Two deer mice.

Rodents, or mammals of the order Rodentia, are the largest group of mammals on Earth. Most North Americans don’t distinguish well between rodents and other pests. Furry, mischievous creatures such as raccoons and river otters are mistakenly placed in the same category as rodents. For rodent control specialists, distinguishing between rodents and other mammals is an integral part of humane pest control.


What are the characteristics of rodents?

All rodents share one universal trait that sets them apart from other pests: they have a pair of razor-sharp incisors on each jaw. The incisors are constantly growing and are kept sharp by the instinctive need of rodents to gnaw. The lower incisors wear away the soft dentin of the upper incisors to create a chisel-like tool for gnawing.

Some common features of rodents also include:

  • Large molars
  • Small body size
  • Short limbs
  • Long, strong nails
  • Unique, regenerating tails
  • Advanced sense of smell, vision, and hearing
  • Efficient metabolism

There are exceptions within the order of Rodentia to all of these characteristics. Some rodents, such as the beaver or capybara, have exceptionally large bodies. Certain kinds of rodents live underground while others live above ground. A few even live between water and land.


Which animals are rodents?

Bearing in mind that not all pests are rodents, there are still plenty of common pests that fit into the order of Rodentia.

Common Rodents


Rats have been considered a nuisance for hundreds of years. They terrorize crops and invade homes for food. Rats are well-known carriers of diseases like typhus and rabies.

However, they are very clean, affectionate, and playful. Rats can be kept as pets in North America and are a low-cost, low-maintenance alternative to traditional pets like dogs and cats. Rats will spend hours each day grooming themselves and will clean others, including human caretakers.



Mice are less ostracized than rats, but they share many of the same characteristics. The mouse shares a body shape with rats that is smaller in scale. They also sport a recognizable tail and whiskers. The hunt for food drives mice into homes more often than rats.



These large rodents are better known as river rats. They resemble rats, especially due to the length of their tails. They have webbed toes that help them swim and a characteristic soft fur that is valued by traders. Nutria are infamous for feeding and burrowing habits that destroy land, crops, and homes.


Guinea Pig

Guinea pigs are treasured in North America for their big eyes and delicate features. Like nutria, they are burrowers, but are less destructive. They average only about 2 pounds in their adulthood, making them perfect as small household pets.



Squirrels have a bushy tail and strong, short nails that help them live among trees. Their main food source comes from the branches of trees where they spend most of their time.

Rare and Wild Rodents


Beavers are hard-working, generous residents of the forests of North America. Their size is unusual in the rodent world. Most are the same size as a small dog.

Beavers are semi-aquatic with a large flattened tail, small dark eyes, small ears, and a small mouth. They have five fingered hands with strong nails for felling and transporting trees.

They are strong swimmers. A normal sized beaver can swim up to 5 mph and move underwater for up to 15 mins. They build dams across streams and make ponds and lakes where they didn’t exist before, establishing new life-sustaining wetlands.



This is the largest living rodent with a typical body weight of more than 100 pounds. It lives in the wild near lakes, rivers, and marshes. Guinea pigs share a close relation with the capybara in both behavior and genetics. Capybara, however, spend a lot of their time in or near the water.


North American Porcupine

Though it bears short limbs and strong nails like its burrowing cousins, the porcupine doesn’t burrow. It spends most of its time in the trees. Porcupines are slow movers and would make easy prey if not for their signature quills. They don’t throw their quills – when threatened, they raise them so that attackers take damage and flee when trying to make contact.


Spring Hare

It resembles a kangaroo and a hare hybrid, but is actually a rodent from Tanzania and South Africa. It shares mannerisms with the hare and kangaroo. Its movement method and posture closely mimic its marsupial and lagomorph friends.



These burrowers are better known as groundhogs. They hibernate in the winter in underground shelters and spend the rest of the year collecting food on land. Woodchucks don’t throw wood to make shelters. They throw dirt from the ground to make their underground homes. The dirt volume to make a woodchuck’s home has been estimated at 700 pounds.



This furry, large rodent is farmed all over the world for its valuable coat. Like the nutria, its fur is soft and insulating, which makes for effective protection in a range of climates.


Prairie Dog

Prairie Dogs are also burrowers whose mannerisms and diet resemble the squirrel. They are called “dogs” thanks to their unique warning call that shares pitch and intonation with a dog’s bark.


Naked Mole Rat

The naked mole rat is a hairless rodent that lives in burrows and tunnels in Africa. They live underground, so they don’t need fur. Their heads are short and wide, and their jaws are powerful.


Most rodent species are herbivores. Rodents such as squirrels, beavers, and woodchucks live on a plant diet that allows them to either hibernate in the winter or eat year-round.

Some species are omnivores, such as rats. While rats don’t try to feed on humans, they enjoy animal meat if they find it.


Wild animals that eat rodents include:


  • Cougar
  • Coyote
  • Badger
  • Fox
  • Bobcat
  • Lynx


Household pets that provide rodent control include:



Rodent control using household pets has proven to be effective as long as rodent population is not too high. Housecats are capable of removing small mouse and rat populations in homes and will chase rodents such as groundhogs that threaten lawns and gardens.