Rodents

The Department of Health has a rodent control program that involves baiting for rats around residential properties and in alleyways upon request for free.  Education and code enforcement will also be conducted. To report a problem or schedule an inspection, please call (260) 449-7459 or click here.

Rodents and the fleas they carry are capable of transmitting a variety of diseases, Ratincluding plague, rat-bite fever, typhus and salmonellosis.

These diseases can be spread to humans directly, through handling of rodents, through contact with rodent feces, urine, or saliva, or through rodent bites. Diseases carried by rodents can also be spread to humans indirectly, through ticks, mites or fleas that have fed on an infected rodent.

The best protection from human exposure to rodent diseases is effective rodent control in and around the home. This is achieved by eliminating any food sources, sealing even the smallest entries into homes, and successfully trapping rodents.

Below you will find more information about identifying and controlling rodents, signs of infestation and other helpful resources.

Biology

The Norway rat (Rattus norvegicus) and the common house mouse (Mus musculus) are the prevailing rodent species found in Allen County.

Norway Rat

  • Adult rats are 12-18 inches long, and weigh up to 16 ounces.
  • Rat muzzles are blunt, and their bodies look thick and heavy.
  • Rats have small eyes, naked ears, and coarse fur; the ears are close to the body and do not cover the eyes when bent forward.
  • Rat tails are 6-9 inches long, scaly and nearly naked; the tails are shorter than the head and body
  • Rats have brown to dark gray fur, with scattered black hairs, and are gray, grayish brown or dirty white underneath.

House Mouse

  • The adult mouse has a small slender body weighing from ½-ounce to an ounce.
  • Mice have large, scantily haired ears; small black protruding eyes; a slightly pointed nose; and rows of scale ringing their long, tapered, sparsely furred tail which is usually equal to the length of the body, about 4 inches on average.
  • Mice usually have light brown to gray or black fur, with white or buff fur underneath.
  • A mouse’s life span is 9-18 months, although some have lived up to two years in captivity.

Rats usually live in underground burrows, but will inhabit wall voids.  They feed on garbage, meat scraps, cereal grains, vegetables, and cat and dog food, even the undigested food in dog and cat feces.

Rats are good swimmers, jumpers and climbers and they have keen senses of hearing, smell, taste and touch. They can enter any opening larger than ½-inch in diameter, which means they can squeeze into your home through the space around a pipe or conduit, under the door, through a hole in the screen or floor or though a gap between a window and its frame.

Outdoors, mice nest in weeds, rubbish, cracks in rocks or walls, or they will construct nests out of rags or paper lined with finely shredded material. In the wild, mice eat seeds, roots, leaves and stems, beetle larvae, caterpillars, cockroaches, and carrion, but they prefer seeds and grain.  When human food is available, those foods high in fat, protein, or sugar are often eaten in preference to seeds and grain. Some of their favorite human foods include bacon, chocolate, butter and nuts.

Like rats, mice are excellent swimmer, jumpers and climbers. They also have excellent senses of smell, taste and touch. While they have poor eyesight, mice have good peripheral vision that allows them to detect movement. Mice are curious, and will enter any hole or crack as small as ¼-inch in diameter.

Signs of Infestation

  • Droppings and urine trails left wherever they travel, especially in corners. Rat droppings look like little footballs; Mouse droppings look like pieces of rice
  • Dark smears and rub marks on baseboards as they move throughout their territories
  • Footprints and tail drags in dusty areas
  • Gnaw marks on wooden surfaces, especially door corners
  • A distinctive, musky odor
  • House pets may become agitated because they hear gnawing, digging, running and fighting

Rodent Control

Controlling rats and mice is more than just plugging entry holes, setting traps, and putting out poison bait.  The best control is to take away available food, water, and shelter.

Below you will find more information on these methods.

Sanitation
The first step is a cleanup program.  Rats and mice find shelter under old lumber piles and stacked firewood (should be stored 18 inches off the ground), piles of old papers, boxes, bags, broken-down sheds, trash dumps, high weeds and abandoned vehicles.  All such areas must be eliminated or corrected.  Any control program without environmental improvement will be ineffective.  These rodents can rapidly restore their original population levels due to their high birth rate.

Interior sanitation also needs to occur.  Once rats or mice are in your house, their population levels will increase if there is available food and water.  Remember rats will eat about anything.  If there is a cockroach problem, rats or mice can feed on the insects.  Clean up food crumbs and fix water leaks.

Rodentproofing
This means stopping the movement of rats and mice into buildings or other areas where they are not wanted.  Rats can squeeze through a hole the size of a quarter; mouse in housemice can move through a hole the size of a dime.  Favorite entranceways are poorly fitting doors and windows, holes around lead-in pipes and wires, dryer vents, joints between building foundations and walls, cracked siding, and unscreened doorways.  All such openings should be closed using sheet metal, hardware cloth or cement.  Doors and windows should be adjusted to close tightly.  It is also important to have tight-fitting covers on floor drains.

Population Reduction
There are five methods generally used for population reduction:  trapping, glue boards, burrow fumigation, tracking powders, and oral toxicants.

  • Trapping is a practical way of removing rats and mice, especially where poisons might be hazardous and where odors from dead animals would be objectionable.  The most effective and versatile trap is the wooden-based snap trap.
  • Glue boards involve the use of a non-toxic sticky substance on heavy squares of cardboard.  They are placed in active runways.  When the animals become trapped, they are killed and the board is thrown in the trash.  These are well-suited for restaurants and food-handling establishments.
  • There are several chemicals federally-registered for use as fumigants against commensal rodents.  They should never be used where there is danger of people or non-target animals coming in contact with the gas.  For that reason, most fumigants can only be used by professional pest control operators.
  • A tracking powder is effective when food is plentiful.  They work by having the rodent come into contact with it; then the rat or mouse cleans itself; and, the rodent ingests the poison.  Tracking powders should never be used in areas where there is any danger of the powder coming in contact with food or surfaces where food is prepared.
  • There are two general types of oral poisons:  single and multiple doses.  Killing success with single dose poisons depends on the animal consuming a lethal amount at one meal.  Multiple dose poisons have a lower concentration of toxicant.  They rely on several days of consecutive feeding.  No toxic bait is 100% effective.  Trapping is necessary for every last rodent to be removed.  Also, placement of bait inside a structure can cause several problems.  Children or pets may eat the bait and have adverse reactions.  Rats and mice that eat the bait may die in a wall void or other unreachable areas and produce a decomposing odor.  Reminder for citizens of the City of Fort Wayne – According to City Code, Chapter 91.025, Animal Care and Control, “No person shall set, use or employ any type of poisonous substance or bait within the city limits that the Department deems harmful to any domestic animal; provided, however, that controlled programs under the direction of the Fort Wayne-Allen County Department of Health or state licensed extermination service may be excluded in the discretion of the Department.”

Cleaning up Rodent Droppings and Urine
If there is a large amount of droppings and urine to clean up, it is important to take proper precautions to avoid rodent-borne disease that could be present.

  • Open windows for ventilation.
  • Wear gloves.
  • If a large amount of droppings and urine are present, wear a N-95 respirator mask.
  • Spray the droppings and urine with a disinfectant or bleach solution (1 part bleach per 10 parts water).
  • Wipe up with paper towels.  Throw the towels into the trash.
  • Spray the disinfectant or bleach solution on to the surface and wipe or mop.

For additional guidelines, see the CDC’s Cleaning Up After Rodents.

If you think you have a problem…

The Department of Health will provide a free inspection of your residential property.  When necessary, toxic baits will be placed outside the structure, at no charge. The bait is placed in secure bait stations and is not to be touched by the occupant/property owner as it is unsafe and may decrease the effectiveness of these control measures. Health department staff will recheck your property every 7-14 days until the infestation is eliminated.

Department of Health staff will not place bait inside the living areas of a structure, only outside the structure.  It is at the inspector’s discretion to bait in attics, utility basements, crawl spaces, and garages depending on the situation.  For safety reasons, employees will not climb into attics and/or crawl spaces to place bait. We cannot provide bait directly to the public due to federal law.  Here is our Rodent Bait Policy.

Poison Bait Labels & Safety Data Sheets

Please call us at (260) 449-7459 to schedule a free inspection.

 

Additional Resources