Norway Rats

About Norway Rats

Norway rats are large, burrowing rodents commonly found in basements, crawl spaces, and lower levels of Orange County homes. Also known as brown rats or sewer rats, they are stocky with blunt noses and small ears relative to their body size. Norway rats are excellent swimmers and often enter structures through damaged drains and sewer lines. They are primarily nocturnal, feeding on a wide range of foods including garbage, pet food, and stored grains. Their burrowing habits can undermine foundations and damage landscaping, making prompt professional control critical.

How to Identify Norway Rats

• Brown or grayish-brown fur with a lighter underside, 7 to 9 inches long excluding tail
• Blunt nose, small ears, and a tail shorter than its body length
• Droppings are capsule-shaped, about 3/4 inch long
• Burrow entrances found along foundations, under debris, or in gardens

Lifecycle

Norway rats reach sexual maturity in about 3 months. Females produce 4 to 6 litters per year, each containing 8 to 12 pups. Gestation lasts approximately 21 to 23 days. In optimal conditions, a single pair can produce over 1,000 descendants annually, which is why early intervention is essential.

Health & Property Risks

• Transmit diseases including leptospirosis, salmonella, and rat-bite fever
• Cause structural damage by gnawing through wood, plastic, and even soft metals
• Contaminate food and surfaces with urine, droppings, and hair
• Create fire hazards by chewing through electrical wiring