For the more information about the geologic resources of the National Park Service, please visit http://www.nature.nps.gov/geology/.
- The seasonal movement of animals (whether individuals or populations) across different land or seascapes.
- The animals may differ by sex or age, yet the core pattern of mass directional movement returns them to the same seasonal ranges.
- The journey may be accomplished by individuals or span generations, such as is the case of the monarch butterfly.
Last Updated: December 21, 2010