctic
We're learning more about caribou from tracking their seasonal migration patterns. People in the Arctic depend on this resource. Tracking their movements and learning more about them help us conserve this resource for the future.

NPS/Kyle Joly

Migration, regular movements to and from different ranges, is important for a wide variety of wildlife. Some ungulates (hooved mammals) migrate seasonally to take advantage of new habitats, new food sources, water availability, protection for calving, and other reasons. Ecologically, these migrations are important because large numbers of hooved animals churn up the soil and add nutrients to keep plant communities healthy, offer prime hunting opportunities, and support populations of large carnivores and scavengers. In other words, these migrations benefit their entire ecosystem. Because animal migrations have been taking place for millennia, humans have depended on them for cultural, spiritual, and traditional food purposes. We’re finding migration is much more complex than we had previously understood. Migrating ungulates also face significant barriers and challenges. As our technology for tracking animal movements improves, we are learning more about the habitats they use, their life histories, and how and where they interact with people along their route. By mapping the migration routes and documenting what we learn, we can make better conservation decisions.

Wildlife movements are as diverse as the species themselves. Across the world, migrating ungulates include caribou in Alaska and Canada; Mongolian gazelles and saiga in Asia; wildebeest and zebra in the Serengeti; guanacos in South America; wild reindeer in Russia and Scandinavia; mule deer, pronghorn antelope, and elk in North America; red deer in Europe; and many others. They are a wonder to see and provide economic opportunities for wildlife watching tourism as well as hunting.

Because migratory species cover such large territories and move together, in large groups along a route, they face many challenges. Barriers to migration include habitat loss, physical barriers (fences, roads, etc.), and the impacts of climate change. Since migration is tied to seasonal ecological cues, such as green up and rainfall, changes in weather patterns causing large-scale drought or fire can shift migration timing or location or can be lost all together. If wildlife movements are restricted, the survival of entire populations can be at stake. We know from historical accounts that some migrations have already been lost—before we could even map them.

The Global Initiative on Ungulate Migration was launched with the publication of "Mapping out a future for ungulate migrations" in the May 7 issue of the journal Science. An international team of 92 scientists and conservationists, including members of the National Park Service, has joined forces to create the first-ever global atlas of ungulate migrations, working in partnership with the Conservation of Migratory Species (CMS). An environmental treaty of the United Nations, CMS provides a global platform for the conservation and sustainable use of migratory animals and their habitats. This unique treaty brings countries and wildlife experts together to address the conservation needs of terrestrial, aquatic, and avian migratory species and their habitats around the world.

Detailed maps of the seasonal movements of herds worldwide will help governments, indigenous people, and local communities to identify current and future threats to migrations and advance conservation measures to sustain them in the face of an expanding human footprint and climate change. Mapping will be based on animal tracking data, historical records, and local and indigenous knowledge.

Mapping out a future for ungulate migrations

Summary

Migration of ungulates (hooved mammals) is a fundamental ecological process that promotes abundant herds, whose effects cascade up and down terrestrial food webs. Migratory ungulates provide the prey base that maintains large carnivore and scavenger populations and underpins terrestrial biodiversity. When ungulates move in large aggregations, their hooves, feces, and urine create conditions that facilitate distinct biotic communities. The migrations of ungulates have sustained humans for thousands of years, forming tight cultural links among Indigenous people and local communities. Yet ungulate migrations are disappearing at an alarming rate. Efforts by wildlife managers and conservationists are thwarted by a singular challenge: Most ungulate migrations have never been mapped in sufficient detail to guide effective conservation. Without a strategic and collaborative effort, many of the world's great migrations will continue to be truncated, severed, or lost in the coming decades. Fortunately, a combination of animal tracking datasets, historical records, and local and Indigenous knowledge can form the basis for a global atlas of migrations, designed to support conservation action and policy at local, national, and international levels.

Kauffman, M. J., F. Cagnacci, S. Chamaillé-Jammes, M. Hebblewhite, J. G. C. Hopcraft, J. A. Merkle, T. Mueller, A. Mysterud, W. Peters, …, K. Joly, et al. 2021. Mapping out a future for ungulate migrations. Science 372 (6542): 566-569. doi: 10.1126/science.abf0998.

Last updated: May 6, 2021