Natural History: This small rodent is active year round and is primarily nocturnal. In addition to houses, it may live in groceries, factories, or agricultural buildings where grain is stored. It also lives outdoors in old fields, pastures, or road sides. This species can be a pest by getting into food, and gnawing walls or clothing. It is omnivorous.

General Distribution: A native of Asia, the house mouse now occurs throughout the world in habitats associated with humans. In warmer climates, feral house mice may live in the wild, particularly in fields and other open environments. In the Presidio, the House Mouse is found in and around buildings.

Frequency: This is an abundant species within the Presidio.

Identifying Characteristics: This species is brownish with a long scaly tail and large, naked leaf-like ears.