Norway Rats in Louisiana: How to Identify and Remove Them in Lake Charles
Norway rats are the big, heavy rats that burrow along foundations, live under raised homes and come up through drains and garages. In Lake Charles, flooding and drainage ditches keep them close to houses. This guide covers how to recognize them, where they hide and how they are removed and kept out.
What Is a Norway Rat?
The Norway rat, Rattus norvegicus, is also called the brown rat, sewer rat or wharf rat. Despite the name, it did not come from Norway; it spread around the world on ships and now lives in nearly every city in the United States. It is the larger of the two rats found in Lake Charles homes.
Where the roof rat lives up high, the Norway rat lives low. It digs burrows in soil, lives under slabs and raised floors, and moves through drains, ditches and sewers. It is a strong swimmer and a determined digger, which makes it well suited to a wet, low-lying place like Southwest Louisiana.
How to Identify a Norway Rat
| Feature | Norway rat |
|---|---|
| Body | Heavy and thick, about 7 to 10 inches long without the tail |
| Tail | Shorter than the head and body, thick and scaly |
| Color | Brownish gray with a lighter gray belly |
| Head | Blunt nose, small ears, small eyes |
| Droppings | About 3/4 inch, capsule shaped with blunt ends |
| Where found | Burrows, crawl spaces, garages, basements of buildings, drains |
If you see a large rat moving along the ground with a stocky body and a short tail, it is almost certainly a Norway rat. Smaller rice-sized droppings in a pantry point instead to a house mouse.
Norway Rat Habits and Behavior
They burrow
Norway rats dig networks of tunnels about the width of a fist at the entrance, usually along foundations, under concrete slabs and sidewalks, beneath woodpiles, and along the banks of ditches. A burrow often has more than one opening so the rats can escape.
They stay low
They can climb, but they prefer to stay on the ground. Inside a home, they show up in crawl spaces, garages, lower walls and under kitchen floors rather than in the attic.
They swim
Norway rats are strong swimmers. They travel through storm drains and sewer lines, and they can enter buildings through floor drains and broken pipes.
They eat almost anything
They will eat garbage, pet food, birdseed, meat scraps and grain. Trash cans, compost piles and dumpsters near a home are a steady food source.
They live in family groups
A burrow system usually holds a group of related rats, not a single animal. Females breed several times a year, so one active burrow by the slab often means more rats nearby. When you see one Norway rat in daylight, it can be a sign the group has grown large or its food supply is under pressure.
8 Signs of Norway Rats Around Your Home
- Burrow holesFist-sized holes along the foundation, slab edges, steps or fences.
- Packed dirt trailsWorn paths in grass leading from burrows to the house or trash area.
- Large blunt droppingsCapsule-shaped droppings in the garage, crawl space or along walls.
- Noises under the floorHeavier thumps and scratching below the floor rather than overhead.
- Gnawed doors and pipesChewed bottoms of garage doors, wood trim or plastic pipes.
- Rub marks at ground levelGreasy smudges along the base of walls and around openings.
- Trash torn openBags ripped and food dragged away overnight.
- Rats near drainsRats seen near storm drains, ditches or floor drains.
Why Norway Rats Thrive in Lake Charles
Lake Charles sits low, with bayous, drainage canals and ditches running through neighborhoods. Those waterways give Norway rats travel routes and burrowing banks close to homes. Contraband Bayou and the many drainage ditches across the city are good examples of the kind of habitat they use.
Flooding pushes them toward houses. When heavy rain fills their burrows, Norway rats move to higher, drier ground, which often means the space under a raised home, a garage, or the gap under a slab. Calcasieu Parish has had several serious floods since 2020, and each one sends rats looking for new shelter.
Many Lake Charles homes are raised or pier and beam, with skirting and vents that can be damaged by storms or age. That gives Norway rats a dry, protected space right beneath the floor. Crawl space rodent control is built for that problem.
Loosely plug a burrow hole with crumpled newspaper or soil and check it the next day. If it's been pushed open, the burrow is active.
Damage and Health Risks From Norway Rats
Norway rats gnaw through wood, plastic pipes and even soft concrete and mortar. Burrows can undermine sidewalks, slabs and steps over time. Under raised homes, they tear ductwork and insulation and chew wiring.
Because they live in drains and water, Norway rats are closely linked to leptospirosis, which spreads through urine in water and soil and becomes a bigger concern after floods. The rodent diseases guide explains the risk in plain terms.
After flooding, avoid wading in water near ditches and burrows, and wear gloves and boots when cleaning up. Rat urine in water and mud can spread leptospirosis.
How Norway Rats Are Removed
Norway rat removal focuses on the ground level, the crawl space and the burrows themselves.
Ground-level inspection
The technician maps burrows, trails, crawl space openings, garage gaps, drains and pipe penetrations, and checks for damage.
Trapping on the runways
Traps go along walls and trails in the crawl space and garage. Outside, any bait stays in locked stations. This is part of standard rat removal.
Seal low entry points
Skirting, vents, door bottoms and foundation gaps are closed with metal and mesh. Exclusion sealing carries a 90-day guarantee.
Close the burrows
Once activity stops, burrows are collapsed and filled so new rats can't reuse them.
Follow up
The technician returns to check for new burrows and confirm the rats are gone.
How to Keep Norway Rats Away
Norway rats need food and cover near the ground. Remove both and they move on. These habits matter most for homes near ditches, bayous or open lots, where new rats arrive every rainy season.
- Use trash cans with tight lids and keep them off bare dirt if you can.
- Store firewood and lumber off the ground and away from the house.
- Keep grass and shrubs trimmed along the foundation.
- Pick up pet food at night and store it in metal bins.
- Fix broken skirting and vent screens right away.
- Make sure floor drains have covers and outdoor pipes are not cracked.
Norway Rat FAQs
What is the difference between a Norway rat and a roof rat?
Norway rats are bigger and heavier, with small ears and a short tail, and they live and burrow at ground level. Roof rats are slimmer, with large ears and a long tail, and they live high in attics and trees.
Can Norway rats come up through toilets or drains?
They are strong swimmers and do travel through sewer lines, so it can happen, though it is uncommon. Broken pipes and uncovered floor drains are the more common way in.
How big do Norway rats get?
The body is usually about 7 to 10 inches long, plus a tail that is a bit shorter than the body. They are noticeably heavier than roof rats.
Do Norway rats live in attics?
Rarely. They prefer the ground level. If you hear rats in the attic, it is much more likely to be roof rats.
Why did Norway rats show up after a flood?
Floodwater fills their burrows and drains, so they move to the nearest dry, sheltered space. Under a raised home or inside a garage is a common choice.
How much does Norway rat removal cost in Lake Charles?
It starts with a $350 inspection and a $500 trapping program. Sealing usually runs $200 to $4,000 or more, and crawl space cleanup runs $700 to $5,000 or more when needed.
Related Guides and Areas
Norway rats are common near water and drainage in areas like Westlake and South Lake Charles. For all services in one place, see rodent control in Lake Charles, LA.
Get Norway Rats Out From Under Your Home
Ground-level trapping, sealed skirting and vents, and burrows closed for good.
(337) 651-2150