Deer Mouse (Peromyscus maniculatus)

Identification • Behavior • Health Importance • CT Habitat

Deer Mouse – Connecticut Identification & Risk Guide

The deer mouse is commonly found in garages, attics, sheds, and rural homes throughout Connecticut. While they are not usually found in kitchens like house mice, they bring a greater medical relevance: deer mice are a known carrier of hantavirus in some parts of North America.

Identification:

• Color: Brown upper body with white feet and belly
• Tail: Two-toned (brown top, white underside)

• Eyes: Large, dark, and prominent
• Droppings: Similar size to house mice but more pointed

Behavior & Nesting:

Deer mice prefer:

• Storage bins
• Cardboard boxes
• Insulation
• Garages
• Attics
• Barns

They store food (seeds, nuts, crumbs) and create small nests of shredded material.

Why They Enter Connecticut Homes:

Most common in:

• Rural towns
• Homes near woods
• Cabins
• Unfinished basements

Temperature shifts in late fall drive them indoors seeking warm shelter.

Health Concerns:

Though hantavirus cases are rare in Connecticut, deer mice:

• Pose higher disease risk than house mice
• Spread urine and fecal contamination
• Carry parasites

Proper cleanup requires care: never sweep or vacuum droppings, as this aerosolizes particles.

When to Call a Professional:

Any sign of deer mice—especially in attics—requires proper exclusion and sanitation.

Rodent Control CT

• Moisture pests
• Attic pest identification