The Norway rat (Rattus norvegicus), also known as the brown rat, is the largest common pest rodent. It’s also the most frequently-encountered commensal (adapted to living near humans) rat species in temperate regions of the world. Norway rats damage materials by gnawing on, eating, and contaminating stored food. They also carry and transmit diseases and may also carry fleas.
Scientists believe Norway rats come from central Asian originally, but they’re now distributed worldwide. Norway rats live throughout the United States.
The adult Norway rat has a combined head and body length of 7 to 9½”. They typically weigh around 7 to 18 ounces. Their fur is coarse, shaggy, and brown with scattered black hairs; their undersides are gray or yellowish-white.
Norway rats have a blunt muzzle, small eyes, and small ears. Their tails are scaly and only slightly shorter than the rest of their body. Norway rat tails tend to be darker near the tip than they are near the base.
Norway rats are highly prolific breeders. Norway rat pregnancy only lasts around 21 to 25 days. A mother can produce litters containing between 2 to 14 offspring up to 6 times a year. Norway rats can and will breed all year, but they tend to reproduce less frequently in fall and winter.
Young Norway rats are blind and naked at birth. Hair appears in about seven days and the eyes open in 12 to 14 days. They are weaned at around 3 to 4 weeks. Norway rats reach sexual maturity within 2 to 5 months. Most Norway rats live between 2 and 3 years.
Norway rats are nocturnal and highly cautious. Although they constantly explore their surroundings, they tend to shy away from changes in their familiar environment. Outdoors, Norway rats prefer to nest in burrows in the soil near water and shelter like root systems or rocks.
Inside, Norway rats make small nests out of paper and garbage and prefer living in dark, secluded places. Like most rats, Norway rats are excellent runners, climbers, jumpers, and swimmers. They’re very good at following smells up to and through access points in the sides of buildings.
CONTROL AND PREVENTION
Norway rats enter homes for food, water, and shelter. To keep them out of your home, you have to deprive them of those three things. Rats have extremely keen senses of smell. They can smell food even through walls and packaging, and they’ll know if they can access it. Keep pantry food in airtight, hard plastic containers. Clean up meal prep and dining surfaces immediately after every meal. Vacuum up crumbs, wash dishes, and dispose of food remains as quickly as possible.
Controlling Norway rats’ access to water means controlling your home’s humidity. Look for and patch up any plumbing leaks, especially in your basement. Seal up drafts around windows and doors. Consider investing in a dehumidifier for your basement and/or attic. Finally, declutter as much as possible to deprive rats of shelter. Remove piles of firewood and other debris from around your home. Elevate and store boxes and bags instead of leaving them sitting out. Taking away food, water, and shelter will make your home far less hospitable to rats. When they can’t get what they want, they’ll go elsewhere.
A Plunkett’s technician will start by determining where norway rats may be entering the structure. From there, we can either seal off small access points or recommend repairs to close them off. We’ll also strategically place baiting traps indoors and occasionally outdoors, along foundation walls and under decks. Our tamper-resistant bait stations will contain rodenticide bait.
We may also apply rodenticide tracking powder (sparingly) into infested structural voids. If our baiting isn’t eliminating an infestation expediently, we may also place small snap traps in effective areas.
If you think you have a Norway rat infestation, don’t hesitate to call Plunkett’s Pest Control right away. We’ll take the necessary steps to wipe out your infestation and keep it from coming back.