Rats are present across Indiana, adapting to urban and rural environments where food, water, and shelter are available. Residents should understand their behavior and impacts.
Common Rat Species in Indiana
Indiana’s primary rat species are Norway and roof rats. Norway rats (brown or sewer rats) are robust, 10-15 inches long with a shorter tail (6-8 inches). They have brownish fur, blunt noses, small ears, and burrow, preferring ground or underground habitats.
Roof rats (black or ship rats) are more slender, 6-8 inches long, with a tail often longer than their body (7-10 inches). Their fur is sleek, black to dark brown. Unlike Norway rats, they are skilled climbers, preferring elevated nesting sites. Both are opportunistic omnivores.
Typical Rat Habitats
Rats seek environments with consistent food, water, and shelter. Indoors, they inhabit basements, attics, wall voids, and crawl spaces. Cluttered areas like homes, garages, and sheds provide hiding and nesting. Norway rats can squeeze through half-inch gaps; roof rats, quarter-sized holes.
Outdoors, Norway rats burrow under foundations, concrete slabs, and stream banks, also found in woodpiles, overgrown vegetation, and garbage areas. Roof rats prefer elevated outdoor habitats like tree canopies, dense shrubs, and climbing vines, using them to access homes via utility lines and fences. Sewers and dumpsters are common outdoor living spaces, offering consistent food and shelter.
Concerns Associated with Rats
Rats introduce property damage and health risks. They gnaw to prevent incisor overgrowth, damaging electrical wires, plumbing, structural wood, and insulation. Gnawing on electrical wiring can create fire hazards. Rats contaminate food and surfaces with droppings and urine, leading to spoilage and health issues.
Rats carry pathogens causing human diseases. These include leptospirosis (via contaminated water/soil) and salmonellosis (via contaminated food). Rat-bite fever results from bites or scratches. Hantavirus can transmit through airborne particles from droppings, urine, or saliva. Rats carry external parasites like fleas and ticks, which transmit other diseases.
Preventing and Deterring Rats
Minimizing rats involves preventative and deterrent measures. Sealing entry points is primary: inspect building exteriors for gaps, cracks, or holes, especially around utility lines and pipes. Use durable materials like metal mesh or steel wool, as rats chew through common building materials. Ensure doors and windows fit tightly and are properly sealed.
Maintaining a clean environment reduces rats’ access to food and nesting materials. Store all food, including pet food, in airtight containers. Regularly dispose of garbage in secure, lidded trash cans to eliminate food sources. Cleaning up food residues, crumbs, and spills on surfaces and floors makes an area less appealing.
Reducing clutter, indoors and outdoors, removes hiding and nesting spots. Regularly cleaning storage areas, garages, and basements deters them. Outdoors, trim overgrown vegetation and keep trees/shrubs cut back from the house to limit pathways and cover. Storing firewood 18 inches off the ground and securing compost bins helps prevent infestations.