When conditions are good, an individual may occupy a 10ha area. The maximum home range size is about 20ha. Home ranges of males are usually twice the size of female home ranges. These solitary mammals maintain exclusive boundaries that are patrolled and marked by scent. Adult males dominate females and young.
Females tend to remain in their birth place throughout their lives.
Males disperse and attain large territories that usually encompass or overlap females' territories. Habitat Ermine prefer riparian woodlands, marshes, shrubby fencerows, and open areas adjacent to forests or shrub borders. In the southern parts of their range, they live mainly in tundras, especially in vegetative areas next to rocky cover. Although ermine are primarily terrestrial, they climb trees and swim well. Tree roots, hollow logs, stone walls, and rodent burrows are used as dens.