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Rat (Brown)


Rattus norvegicus
Rat (Brown)


They are found on all the continents in the world except Antarctica. They are thought to have come from Asia and spread via ships throughout the world.


They are found anywhere people live. They may have originally lived in forests and fields, but they have adapted very well to very urban habitats and in fact seem to do extremely well in their new habitats. Anywhere there is refuse (garbage) like dumps and sewers provides food and shelter to rats.

Body Traits

They have rough, dark fur, from gray to brown and are lighter underneath. They can reach 20 inches long including the tail (the tail can be as long as the body) and weigh ¾ of a pound. They have a great sense of smell.


They are active at night (nocturnal) hunting for food and bringing things back to their burrows. They dig large, complex burrows and make nests of foliage and trash. They live in groups, often near water, and are good swimmers.


They are considered omnivores and scavengers and will eat almost any organic matter.


They are eaten by cats, dogs, coyote, wild mammals, birds of prey, and man.



Females are pregnant for 3 weeks (gestation) and have about a half dozen young (though a dozen are possible!). They breed year-round, having litters every couple of months.

Lifespan and/or Conservation Status

They rarely live more than 1 year in the wild, but can live up to 4. They are listed as Lower Risk - least concern.

Rat (Brown)


Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Mammalia
Order: Rodentia
Suborder: Myomorpha
Family: Muridae
Subfamily: Murinae
Genus: Rattus
Species: Rattus norvegicus

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Amsel, Sheri. "Rat (Brown)" Exploring Nature Educational Resource ©2005-2022. May 26, 2022