House Mouse (Mus musculus)

Identification

• Is the most commonly encountered of the commensal rodents in Canada
• Measures approximately 6.5 to 9.5 cm in length, from head to the end of the body (excluding tail)
• Tail is dark, scaly, and approximately 7 to 10.2 cm in length
• Can weigh anywhere between 12 and 30 g
• Fur colour will vary from region to region, but ranges from shades of grey to light brown, with the underside a cream or light grey
• Has pointed snout, small eyes, and large ears
• Droppings are approximately 3 to 6 mm in length, rod-shaped with pointed ends

Habitat and Behaviour

• Is inquisitive by nature, curious about new objects and situations
• Has poor sense of sight, but has excellent sense of hearing, smell, touch, and taste
• Is primarily nocturnal
• Prefers to nest in areas that are dark and hidden, with abundant nesting material
• Can penetrate through an opening as small as 6 mm to enter a structure
• Feeds opportunistically
• Seeks out warm areas once colder weather sets in and food availability is limited
• Can obtain daily water requirements from the food it consumes
• Typically travels between 1.2 to 1.5 m from their harbourage in search of food

Lifecycle

• Gestation lasts approximately 19 days
• Female averages 8 litters per year, with an average of 6 young per litter
• Sexual maturity is reached in approximately 35 days
• Lifespan is typically less than a year