Rattus rattus

List of Fact Sheets | Glossary

Search | Back Home

Family

Rodent

Genus

Rattus

Species

rattus

Common name/s

Black Rat, Roof Rat

Distinguishing Features

Body size is about 8cm in length. The upper body colouring is brown, black or charcoal grey, with a cream or white underbelly. The tail is scaly and long relative to its body size.  Front teeth are chisel shaped.

Similar Species

The Australian native Bush Rat (Rattus fuscipes ) and the Agile Antechinus (Antechinus agilis ).

Distribution

This species is found widely across Australia, especially in the coastal regions in human modified areas. It is also found commonly in and around human settlements where food and shelter is readily available in most countries of the world.

Country of Origin

Europe

Survey Techniques

Trapping

Conservation (Pet/Pest) Status - National

Common.

Conservation (Pet/Pest) Status - Regional

Common

LSCCES Population

Common

Associated vegetation community

In their natural environment Black Rats are common to woodlands, forests and grasslands. They are typically associated with human settlements, including cities, rural villages and farms.

Limiting Resources

Black Rats are very adaptable and can live in a variety of places such as roofs, cavity walls, trees, scrapes or burrows around farms. A close distance to humans usually ensures the food and water requirements of this species are met.

Breeding

A mature female rat can give birth to about 20 young in a year (4 to 6 at a time). Young are born in nests made from paper, rubbish, plastics, grass or other material. They become completely independent and able to reproduce after three months. Outdoor populations in the natural environment tend to peak in summer or early autumn, while indoor populations remain constant throughout the year.

Behaviour

Black Rats are very good swimmers and climbers, meaning they can access most areas to feed, shelter and breed. Usually they move about 50m from their nest site. They will climb trees to steal eggs out of birds' nests or to eat fruit. They are known to cause trouble by gnawing at pipes and electrical cords. Rats have very poor vision, relying on their keen sense of smell, acute hearing and their whiskers and sense of touch. They spend time around water bodies and beaches and are the most commonly seen rodent in public parks and beaches.

Functional Group

Omnivore

Food Species

In the wild, Black Rats will eat a range of fresh plant material, nuts and seeds, fruit and vegetables and tree bark. In human environments they are known to eat almost anything.

Predators

Feral or domestic Cats (Felis catus ) and Dogs (Canis familiaris), snakes, birds of prey, and other rats will all attack and kill Black Rats

Interesting Fact

If the mother rat has become wary of rodenticides or traps, many of her young will learn to avoid them. This learning experience can make management difficult in sites where long-term rodent suppression programs have been unsuccessful in the past.