Deer mice are very active in the Okanagan. They live in several different habitats such as alpine habitats, northern boreal forests, desert, grassland, bushy areas, orchards and vineyards.

Deer mice have many litters per year in the wild. Reproduction may not occur during the winter months. Females can become pregnant shortly after giving birth. The gestation period is 22 to 25 days as long as they are not nursing the young and the gestation period of a female nursing is 24 to 30 days. Each litter can contain from 1 to 11 deer mice but most commonly four to six. The litter size increases after each birth until the fifth or six litter then it starts to decreases. The juvenile deer mice at birth are helpless but develop quickly and after 35 days they can reproduce; however, they usually breed for the first time at 49 days. In captivity deer mice can live up to eight years. The life expectancy in the wild is about one year.

Deer mice are most active at night. They spend most of their time on the ground but they are amazing climbers and can jump about 3 feet straight off the ground from a standing still position. In the wild, during winter, deer mice will huddle together with different sexes and ages. During the winters deer mice will move into structures especially occupied buildings with food and heat. Once inside they will destroy boxes that contain food and gather the food and nesting materials.

Each mouse makes about 50 droppings per day. Deer mice can fit through a quarter inch opening. Some deer mice are carriers of the Hantavirus pulmonary syndrome (HPS). HPS is an illness that is caused by a virus called Hantavirus, which is in the droppings, nesting materials and urine. It is mainly spread when these items are disturbed sending virus particles into the air where they can be breathed in. Early signs of HPS are flu-like symptoms such as fever, sore muscles, headaches, nausea, vomiting and shortness of breath. If the symptoms are untreated, fluid can build up in the lungs making it hard to breath. In North America roughly 1 out of every 3 people that contract the virus will die. Rodent droppings should always be cleaned up by a pest control professional with all the right safety gear and knowledge to protect the home and owners.