Rodents
Rodents’ instincts make them difficult to control, and they present a serious menace to your home. If you’re in need of rodent control services, here’s what you should know about these pests:
Rats
- Instincts: Rats are instinctively wary of rat control measures such as traps and bait, and colonize in attics, burrows, under concrete and porches, in wall voids, and other hard to reach places.
- Disease: Rats can harbor and transmit a number of serious diseases. They can also introduce disease-carrying parasites such as fleas, lice, and ticks into your home.
Mice
- Access: They invade your home seeking food, water, and warmth. Without mouse control intervention, one pair of mice may produce 200 offspring in four months.
- Contamination: Each mouse can contaminate much more food than it eats.
Rodents are warm-blooded mammals that, like humans, can be found throughout the world. They have oversized front teeth for gnawing and cheek teeth, which are adapted for chewing. Rodents chew on anything available to them and cause great damage in and around homes.
Rodents tend to be rapid breeders. Some species breed year-round. Although certain mice are known for short life spans due to predation, populations are maintained through constant reproduction. Because most rodents possess soft cartilage, they are capable of squeezing through spaces that appear to be much too small for them. All such holes should be stuffed with steel wool and sealed with spackle or cement to prevent entry and re-entry of rodents.
Rats and mice are both extremely destructive within agricultural communities. A number of species feed on seeds and grains. The feces and urine of some rodents may contaminate surfaces with which they come into contact.
Common Mice
Deer Mice
The Deer mouse is one of the most familiar rodents found in North America. Deer mice are named for their coats, which resemble the coat of the white-tailed deer. Deer mice have white bellies, with dark gray or brown backs and heads. These mice lighten in color at the underside and legs. They measure approximately six inches from nose to tail. The tail and body of the Deer mouse are approximately the same length. Their tails are brown at the tip and white near the base. The deer mouse's ears are large, round, and almost hairless. Their eyes are also comparatively large.
Deer mice are known to be the most significant reservoir of Hantavirus, which is transmitted through feces and urine. Hantavirus is extremely dangerous and is inhaled when it becomes airborne. Disturbance of droppings leads to release of Hantavirus particles. For this reason, vacuuming droppings is not recommended. Hantavirus Pulmonary Syndrome is transmitted when urine and feces are disturbed. Utmost care should be employed when disposing of deer mouse droppings. They should be sprayed with disinfectant before sweeping them up.
Deer mice are primarily herbivorous, but will also consume caterpillars, spiders and grasshoppers on occasion. They are particularly fond of grains, seeds, nuts and berries. As such, deer mice are formidable pests on farms and in the crop-yielding countryside.
In winter, deer mice enter domestic spaces in search of food and warmth. Their nests are constructed of fur, weeds, seeds, and paper. Although they become sluggish during cold months, deer mice do not hibernate. Deer mice hoard food supplies and actively forage for food near their nesting sites.
Although they also invade homes, deer mice are prominent in rural areas with weeds, tall grass, and plentiful vegetation. Deer mice create burrows and tunnel systems, which are much simpler than those created by other species. They use dry grass, weed stems, fur, and feathers to construct their nests.
House Mouse
Next to humans, the common house mouse is the most prevalent mammalian species in the world. Native to Asia, these rodents have spread throughout the world. They are most commonly seen living within or near human habitations. The house mouse is a small mammal named for its propensity to live within human habitats. They may also be used as laboratory subjects and contribute greatly to scientific studies.
The common house mouse weighs between 12 to 22 grams and may grow up 10 centimeters in length. They are black to light brown or gray in color, with short hair and lighter bellies. Gender may be difficult to determine in young mice, although age tends to accentuate sexual differences. Their ears and tail also bear hair, although much less than their bodies. Adult mice weigh approximately 40 grams and can grow up to eight inches from the nose to the tip of the tail.
House mice walk, run and stand on all fours. They can stand only on the hind legs, as well, and are supported by the tail, which also provides balance while in motion. The house mouse has a sharp sense of hearing and communicates with other house mice through squeaks. Some of these squeaks are audible to humans, while others extend into the ultrasonic range.
House mice are nocturnal and build nests in sheltered locations. They are extremely territorial. Males may be aggressive, while females tend to remain in the nest, protecting their young.
These rodents will feed on any available food source and may resort to consuming their own feces in the absence of other sustenance. Mice can chew through and cause considerable damage to plastic, paper, wood, and clothing. They are also potential carriers of disease.
Beyond their role as pests, house mice are helpful scientific subjects. Their physiology is similar enough to that of the human that they are used in important medical research.
Common Rats
Norway Rat
Norway rats are prevalent throughout North America. Arriving on ships from Great Britain circa 1775, these rodents quickly spread throughout the American Midwest. By the 1800s, they were present as far as Ontario, Canada.
Today, Norway rats thrive in a variety of human habitats. While it is believed that Norway rats originally lived only within temperate forest regions, they are extremely adaptive and now thrive comfortably in densely populated cities. Outside, they can be found burrowing in the soil beneath buildings, in embankments, and near tree roots. Inside, they live in basements, crawlspaces, attics and sewers. They can be carriers of various diseases.
The Norway rat is a large rodent that may weigh in excess of 500 grams. They can reach lengths of 400 millimeters and their tails alone may measure 187 millimeters in length. The body of the Norway rat is covered in fur that is brown or gray in color. Their ears and tail are covered in scales.
Norway rats are omnivorous and feed on a variety of food sources. If given the choice, they will consume meats, fruits, grain and nuts. Dead animals also serve as a food source for these rats, and they are capable of catching small fish and rodents. They require water to drink and they make their colony as close to a water source as possible. Norway rats live in communities with one dominant member.
Norway Wood Rat
There is a rat called the wood or pack rat. However, the rat that most people encounter is actually the Norway rat. The Norway rat was introduced to North America in the 17th century. Although of Asian origin, they spread to Europe before entering America via trade routes. Today, Norway rats inhabit human dwellings and thrive in urban areas, where an abundance of food is available.
Farmers also experience the ill effects of Norway rat infestations. Norway rats chew easily through wooden surfaces. They raid barns and warehouses, consuming feed, grain, and other packaged farm produce. Goods fed upon by Norway rats are usually contaminated by urine and droppings and are no longer of use to farmers.
Inside human structures, Norway rats breed prolifically throughout the year and as many as eight young may result from a single birth. Young rats are weaned within three to four weeks and become mature adults within six months. Norway rat infestations can become large and difficult to exterminate due to their prolific breeding habits.
Traditional traps may be ineffective if used alone in addressing Norway rat infestations. Rat-proofing methods may be undertaken to prevent infestations. However, in some situations, existing infestations can consist of hundreds of specimens and may require the services of a pest control professional.
Noregian Water Rat
Despite its name, the Norwegian water rat, also known as the brown rat or sewer rat, is more commonly called the Norway rat. This rat is not native to Norway. Rather, these rodents originated in Asia and were introduced via trade routes to Europe and finally to the Americas in the 1700s. Although initially native to forest and brushy habitats, Norway rats now live in close contact with humans.
Norway rats are sometimes mistaken for another species called the roof rat. The roof rat is smaller and lighter than the Norway rat. The tail of the roof rat is longer than its body. The tail of the Norway rat is shorter than its body.
Roof Rat
Black rats or Roof Rats have long been named as the cause of the Black Death of the Middle Ages. While this plague is no longer as serious a threat to humans, roof rats are still carriers of disease. They may transfer diseases to both human and domestic animals. They are highly adaptable, and prefer to live in high places, but may live in a variety of environments. They are nocturnal by nature and are accomplished climbers. As their name suggests, roof rats may be found in elevated areas such as trees, rafters, attics, and roofs. Roof rats can also nest on the ground if necessary.
The first step in controlling a roof rat infestation is to properly identify the rodents. Roof rats have hairless, scaly tails that are longer than their head and bodies. They leave oily marks on walls and dwell most commonly in attics or ceilings of buildings. Roof rats are prodigious breeders. Females are capable of producing up to eight pups per litter and can breed year-round. Within a year, one female may be responsible for up to 40 new rodents.
To prevent a colony from nesting in your home, make sure that all the windows and vents are screened. Roof rats can also enter openings in walls, eaves, and roof from the branches of trees. Trim all tree branches to further prevent entry. In dense populations, roof rats will establish a social hierarchy, wherein dominant males mate more than subordinate males. Lesser members of these communities may be expected to seek food during daylight hours.
The diet of the roof rat is similar that of the squirrel. They primarily consume fruits and nuts, although roof rats are omnivorous and will feed on almost anything available to them. These rodents have been known to consume tree bark, meat and grain. Roof rats are also food hoarders, hiding supplies of food too large to consume in one feeding.
Other Types of Rodents
Gophers
Moles
Voles
Cotton Rat
Chipmunks
Marmots
Woodchucks
Squirrels
Prairie dogs
Gerbils
Lemmings
Porcupine
Capybara
Agouti
For information on other pests, visit the "Pest Index" home page.
