• Colour Brown, black, grey, or white
  • Size From 30 cm to 50 cm long
  • Description Have coarse fur, protruding ears, and tails.

General Facts

Rats are mammals of the genus Rattus. The most commonly encountered commensal rat species in Canada are the Norway rat (Rattus norvegicus), also known as brown rats, and the roof rat (Rattus rattus), or black rats. Distinctive characteristics primarily include coarse fur, protruding ears, and long tails. Rats are of significance because they not only transmit and spread disease-causing germs but also can cause structural and aesthetic damage to property and food losses. In addition, people generally react with negativity and revulsion upon encountering the small mammals. The rodents pose a severe pest problem throughout virtually all populated areas of the world, including Canada.


The two rat species have different and distinct features. The roof rat is most recognizable because of its long tail which drags behind it as it moves. The tail is often longer than the rest of the body. The body measures about 41 cm in length, is slick and lean with brown to black fur, and weighs between 150 and 250 g. The ears and eyes are large with pointed snout. The Norway rat on the other hand is stocky, heavy body, short tail with the body measuring about 30 to 50 cm. Its eyes and ears are small with blunt snout. The body has brown or black colouring, though some species may appear gray or white, as well.


Rats are present in Europe, Asia, Africa, Australia, and the Americas. The widespread population shows no signs of decreasing. In fact, brown and black rats are both considered abundant and of least concern of endangerment or extinction. The highly adaptable animals thrive in areas where humans live and feed on any obtainable food sources, which greatly diversifies the available habitats for rats.


While specific eating habits may differ slightly between particular rat species, the rodents generally eat anything. As omnivores, rats adhere to a mixed diet consisting of grains, fruits, nuts, vegetables, and meat. However, the Norway rat has been shown to prefer foods high in fat content such as grease and meat. Meanwhile, roof rats prefer grains, nuts, seeds, and plant-based foods.

Life Cycle/Reproduction

Rats usually only live to about six months of age in the wild. They reach sexual maturity at around two to three months old. Pregnancies last between 20 and 30 days and typically result in 6 to 12 offspring. Though the rodents possess short lifespans, the rapid rate at which they reproduce, coupled with short gestation periods and large litter sizes, allows rats to continue as formidable pests.

Problems Caused by Rats

The gnawing and foraging behaviours of rats often lead to food and structural damages in homes. During the pursuit of nourishment and nesting areas, the rodents may leave smudge marks and droppings behind, as well. Many people find rats disgusting and/or frightening and react with horror upon seeing the pests. Rats very rarely bite but will do so if provoked or trapped. In addition, rats can transmit pathogens directly on their bodies, saliva, urine, droppings, or thorough vectors such as fleas and mites. The rodents infamously proliferated the Black Death, which led to the deaths of millions of people in the 14th century. Though the pests do not carry the plague today, the spread of disease by rats is still a serious cause for concern.

Rat Diseases

The two types of commensal rats most likely to be found in Canadian homes are the Norway rat and roof rat. Because of their biology and behaviour, they act as disease reservoirs and have the potential to carry dozens of diseases that can be spread to both humans and pets. Rat diseases may be transmitted directly through bites, body fluids and droppings or indirectly by the parasitic insects, ticks and mites that feed on them or nest in their fur. I tis important to be vigilant, since rodents prefer to live in close proximity to humans, the potential risk of transmission of rat-borne disease to humans can exist.

Rat diseases that can be spread directly include rat-bite fever, salmonellosis, leptospirosis, and E. coli infection. Rats are also infested with ectoparasites such as fleas, ticks, and mites that are vectors of various pathogens. When infected fleas, mites, and ticks bite people, they can transmit the pathogens to humans. For example, the infamous plague, although it’s a rare disease in North America today, it is transmitted from rats to humans via plague infected fleas that feed on infected rats and then on humans. Rocky Mountain spotted fever, tularemia, or Lyme disease can be transmitted via ticks.

Protection from Rat Diseases

The best protection against rat diseases is to make sure that as homeowner you control and prevent rat infestations promptly. Be well informed, know what signs of rats look like, and practice preventive measures to keep rats off your property and from getting indoors. Practice good sanitation, habitat reduction-to help eliminate potential harbouring sites on your property. Seal and close holes that might allow them in. Sanitize rodent contaminated surfaces with regular household sanitizers, dispose of rodent contaminated edible products; always wear a face mask and protective gloves when cleaning any build-up of rat droppings. In case of an infestation, contact Orkin Canada. Our trained professionals will safely and effectively eliminate your rat problem.

Detection/Signs of Infestation

Rats are often heard rustling, squeaking, or gnawing while in hiding. The constant gnawing of rats also leaves telltale damage, like teeth marks, on hard surfaces. Other signs of a rat infestation include droppings, footprints, nests, and the visible trails formed when the rodents travel the same path repeatedly while foraging for food.

Identifying Rat Damage

The most common commensal rat species in Canada are Norway and roof rats. Norway rats are larger than roof rats; stay near ground level and in burrows. Roof rats prefer to nest in trees, attics, and rafters. Typical rat damage to structures and landscaping is 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.

Rats are strong swimmers, capable of entering homes through toilets and drain pipes. However, they can drown in the attempt, which can clog drainage pipes and septic tanks. Roof rat nests in gutters can have a similar effect. In addition, rodents can contaminate stored goods and prep areas with their feces and urine. Roof rats in particular have a preference for food in cardboard and paper packaging because it can be used as either nesting material or a meal. Pantries, then, become common places to find the pests’ disease-ridden droppings.

Prevention and Removal

Cleanliness, habitat modification, and exclusion is the key to rat prevention. Kitchens that are swept regularly and kept neat are less likely to invite infestations. Trashcans with lids should be shut tightly and all food products should be sealed in rat-proof containers. A well-groomed landscape and yard helps eliminate harbourage sites for rats. Since rats can enter through small openings, it is important to seal and close openings that are greater than ½” to help prevent entry points. There are various types of mechanical traps available to catch rodents indoors, but they can be a safety hazard to pets and children when not set and monitored correctly. Therefore, if you see signs of rat damage, or suspect you have rat problem, it is best to contact the trained professionals at Orkin Canada to manage them safely and effectively.

Rat Droppings

Homeowners who find small animal droppings in attics, basements, or around baseboards often have a rodent infestation. It’s important to identify the droppings in order to employ the correct removal tactics. Rats defecate frequently while moving, so droppings are usually dispersed at random rather than in clusters.

Additionally, rat poop is dark brown or black, long, and spindle-shaped. In general, rat droppings look like raisins, whereas mouse droppings are much smaller and resemble dark grains of rice.

The Dangers of Rat Poop

The most common species of structure infesting rats in Canada are the Norway rat and the roof rat. Some disease-causing pathogens found in these pests’ waste include Leptospira and Salmonella.

The most frequent method of transmission of these pathogens is through inhalation, which occurs when dried rat droppings are disturbed and the viruses or bacteria inside become airborne. Disease is also spread through contaminated food and liquids when rats feed on stored pantry items.


Rats can enter homes through crevices as small as 12 mm. Therefore, prevention begins with properly screening doors and vents, as well as sealing any cracks in walls. Perhaps the most effective measure is cleanliness. A tidy house without easily accessible food is less likely to attract rodents in the first place.

If a rat infestation is already suspected, homeowners should be cautious when cleaning in dusty and confined areas without proper ventilation. Since disturbing rat droppings can spread disease, it is safest to contact the professionals at Orkin Canada for prevention and removal services.

Rats in Attic

Once indoors, roof rats cause multiple problems for homeowners. The agile, climbing pests get their name from their tendency to move into the attics or rafters of homes and buildings.

The most common indicator of rats in the attic can include scratching sounds in the walls and ceilings, often heard at night. Additionally, homeowners may find signs of chewing, droppings, nests and damaged pantry goods.

Removing Rats in the Attic

Rats are pests due to their need to gnaw on everything in sight. This is an especially serious problem in the attic, where easy access to wiring and insulation can lead to electrical fires, power outages, and expensive repair work.

Additionally, rats carry a plethora of diseases and may contaminate stored food and kitchen appliances with their filth. Though residents can try removing rats in the attic with store-bought traps, those unfamiliar with them typically find them time-consuming and inefficient. Instead, rely on the pest professionals at Orkin Canada to control rat infestations.

Rats in House

Though every province makes an effort to eradicate rats, these filthy pests still persist in many provinces. The Norway rat and roof rat are the two most common species of rats in the country.

Norway rats are stocky and larger (18-25cm and 200-500g) then the more slender roof rat (16-20cm and 150-250g). The fur of a Norway rat is coarse and shaggy while the roof rat is soft and smooth.

Although they may initially look similar in size and colour, they are also differentiated by their behaviour. For example, Norway rats are known to create tunnel systems at ground level. Norway rats in houses tend to stick to crawl spaces and basements.

On the other hand, roof rats are strong climbers that typically nest in trees, vines, and the upper stories of buildings, including attics and roofs.

Rats need to chew in order to keep their front teeth at a healthy size, so they are often responsible for bite marks on walls, doors, wires, and pipes. Additionally, droppings and urine, especially in kitchens or pantries, may indicate the presence of rats in houses. These pests also tend to be noisy at night, creating scratching and scampering sounds that echo through walls.

Dangers & Removal

In addition to cosmetic damage, just one rat in the house can present real dangers to residents. Chewed wires may cause electrical fires and power outages, while rodent waste carries a variety of diseases. To evade home deterioration and disease, rat prevention is key.

Residents are encouraged to caulk all crevices, keep food in airtight contains, and clean up regularly. When problems with rats in the house persist, contact the trained professionals at Orkin Canada.

Rats in Walls

The most obvious indicator of rats in the walls is rustling, clawing, and squeaking sounds. They are likely to be heard in the evenings, as the pests prepare to scavenge for food around dusk. Other signs of rat infestations include droppings, oily smudge marks along baseboards, and holes in walls and gnawing on pantry items.

Rats harbour a host of diseases, including plague, and leptospirosis. The pests’ fleas and mites are dangers as well, because they also transmit diseases to humans. Once established, rats in the wall chew on wood and wiring, causing structural damage and heightening the risk of electrical fires.

These rodents will also tear up costly insulation to pad their nests. Finally, rat feces, urine, and shed fur left between walls may cause allergic reactions.

Prevention and Control

To prevent rats in walls, homeowners should practise good trash management, keeping kitchens swept and pantry shelves free of open containers. Use metal weather stripping under doors, screen vents and soffits, and patch cracks in foundations.

For existing rat infestations, homeowners need a more proactive approach. Rodenticides and mechanical traps can be effective in some instances, but leaving control up to the professionals at Orkin Canada is the best solution.

Rats Nest

Norway and roof rats are two species common in Canadian houses. These rats live in nests either below or above ground. The animals construct their homes out of fibrous materials like paper, grass, and cloth.

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.

Rats are unable to survive Canadian winters outdoors, so it is most likely that residents will see evidence of the pest inside when cold weather hits.

When rats get into houses, they can be a headache for the people who live there. These pests may transmit several illnesses to people, including typhus and tularemia. Some of these conditions can be a direct result of rats nests. These messy piles of debris are a breeding ground for disease-carrying mites, ticks and fleas.

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.

Getting Rid of Rats Nests

Removing rats nests can be difficult and unpleasant. Not only are they located in hard-to-reach areas, but droppings and urine are prevalent around nests.

Since the pests’ waste can transmit disease, wildlife experts do not recommend removal without the proper personal protection equipment. The professionals at Orkin Canada are available to assist with rat problems.

Prevention Tips

While even the most thorough homeowners may still end up with rat infestations, implementing certain preventative measures greatly reduces the possibility of rodent problems. Keeping the home properly insulated is a crucial step to reduce points of entry for rats, while storing garbage in sealed containers makes the contents less attractive to the rodents. Homeowners should screen off windows and keep the protective coverings in good repair, as well. While a proactive approach can significantly reduce the risk of rat problems, infestations may sometimes occur regardless. Rat infestations should not be taken lightly and normally require the assistance of a pest control professional to properly resolve.

Rat Traps

Before investing time and money in rat traps, most homeowners prefer to confirm the presence of infestations. Evidence of rats includes droppings, urine, greasy marks along floors, and gnaw marks on wood and food packaging. It also helps to know the type of rat in question, as this determines where to place traps. Norway rats stay close to the ground along walls and in corners, so these are the most likely places to catch them. Roof rats, on the other hand, are agile climbers, so traps should be set high on rafters and in attics.

Glue boards are the cheapest trap option, but are frequently ineffective, since a strong rat is often able to pull itself free. When used correctly, snap traps can be very efficient. However, if the pest triggers a snap rat trap without being caught, they can learn to avoid them in the future.

Covered electronic traps are typically the most expensive and must be emptied and recharged with every catch. Live rat traps use the pests’ curiosity against them, allowing them to wiggle in without being able to back out. While humane, releasing live rats only transfers the problem to another area. Avoid the hassle and health risks associated with cleaning out rat traps by leaving removal to the specialists at Orkin Canada.


Why do I have rats?

Rats are one of the most adaptable creatures on the planet and have spread around the world. The most common rat species in Canada are the Norway rat, also known as brown rats, and the roof rat, also called black rats.

Norway rats like to stay at ground level or in burrows, in crawl spaces, basements, or around the perimeter of the house. Roof rats like to nest in trees, attics, and rafters.

Both usually access homes by squeezing through unsealed openings, but they are strong swimmers, and can enter through toilets and drain pipes too.

Rats will generally eat anything and are attracted to any food easily available. Norway rats tend to prefer foods high in fat content, like grease and meat. Meanwhile, roof rats prefer grains, nuts, seeds, and plant-based foods, possibly because the packaging can be used for nesting.

How worried should I be about rats?

Back in the 14th century, rats infamously spread the Black Death plague, which led to the deaths of millions of people. The pests do not carry the plague today, but can still transmit many other diseases, like rat-bite fever, salmonellosis, leptospirosis, and E. coli infection

These diseases can be spread directly through bites, body fluids and droppings, or indirectly by the parasitic insects, ticks and mites that feed on them or nest in their fur.

These pests also do structural damage which can be expensive to fix. Outdoors, Norway rats can leave unsightly holes in lawns and even undermine building foundations. Indoors, both species can tear up insulation, paper, and cloth to make their nests.

Rats can be heard constantly gnawing, even from behind the wall, and will leave teeth and rub marks around the home or business. Their remains and detritus can also clog up drain pipes and roof rats’ nests often block gutters.

As a business owner, rats can ruin your reputation, eliciting reactions of horror and disgust from customers, causing structural damage to your property, putting your employees at risk, and harming your ability to operate legally.

However, an infestation can grow rapidly, as rats can reproduce exponentially, giving birth to litters of up to 12 new offspring every month. To effectively deal with a rat infestation and install the traps and sanitation program needed, professional pest control services are essential.

How can I prevent rats invading?

Check wiring for chew marks and gnawing, Check the walls for rubbing marks or holes, Look out for small, pellet-like droppings, Keep food preparation areas clean, Clean up spills and crumbs immediately, Remove food sources, including bird feeders, Clean and rotate dumpsters regularly, Make sure trash cans are covered tightly, Trim back vegetation from building exterior, Seal any cracks or holes with caulk or foam, Fix leaky soda or ice machines and HVAC units, Remove any standing water outside, Don’t leave doors open for a long time, Install weather strips around doors and windows

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