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black rat compared to brown rat

What Is The Difference Between Black Rats And Brown Rats?

(Last Updated On: June 4, 2022)

Most people find it difficult to distinguish between black and brown rats, but they’re distinct in their physical appearance, history, and characteristics.

The brown rat has a short tail relative to its body size, while black rats have very long tails. Brown rats have significantly lighter underbellies than black rats, and their ears are smaller.

Also, black rats look smaller than brown rats, which have characteristically plump shapes.

Brown rats hail from Central Asia, while black rats originated from India. Both types can be found worldwide, although they’ve traveled via different means.

The black rat (ship rat) prefers to live in roofs or high areas in tropical regions, while the brown rat (Norway rat) is more contented in colder climates.

Are Brown And Black Rats Different?

Black and brown rats may appear interchangeable, with their only difference being their fur color. However, they have different appearances, temperaments, and origins.

Here is a quick overview of what sets brown and black rats apart:

Brown RatsBlack Rats
Forage in the same placesAvoid returning to places they’ve eaten.
Have small fur-covered earsLarge and thin ears
Found across the worldTropical and coastal areas  
Tails shorter than their bodiesLonger tails than bodies
Eat almost anythingEat almost anything
Thicker bodiesSlender bodies
Nocturnal and diurnalNocturnal
Superb swimmersExcellent climbers

Brown Rat (Norway Rat)

Although they’re known as rattus norvegicus or the Norway rat, the brown rat didn’t originate from Norway. The brown rat hails from Central Asia.

It’s the most common type of rat and has been domesticated as a pet.

Brown rats are large, and their bodies are covered in dense fur, except for their:

  • Ears
  • Tail
  • Nose
  • Underside

The fur is normally grey or dark brown, but it can be a lighter shade of black in some rats. However, the legs and underside of brown rats are lighter than the rest of the body, usually a pale grey.

Some brown rats are energetic enough to swim for miles at a time, which further explains why they’re so common in most urban areas.

Norway rats are quite large, with their lengths anywhere from 8-10 inches. Even though their tails look small relative to their bodies, they have an average length of 7-10 inches.

Adult males weigh 12 ounces, while the average weight for females is about 9 ounces. However, brown rats can exceed these sizes in a domestic setting and weigh up to 25 ounces.

what do brown rats look like?

How The Brown Rat Got Its Names

The brown rat has been around for centuries, if not millennia.

It first appeared in Europe in the 1300s. During this time, it earned many names. The following is a complete list of colloquial names for the brown rat and those names’ origins:

Norway Rat (Rattus Norvegicus)

This name came about hundreds of years ago. Many people believe they spread to England, and subsequently Europe, from Norwegian ships.

Common Rat

In 17th and 18th century Europe, the brown rat was prevalent in urban areas.

Sewer Rat

This name originated because brown rats are gifted swimmers, thriving in wet areas, including sewer pipes.

Street Rat

The brown rat was commonly seen hiding in roadside sewers, garbage bins, and bushes.

Parisian Rat

By the 1800s, the brown rat had infested most of Europe.

During the Siege of Paris (1870), starvation became so widespread that many Parisians started hunting rats for food. The rat became synonymous with the city, albeit for only a short time.

Water Rat

This name arose from the brown rat’s ability to swim. It’s also because brown rats used to live in areas near water bodies, particularly oceans.

Wharf Rat

Wharves are areas where ships dock and load/unload cargo and passengers into ports. Brown rats were prominently seen in and around these areas, hence their association.

Hanover Rat

Most of the names associated with brown rats originated from 17th-century English culture. The Hanovers were a British royal family with German heritage who ruled between 1714 and 1831.

They were so despised that people came to associate most problems in the country with them. The brown rat, which caused many problems, was naturally associated with the ruling family.

Where Are Brown Rats Found?

Norway rats are primarily found in wet areas such as sewer lines, urban waterways, and kitchens. However, they’re now found in most urban areas and farmlands due to environmental changes.

Problems with Brown Rats

There’s no indication that brown rats cause more problems than other rats. However, because they’re found across the entire world, they’re a bigger threat.

Aside from being a nuisance, brown rats can cause serious health and structural damage, including:

Diseases

Brown rats are known to transmit other common diseases like:

  • Bubonic plague
  • Toxoplasmosis
  • Hantavirus
  • Typhoid
  • Salmonella

These are contracted through inhalation or ingestion of dried particles from rat urine, feces, or saliva.

Some brown rats are active carriers of rabies and rat-bite fever.

Damage

Brown rats are rabid feeders. Once they get inside your home and kitchen, expect to find ruined ingredients, gnawed-on furniture, and destroyed wiring.

Black Rat (House Rat)

Rattus rattus, or black rats, aren’t synonymous with any country. They’re believed to have originated from India, moving across the world through ancient trade ships, so most people call them ship rats.

Black rats are slightly smaller than brown rats, with their body lengths ranging between 6-8 inches. Their ears are large relative to their face size, and they have noticeably large whiskers on their muzzles.

Their tails are almost always longer than their bodies, typically measuring 7 inches or more. The long tail provides balance when the rats climb to and from their mostly arboreal habitats.

Despite the name, most black rats are not completely black but grey-brown or a mixture of grey, black, and agouti. They have lighter colored underparts and legs, just like brown rats.

Black rats will have finer coats, while Norway rats have thicker coats.

Overall, the house rat is more slender than the Norway rat. They weigh between 2-9 ounces, depending on their gender and subspecies.

Some attribute this low average body weight to the fact that black rats are predominantly herbivorous, although they’re scientifically categorized as omnivores.

Black rats largely feed on crops, from fruits to cereals to grains. They only feed on insects and other invertebrates in certain circumstances.

House rats are nocturnal animals, although they easily adapt to their habitat. They arise at dusk (often in groups) and eat as much as they can within a short time.

If they can’t quickly finish their food, they’ll carry as much as possible to their nest, which is why many farmers consider them more destructive than brown rats.

what do black rats look like?

How The Black Rat Got Its Names

Since the black rat is the more common pest, this reflects its names:

Ship Rat

During the 1400s, in a period known as the Age of European Exploration, the black rat once hid in ships. These vessels transported explorers and cargo from Europe to the rest of the world.

People in Asia, Africa, and the Americas thus came to know this rodent as the ship rat.

Roof Rat

The black rat is a very good climber and likes living in rooftops.

House Rat

The black rat thrives in warmer climates and rural areas, which compose the majority of human settlements. This, coupled with its predominantly crop-based diet, is why it’s mostly found in or near human houses and grain storage units.

Rattus Rattus

This is the species’ scientific name, as put forward by the Swedish scientist Carl Linnaeus in 1758. It translates literally to “rat rat” in Medieval Latin.

Where Are Black Rats Found?

House rats are found in warm, tropical environments. However, according to PLOS One, they’re increasingly adapting to life in colder environments.

Unlike their brown rats, black rats are poor swimmers. You’ll rarely find them near water bodies or sewer lines. They prefer to live in elevated places, such as rooftops and on the top floors of buildings.

Black rats are good at climbing surfaces and can comfortably scale a 50-foot tree in seconds.