
Details
Brown rat
Rattus norvegicus
- Size
- 32–50 cm · 150–500 g
- Diet
- Omnivore
- Activity
- Nocturnal
- Sociality
- Herd
- Lifespan
- —
A large rat established around cities and waterways, with a sturdy body, relatively short tail, and small ears.

Details
Rattus norvegicus
A large rat established around cities and waterways, with a sturdy body, relatively short tail, and small ears.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
Found in towns, farms, riversides, ports, sewers, and coasts, especially where damp cover and human food are available.
Fur is brown to gray-brown, the scaly tail is shorter than head and body, and the ears are relatively small. The body is robust.
Mostly nocturnal, it uses burrows and building cavities as bases for group living. It is wary and follows repeated runways.
Grain, fruit, meat, fish, eggs, and refuse are eaten; near water it also takes mollusks and small animals.
Large litters are born in hidden nests, and breeding can continue year-round where food is abundant. Young mature quickly.
Globally low-risk; introduced populations are important targets for sanitation, crop protection, and island conservation.