Many organisms migrate between distinct habitats, exploiting variable resources while profoundly affecting ecosystem services, disease spread, and human welfare. However, the very characteristics that make migration captivating and significant also make it difficult to study, and we lack a comprehensive understanding of which species migrate and why. Here we show that, among mammals, migration is concentrated within Cetacea and Artiodactyla but also diffusely spread throughout the class (found in 12 of 27 orders). We synthesize the many ecological drivers of round-trip migration into three types of movement—between breeding and foraging sites, between breeding and refuge sites, and continuous tracking of forage/prey—each associated with different traits (body mass, diet, locomotion, and conservation status). Our results provide only partial support for the hypothesis that migration occurs without phylogenetic constraint. Furthermore, our findings suggest that categorizing migration into these three types may aid predictions of migrants’ responses to environmental changes.
Bibliographical noteFunding Information:
We thank J Chapman, A Purvis, C Willis, B Zink, and two anonymous reviewers for comments. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-0646086 to AKS and funding for GEG through the Princeton Environmental Institute Grand Challenges Summer Internship Program.
© 2017 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
- IUCN Red List
- body mass
- movement ecology
- seasonal migration