In general, steppe lemmings are friendly animals and prefer to live in colonies. Even small groups of males (preferably from the same litter) can live quite peacefully. However, males do tend to be territorial and a mature alpha male will nearly always attack a stranger and will often mistreat other members of his own litter, particularly if the nest is overcrowded. A large, well-filled terrarium (about 5–10 cm wood chips covered by about 10 cm of hay) can allow a group to live far more peacefully; altercations should be expected in smaller spaces with little bedding.