In Rats, Mouse, News

Mice and rats are among the most common and problematic pests in Quebec. Although they share many similarities, these rodents also have important differences, meaning that their behavior and potential impact on your home will vary.

Montreal exterminators explain the differences between mice and rats so that you can make good choices if faced with an infestation. Regardless of the type of rodent that is bothering you, get all the information you need to protect your home and your health.

What are the physical differences between rats and mice?

Mice and rats are both species of rodents found in Québec, but they have some notable physical differences. Here’s how to tell the two apart.


The first difference is size: mice are significantly smaller than rats. Mice are on average 7.5 to 10 cm long, while rats can be up to 25 cm long. Mice also have thinner tails than rats; a rat’s tail is thicker and shorter relative to its body size.

Ears and nose

Mice have larger ears relative to their body than rats, which have smaller, rounded ears. A mouse also has a pointed nose, while a rat’s nose will be wider and more rounded. These physical differences can be helpful in telling them apart. If you suspect a rat or mouse has entered your home, contact professionals as soon as possible to avoid an infestation!


Rats and mice can display a variety of coat colours and textures, depending on the species. This can make identification difficult. In general, mice have smoother fur than rats, whose fur is often disheveled.

difference between mouse and rat

Differences in behavior

If you want to get rid of rodents in your home, here are some behavioral differences that can help you tell whether you are dealing with rats or mice.


Rats and mice have different personalities. Mice are generally curious, while rats are cautious, partly because due to their high intelligence. A mouse will naturally approach any object placed in front of it. With mice, it is possible to place a trap directly in their path to goad them into it. Rats, on the other hand, will avoid something in their way. To trap a rat, you need to put unarmed traps in the area until they get used to them, then replace them with “armed” traps.

Eating habits

Rats have a varied omnivorous diet, and prefer foods high in fat, protein and carbohydrates including grains, fruits, vegetables, meat, cheese and nuts. Rats may also eat pet food. Mice, on the other hand, are primarily herbivorous. Mice eat seeds, nuts, fruits, and vegetables, and also insects and some pet food in small amounts.


Rats have a longer gestation period than mice. On average, gestation in rats lasts 21 to 23 days, while mice gestate only 19 to 21 days.

When it comes to offspring, rats generally have smaller litters than mice. Rats can have 6 to 12 pups in a litter, while mice can have up to 14 or more.

Mice breed more frequently than rats. Mice can breed year-round, with a short gestation period and early sexual maturity, which means they can give birth to several litters in a single year. Rats, on the other hand, have a less frequent breeding season and usually have a litter roughly once a month.


It is common to become aware of an infestation by hearing movement. The type of activity can be a good way to identify the type of rodent. Mice are fast runners and excellent jumpers, swimmers and climbers. If you hear a fast scurrying sound, it is likely a mouse. Since rats are larger and heavier, they usually make more noise. Rats also tend to stick to regular routines and routes – a rodent that always follows the same path and has some sort of routine is often a rat.

Behaviour near water

The attitude of rodents toward water is key, because while both mice and rats obviously need to drink, rats prefer wet environments and enjoy swimming. If your home is located near a stream or reservoir, then it is reasonable to assume that rats are the prime suspects in the event of an infestation. Rats are also known to burrow under buildings, while mice will rarely burrow.

Disease transmission

Both rats and mice can transmit diseases to humans.

Rats are known to transmit diseases such as leptospirosis, hemorrhagic fever renal syndrome (HFRS) and salmonellosis. These diseases can be transmitted to humans through contact with rat feces, urine or saliva, or through rat fleas.

Mice can also pose a danger by transmitting respiratory diseases including mouse fever, lymphocytic choriomeningitis (LCM) and hantavirus. These diseases can be transmitted by contact with feces, urine or by inhaling airborne viral particles.

Keep rodents out of your home with Elite Pest Management

Distinguishing rats from mice is essential for implementing effective rodent control. In addition to physical and behavioral differences, pest control companies take into account feeding and breeding habits, making it possible to develop optimal treatment methods.

If you suspect there are rats or mice in your home or business, act quickly to avoid a larger infestation. At Elite Pest Control, we specialize in pest control and can help you identify and eliminate rodents safely and effectively.

Our experienced team uses environmentally friendly pest control methods to secure your family and home. We also offer preventive pest control programs to prevent future infestation.

Contact us today to learn more about our services and to get a free quote.

Pascal Rock
Pascal Rock  
Director, Elite Pest Control
Founder and mainstay of Elite Pest Control, Pascal Rock has embodied expertise and dedication for over a decade. His training, acquired with expert mentors in extermination and pest decontamination, has shaped an outstanding professional. Under his leadership, a team of six seasoned technicians deploys the very best pest control strategies. Together, they ensure the peace of mind and safety of residents and professionals from Montreal to Quebec City, by offering fast, effective interventions, available at all times.