What Are Rats?

Rats are small, furry animals with prominent ears and long tails. Although rats often have a reputation for being dirty, vicious and harmful, the rodents are often the subjects of scientific research studies that result in important discoveries. However, because of their propensity for damaging food and crops and spreading diseases, rats pose a serious pest problem in much of the world.


What Do They Look Like?


Although the exact size depends largely on the species and the individual specimen, rats are typically between 13 and 19 inches long from snout to the end of the tail. Generally, the rodents weigh between 7 and 18 ounces.


Rats are usually either brown or black in the wild. Some species may appear gray, as well. Albino and spotted variations also exist. Technically, only the fur contains the color as rats have pinkish skin underneath.


An elongated tail is often the most recognizable characteristic of rats. The appendage drags behind the rodent and, in many cases, is equal to the length of the body. Other distinguishing features of rats include sleek fur, conspicuous ears and clawed feet.

More rat identification help.

Rats vs mice

Where Do Rats Live?

Outdoor Rat Habitats

In nature, rats nest in tree hollows, tall grasses, rock piles, and caves. All these hardy pests need is shelter and proximity to food and water. Because rats in Canada cannot live outdoors through the harsh winter months, they often look to homes as a place to stay.

Where Do Rats Live Indoors?

The ideal rat habitat is dark, moist, and concealed. This makes a variety of corners and crevices around the house the perfect place for rats to live. Homeowners usually find rodents living:

  • In the attic, where insulation provides a warm nesting space
  • Among clutter in basements, which provides plenty of cover
  • Inside wall voids, as these spaces allow them to travel throughout the house
  • Behind cupboards, which provide ready access to kitchen food scraps

What Do They Eat?

Rats maintain a largely omnivorous diet that varies depending on the species. Some common rat species prefer fruits, nuts and vegetation, while others favor grains and meat. When food sources become scarce, the small mammals may even resort to cannibalism and prey on younger and weaker rats. In general, the rodents are opportunistic and feed on whatever the pests discover while foraging.

Why Do Rats Bite?

People are rightfully concerned with whether rats can bite. Though common problems caused by rodents mostly involve property damage, the pests may also attack when they feel threatened. Norway rats and roof rats, two of the most common species, are also some of the most aggressive and have been known to strike even without being provoked. Therefore, it is likely that close encounters with rodents will lead to conflict.

Rat Bite Dangers

Rats bite hard, causing considerable pain with their strong teeth. In addition to discomfort, rat bites can also have more serious consequences. Rat saliva contains bacteria harmful to humans and pets such as the strain that causes rat-bite fever. Ignoring treatment can lead to severe brain, heart, or lung conditions and sometimes even death. When a person or animal has been bitten by a rat, it is crucial to seek medical attention right away.

Do Rats Hibernate?

Can Rats Survive Cold Weather?

While it would be helpful if rodents took a couple months off, rats do not hibernate. In fact, changing temperatures barely phase them if they have access to shelter and food. These pests are some of the most adaptable in the world, which is why they’re able to thrive in radically different climates.

Where Do Rats Go in Winter?

Even though rats do not hibernate, the pests do prefer warm shelter to harsh outdoor conditions. Unfortunately for homeowners, this means infestations become more severe during winter. Some rats choose to nest in warehouses or sheds, but the majority enjoy the comfort of living in people’s homes.

Do Rats Have Nests?

Norway and roof rats live in nests either below or above ground. The animals construct their homes out of fibrous materials like paper, grass, and cloth. These messy piles of debris are a breeding ground for disease-carrying ticks and fleas.

Where Do Rats Nest in Homes?

These pests build their nests in a variety of places in and around the house. While roof rats prefer to be high above the ground, Norway rats tend to live in burrows.

Common places for nests vary based on the type of infestation:

    • Roof rats – These pests are strong climbers, so they often make their nests in attics and rafters.
    • Norway rats – Because Norway rats prefer to be close to the ground, these rats’ nests may be in crawl spaces, basements, or around the perimeter of the house.

Both species can take up residence in a rotting tree trunk, woodpile, or other outdoor hiding place during warm weather.

Life Cycle

In the wild, rats live about six months on average due to hostile conditions and predation. In captivity or controlled lab environments, the rodents may live as long as three years. Common behaviors include climbing, swimming, gnawing and foraging. The rodents reach sexual maturity at around two to three months of age. Consistent with all other types of mammals, rats give birth to live young. Typically, 6 to 12 offspring result from a single pregnancy.


Problems Caused by Rats


Rats create potentially severe problems on many levels. One of the foremost problems is the spread of infections through rat bites and carried fleas. Historically, the pests inspired horror and were largely responsible for spreading the bubonic plague in the 1300s. Also called the Black Death, the plague wiped out vast numbers of the world population, with estimates reaching as high as 1/3 or more of all people on earth at the time. Though rats do not facilitate the same level of devastation today, the pests regularly carry pathogens for other harmful diseases.


By foraging persistently and gnawing on objects repeatedly, rats also cause damage to food, crops, and structures. Furthermore, the rodents engage in burrowing activities, which may lead to damage to gardens and landscaping. Some rats have even been observed stealing shiny objects.


Typical rat damage includes harm to structures and landscaping caused by their burrowing and chewing. Outdoors, Norway rats may leave unsightly holes in lawns or even undermine building foundations.


Indoors, both species are known for tearing up insulation, paper, and cloth to make their nests. They will also gnaw on wood and wiring between walls and in cars, creating the right conditions for electrical fires.

Rat damage may also result from the pests’ presence alone. Rats are strong swimmers, capable of entering homes through toilets. However, they can drown in the attempt, which clogs drainage pipes and septic tanks. Roof rat nests in gutters have a similar effect.

In addition, rodents contaminate stored goods and prep areas with their feces and urine. They have a preference for food in cardboard and paper packaging because it can be used as nest material in addition to a meal. Pantries, then, become common places to find the pests’ disease-ridden droppings.

In addition, many people find rats repulsive and even sickening. Merely catching sight of the pests may cause extreme discomfort and unease for homeowners. Though rats are not known to aggressively attack humans, the rodents may bite if cornered or threatened. Seek medical attention immediately if bitten by a rat.

Signs of Infestation

In addition to spotting rats in basement areas, gardens, or other sections of the home, several other signs serve as indicators of rodent infestations. Rats make noticeable burrows in garden areas. In addition, chew marks on crops, wires, some kinds of piping and wooden objects typically signify the presence of rats, as the mammals constantly gnaw on anything available to keep their teeth from growing too long.

Droppings are also a common sign of infestation and normally look similar in appearance to raisins. Smear marks and greasy prints may form on the paths that rats frequently tread as well.

Residents may also hear scratching, gnawing, and squeaking sounds if rats nest in the walls or ceiling. Since the pests are nocturnal, these noises often result in restless nights for homeowners.

Prevention Tips

Homeowners may take several preemptive steps to strongly reduce the possibility of a rat infestation.

To discourage these pests from living in close quarters with humans, food should be kept in airtight containers and any spills need to be cleaned up promptly.

Additionally, all garbage must be sealed in durable bins, as rats can gnaw through many materials to reach their food. Additionally, rinse items to be recycled and keep recycling in tight containers.

Install and maintain screens for all windows, especially those at the ground level, and check regularly for damage.

Properly insulating homes and ensuring all holes and crevices remain impenetrable also greatly helps to keep intrusive rodents at bay.

Staying proactive and preventing infestation in the first place often eliminates the need for further action.