GENERAL INSPECTION:
We use a flashlight to inspect dark, recessed areas that rodents (mice and rats) frequent. When inspecting, we are looking for signs of activity: gnawing, droppings, and tracks. We are careful not to underestimate the size of the infestation resulting in under-baiting or under-trapping.

We begin the inspection from the exterior and work to the interior. We focus on areas that may provide water, food, or harborage: vegetation, refuse or wood piles, bird feeders, waterways, garages, carports, attics, crawl spaces, cupboards, closets, and food storage areas. Entry points are important to consider when inspecting: windows, door thresholds, utility lines, rooftops, and downspouts. Rodents have oily hair leaving smudge marks where they consistently travel. Droppings, urine trails, and gnawing marks all are signs of rodent activity. Feces are critical in determining the type of rodent and measure of activity. The feces of each type of rodent are listed further below and are discussed in detail.

SANITATION IS THE FIRST LINE OF DEFENSE!
You usually don't have an abundance of rodents without enough food and shelter provided. You can reduce the population considerably via sanitation just by the elimination of these sources. All rubbish piles and refuse need to be eliminated. Landscaped areas need to be properly maintained with woodpiles elevated off the ground. All garbage containers and dumpsters should have a tight-fitting cover. Rodents can live on the spilled and surplus food from bird feeders, along with dog and cat food. It is difficult to completely eliminate all food and shelter sources for mice, because of their small size and small food requirements.

For successful rodent exclusion, all openings greater than 1/4 inch should be sealed to exclude mice, but it may be impossible to seal all openings. All openings greater than 1/2 inch should be sealed for rats. Likely access points for rodents are where utility lines come into the walls, as well as openings around air conditioning, drain pipes, and vents. Hardware cloth can be used to seal these openings. Vents should be covered with a metal grillwork, and rust-resistant screening. Check to see that shingles are tight.

Rodents also cause damage to buildings by their burrowing and gnawing activity. The word rodent means "to gnaw". Rodents will gnaw through many types of materials in order to reach a location including lead sheathing, cinderblock, aluminum siding, and some concrete. They are able to squeeze through very small openings: 1/4 inch for mice and 1/2 inch for rats. We will be covering the three most common types of rodents.

HOUSE MOUSE

APPEARANCE:
The adult House Mouse is small and slender and measures about 1-2 inches long, excluding tail. It has large ears, pointed nose, and small eyes. The tail is as long as the head and body combined. The fur color varies, but it is usually a light gray or brown, but could be darker shades.

DIET:
Mice will eat almost anything, but prefer cereal grains, seeds, or sweet material. They require very little water, obtaining most of their water needs from their food.

HABITS AND BIOLOGY:
If there are good living conditions (food, water, and shelter), they can multiply rapidly. They sexually mature in two months, producing about 8 litters in a one-year life time. Each litter has 4-7 pups. A House Mouse in a city environment may spend its entire life in buildings. In rural and suburban settings, it may not only live inside, but be found outside near foundations, in the shrubbery, weeds, crawl spaces, basements, or in garages. They survive well on weeds, seeds, or insects, but when their food supply is shortened by the colder months, they move inside nesting closer to a food supply. They make their nest from soft material like paper, insulation, or furniture stuffing. These nests are found in many places including: walls, ceiling voids, storage boxes, drawers, under major appliances, or within the upholstery of furniture. Outside, the nests are found in debris or in ground burrows. Mice, while being "nibblers" eating many times at different places, do have two main meal times...just before dawn and at dusk...otherwise, they simply "snack" at other times at intervals of every 1-2 hours. They can eat about 10 to 15% of their body weight every day, the adults weighing about 5/8-1 oz. They get much of their water from food products.

INSPECTION:
Their droppings (feces) are about 1/8-1/4 inch long, and are rod-shaped. They gnaw small, clean holes about 1-1/2 inches in diameter. Many times in kitchens, you will find gnawing damage on the corner of boxes and paper, shredded for their nest. They will gnaw at bar soaps.

NORWAY RAT

The Norway Rat is larger and more aggressive than the Roof Rat.

APPEARANCE:
As an adult, the Norway Rat can weigh between 12-16 oz. with a body length of 6-8 inches long. Physical features include a blunt nose, small ears, and small eyes. The fur is shaggy and coarse with variation in colors. The tail is shorter than the head and body combined, and is scaly.

DIET:
They prefer foods with a high protein or carbohydrate content, but will eat almost any type of food. They need water to survive, unlike mice.

HABITS AND BIOLOGY:
The young rats reach sexual maturity in 2-3 months, females average 4-7 litters a year, with 8-12 pups per litter. Adults live about a year. They live in colonies. The Norway Rat generally prefers to live in underground tunnels. On farms, they will be near a food source: barns, granaries, livestock buildings, and silos. In the cities, they will be in the ground, if there is available space, but have been known to live entirely inside buildings. Rats will seek food outside, but many times will come inside at night to forage for food and return to their burrows. Needing a water source, they can obtain water from toilets, sinks, rain puddles, or condensation from utility pipes. Their nesting burrows on the outside are often along the foundation of walls. As the rat family grows, more burrows are built, resulting in a network of underground tunnels. Inside, the Norway Rat commonly nest on the lower levels, but if the population is too large, they may be found in the attic and ceiling areas. Their nests are built from soft material like paper or grass chewed into small pieces. Rats will climb if necessary to enter a building. The Norway Rat is an excellent swimmer. Rats are suspicious of changes in the environment or new foods. For this reason, it may take a couple of days for traps or poison baits to take. Rats are nocturnal, with their peak activity at dusk or before dawn. When the population is large, or they are disturbed or hungry, you can see activity during the day.

INSPECTION:
The droppings are 1/4 to 1/2 inch in length, capsule-shaped, with blunt ends. They are usually a shiny black, but may vary according to their diets. Norway Rats and Roof Rats will leave a hind foot track of about 3/4-1 inch, where a mouse's track measures 3/8 of an inch or less. Rats will also drag their tails, leaving a mark between their feet tracks. Unscented baby powder or flour, lightly sprinkled, can help you determine tracks and their runways as they cross suspected areas. Gnawing holes from rats are about 2 inches or more in diameter. They have rough edges. They prefer to gnaw on wood, but can damage electrical wiring. Rat burrows can be found along foundations, or beneath rubbish and shrubbery. If the burrow is active, it usually clears of vegetation. Rat runways are smooth and well packed. Indoors, these runways are free of dust and dirt.

ROOF RAT

APPEARANCE:
The Roof Rat is smaller and more slender than the bigger Norway Rat. The adults weigh about 5-9 ounces and measure 7-10 inches long. The tail is longer than the head and body combined. They have large ears and a pointed nose. The fur is smooth, as opposed to the Norway Rat with its shaggy fur

DIET:
They prefer seeds, nuts, fresh vegetables and fruits, but will eat meat and grain products.

HABITS AND BIOLOGY:
They become sexually mature in 2-3 months, with 4-6 liters per year, 4-8 pups per litter. The Roof Rat is a climber, commonly nesting in areas above the ground: trees, vines, attics, ceiling voids, or in voids along the roof line. These rats enter your home much like squirrels. As their population grows, they will nest in underground burrows.

INSPECTION:
Refer to the section on Norway Rat inspection. Much would be the same, except the droppings are spindle-shaped instead of capsule-shaped, and the droppings reach about 1/4 inch in size. The tail markings and hind feet markings are the same. Runways for Roof Rats are difficult to determine.

Rats and mice cause a huge loss of food world-wide. Besides eating our food, they spoil it by contamination with their feces, urine, or fur. They can be found not only in our homes, but supermarkets, restaurants, warehouses, food-processing facilities, livestock facilities, and farm fields. They reproduce rapidly and become active at night. Rats tend to be cautious, and mice are more curious. Rats tend to eat most of their food at one time, while mice will nibble a little at a time. It is important to remove their food sources, being careful not to disturb the rodent habitat. Food removal prior to control will cause the rodents to relocate to another area on the property.

A successful rodent control program includes a combination of trapping and baiting for the highest rate of success. If the population is large, you will want to begin with a high quality rodent bait to quickly reduce a population and prevent rapid growth. There are different types of baits to choose from: blocks, pellets, seeds....each rodent population are different in their preferences, so a little of each is a good choice in bait selections. When baiting initially, try not to disturb their original habitats, or they may move to another area close by. After baiting has begun, continue with sanitation procedures which include food source and harborage removal to ensure additional rodents from nearby areas are not attracted to your location.