According to the Pennsylvania Game Commission, mice in the wild sometimes eat spiders. They are omnivores, eating both plants and animals. However, mice prefer various types of vegetation.
Common plant-based foods consumed by mice include nuts, seeds, fruits, leaves and grasses. Occasionally they also feed on insects, larvae, snails and slugs; rarely, they eat birds’ eggs and other mammals. Most mice spend a significant amount of time searching for and storing food. Large portions of their stockpiles are saved for winter when food supplies are scarce, because most species of mice do not hibernate. The majority of mice are nocturnal, meaning they hunt for food and eat at night.