10 Largest Rodents In The World (They Are Massive!)

  • 11 min read
  • List, Rodents

While I was writing about the world’s largest rodent capybara, I wanted to learn about the other biggest rodents in the world.

Read on to find out if that rat from your backyard made a list!

Common nameScientific nameMax body mass kg (lb)
1. CapybaraHydrochoerus hydrochaeris91.2 kg (201 lb)
2. North American beaverCastor canadensis50 kg (110 lb)
3. Lesser CapybaraHydrochoerus isthmius45.4 kg (100 lb)
4. Eurasian beaverCastor fiber40 kg (88 lb)
5. Cape porcupineHystrix africaeaustralis30 kg (66 lb)
6. Crested porcupineHystrix cristata27 kg (60 lb)
7. North American porcupineErethizon dorsatum18 kg (40 lb)
8. Indian crested porcupineHystrix indica18 kg (40 lb)
9. CoypuMyocastor coypus17 kg (37 lb)
10. Patagonian maraDolichotis patagonum16 kg (35 lb)
Information for the table pulled off Wikipedia

Josephoartigasia Monesi – Biggest Extinct Rodent

Josephoartigasia monesi is the largest rodent known that lived approximately 4 to 2 million years ago during the Pliocene to early Pleistocene. Its almost complete skull was discovered in 1987 on the coast of Río de la Plata in Uruguay but scientifically described only in 2008.

Josephoartigasia monesi was named after national hero of Uruguay José Gervasio Artigas and the paleontologist Álvaro Mones.

By comparing the skull with various existing species of rodents, researchers estimated the body length at 3 m (10 ft), with a height of 1.5 m (5 ft) and a median weight of 900 kg (2,000 lb).

1. Capybara

The largest rodent is all Netflix & chill
The largest rodent is all Netflix & chill.

My absolute favorite animal is the capybara (don’t tell my cats). Capybara is the biggest living rodent weighing in at 35 to 66 kg (77 to 146 lb), with an average of 48.9 kg (108 lb). Compare that to your guinea pig!

Capybaras can grow from 106 to 134 cm (3.48 to 4.40 ft) in length, stand 50 to 62 cm (20 to 24 in) tall. Its scientific name, Hydrochoerus hydrochaeris, comes from Greek and means water pig – how fitting!

Capybaras are semiaquatic mammals found throughout almost all countries of South America except Chile. They live near water in dense forests and savannas.

They are exceptional swimmers and can hold their breath underwater for up to five minutes at a time. No wonder conquistadors thought they were fish!

RELATED: Do People Eat Capybaras?

Capybaras do not like to be alone, and that’s why they live in groups of up to 100 individuals but mostly in smaller groups of 10-20. This helps them to keep them safe from predators like anacondas, jaguars, pumas, ocelots, eagles, and caimans. Yikes! Poor capys.

They are strict herbivores that graze most of the day and eat other food, like fruit, tree bark, and aquatic plants. Capybaras are also known to be picky eaters to the point where they would feed on the leaves of one species of plants or grass and disregard other species surrounding it.

RELATED: What Do Capybaras Eat?

2. North American beaver

The North American beaver is the world’s second-largest rodent after the capybara. Adult beavers weighing over 25 kg (55 lb) are not uncommon, with their max body mass coming in at 50 kg (110 lb). They are super strong and great swimmers. Beavers are known for building dams, canals, and their homes; lodges. The North American beaver is an official animal symbol of Canada.

Like the capybara, the beaver is semiaquatic and has a large, flat, paddle-shaped tail and large, webbed hind feet. They use the tail both to signal danger by slapping the water’s surface and as a location for fat storage.

Beavers are active mainly at night. They are excellent swimmers and may remain submerged for up to 15 minutes.

Beavers are herbivores, and they consume a mix of herbaceous and woody plants. Some of their favorite foods include water lily tubers, clover, apples, leaves, and cambium from Aspen or other fast-growing trees.

Find out more about that in Do Beavers Really Eat Wood?

Similar to capybaras, in the 17th century, the Roman Catholic Church ruled that beavers were fish so they could continue to be eaten on Lent.

3. Lesser capybara

Lesser capybara

Poor lesser capybara. First, it was described as a species in 1912 but later demoted to a subspecies of the capybara. Then again, in the mid-1980s and 90s, it got its status back, but it still has haters thinking it’s a subspecies. Even its name is a slap in the face. Will it ever step out of the shadow?

The lesser capybara closely resembles the capybara and is common in Panama but rare in Venezuela. Luckily for them because capybara meat is considered to be a delicacy in Venezuela.

Not much is known about our lesser capybara friend, unfortunately. Sometimes it’s better for an animal not to be in the spotlight, I guess.

RELATED: 8 Unusual Facts About Capybara Teeth

4. Eurasian beaver

Our European beaver counterpart was hunted to near-extinction at the turn of the 20th century. There were only about 1,200 beavers left in Europe and Asia due to hunting for fur and castoreum. Since then, it made its grand comeback and now resides from Spain to Mongolia. What a Phoenix!

If you’re wondering what castoreum is, it’s used by the beavers to grease their fur and to mark their territory with an individual beaver’s scent. Beavers have castor sacs between their genitals and their anus that produces this liquid substance.

After killing the unfortunate beaver, the castor sacs can be removed and dried. From the dried castor sacs, castoreum can be extracted and used in various products, from perfume to cigarettes. Ugh! In the EU, it is illegal to hunt beavers, so most of the castoreum comes from the US and Canada.

There are several important differences between American and European beavers, the main one being that the North American beaver has 40 chromosomes, while the Eurasian beaver has 48. The two are not genetically compatible, and after more than 27 attempts in Russia to hybridize the two species, they failed.

5. Cape porcupine

Cape porcupines or South African porcupines are the largest rodents in Africa and also the world’s largest porcupines and, dare I say, the cutest.

They are heavily built animals, with stocky bodies, short limbs, and an inconspicuous tail. The body is covered in long spines up to 50 centimeters (20 in) in length, interspersed with thicker, sharply pointed, defense quills up to 30 centimeters (12 in) long, and with bristly, blackish, or brownish fur.

Cape porcupine weighs from 10 to 24 kilograms (22 to 53 lb), with exceptionally large specimens weighing up to 30 kg (66 lb).

When attacked, the porcupine freezes. If cornered, it turns vicious and charges for stabbing its attacker with its quills. Otherwise, the porcupine may retreat into its burrow, exposing only its quills and making it hard to dislodge.

RELATED: Do People Eat Porcupines? (Can You Even Eat Them??)

Cape porcupines are found across the whole of southern and central Africa, to south Kenya, Uganda, and Congo. They are often considered pests by local farmers because they can feed on crops and damage trees.

Unlike most rodents, Cape porcupines are long-lived, surviving for ten years in the wild or up to twenty years in captivity, and their diet consists mostly of plant material: fruits, roots, tubers, bulbs, and bark.

6. Crested porcupine

African Crested Porcupine
African Crested Porcupine

Next on our list of the largest rodents in the world is the crested porcupine. This porcupine is a bit smaller than its cousin, the Cape porcupine. It is also known as the African crested porcupine and is found in Italy, North Africa, and sub-Saharan Africa.

The adult crested porcupine has an average head and body length of around 60 to 83 cm (24 to 33 in) long, discounting the tail, and weighs from 13 to 27 kg (29 to 60 lb).

RELATED: Cute Baby Porcupines (Porcupettes) Guide With Facts, Photos, And Videos

It is called crested porcupine because of the quills that run along the head, neck, and back that can be raised into a crest.

The crested porcupine, same as other porcupines, is, for the most part, herbivorous, eating roots, bulbs, and leaves, but occasionally they do consume insects, small vertebrates, and carrion.

Porcupines are killed for their quills, which are used as ornaments and talismans. In North Africa, they are killed and sold to be used in traditional medicine. In some areas, farmers illegally use poison to kill them.

7. North American porcupine

The North American porcupine is also known as the Canadian porcupine or common porcupine. Amazingly, its ancestors rafted across the Atlantic from Africa to Brazil over 40 million years ago and then migrated to North America. Talk about a feat!

That is not the only amazing fact about the North American porcupine. The porcupine is the only native North American mammal with antibiotics in its skin.

Those antibiotics prevent infection when a porcupine falls out of a tree and is stuck with its own quills upon hitting the ground. Funny enough, porcupines fall out of trees fairly often because the succulent buds and twigs highly tempt them at the ends of the branches.

Porcupine quills aren’t just a painful deterrent, they’re deadly daggers, and porcupines are not afraid to use them. Porcupines have been known to injure lions, leopards, hyenas, even humans.

An adult porcupine has about 30,000 quills covering all of its body except its underbelly, face, and feet. They are used primarily for defense but also serve to insulate their bodies during winter.

Our Canadian porcupine is also a smelly cat; it has a strong odor to warn away predators, which can increase when agitated. The smell has been described as similar to strong human body odor, goats, or some cheeses. Mmmm, cheese.

8. Indian crested porcupine

The Indian crested porcupine or Indian porcupine is native to southern Asia and the Middle East. The Indian crested porcupines weigh from 11–18 kg (24-39 lb). Their body (from the nose to the base of the tail) measures between 70–90 cm (27-35 in), with the tail adding an additional 8–10 cm (3-4 in).

Due to their flexible environmental limits, Indian crested porcupines occupy a broad range of habitats. They prefer rocky hillsides but are also common in tropical and temperate shrublands, grasslands, forests, plantations, and gardens.

Interestingly, they tend to avoid moonlight in the winter months, which could be a strategy to evade predators. Predators of the Indian crested porcupine include large cats, caracals, wolves, striped hyenas, Asian wild dogs, saltwater crocodiles, and of course, humans.

The word “porcupine” comes from the middle or old French word porcespin, which means thorn pig.

9. Coypu

The coypu is also known as the nutria and lives in burrows alongside stretches of water and feeds on river plant stems.

Originally native to subtropical and temperate South America, it has been introduced to North America, Europe, Asia, and Africa, primarily by fur farmers. It is now considered to be a pest and invasive species.

Top 10 Largest Rodents in The World Infographic
Top 10 Largest Rodents in The World Infographic

Their burrowing can cause extensive harm to river banks and flood defenses. They also destroy root crops and eat bird eggs.

After coypu was introduced in Britain in 1929 to be farmed for fur, they subsequently made their way into the wild, and the total eradication took 11 years of concerted effort costing millions of Pounds.

The coypu somewhat resembles a very large rat or a beaver with a small tail. Adults are typically 4–9 kg (8.8–19.8 lb) in weight and 40–60 cm (16–24 in) in body length, with a 30 to 45 cm (12 to 18 in) tail. Coypu can weigh up to 17 kg (37 lb).

10. Patagonian mara

Patagonian Mara
Patagonian Mara

By far the cutest rodent on our largest rodents in the world list is the Patagonian mara or the Patagonian cavy, Patagonian hare, or dillaby. This herbivorous, somewhat rabbit-like animal is found in open and semiopen habitats in Argentina, including large parts of Patagonia.

It has distinctive long ears and long limbs. The average Patagonian mara has a head and body length of 69–75 cm (27–30 in) with a tail of 4–5 cm (1.6–2.0 in). It weighs 8–16 kg (18–35 lb).

Patagonian maras are found only in Argentina, from 28 to 50°S, and they prefer to live in habitats with shrub cover, but they also inhabit overgrazed and barren soils in the Monte Desert biome.

RELATED: Boop! These Are The Cutest Rodents In The World

Maras are primarily herbivorous. They feed on green vegetation and fruit. They are monogamous, and pairs of maras stay together for life, with the replacement of partners only occurring after one’s death. Awww.

That’s it, that was the list of the largest rodents in the world plus one extinct super rodent.

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Adrian Volenik

I've lived around animals my whole life and I hold a Diploma in Animal Physiology. When I'm not reading or writing about wild animals, health and fitness, and technology, you can find me playing with my son and two cats. My pastimes include running, playing video games, and solving the NY Times crossword.