Black Rat (Rattus rattus)
Image: Lina Frigo
Source: Museum Victoria
Question: What’s the difference between a black rat and a brown rat? Do we have them both in Australia?
Answer: Rattus rattus (common name: the Black or Roof Rat) and Rattus norvegicus (the Brown or Norway Rat) are both introduced species of rat, and are widespread throughout the country and the world. We do have both species in Victoria!
There are several ways to differentiate the two species. The Black Rat is generally smaller and lighter in build than the Brown Rat, with a longer tail compared with its body size, and a more pointed nose. The Brown Rat, by comparison, tends to have smaller ears and eyes, and a blunter nose. However, the age of the specimen can confuse the issue, with juveniles of both species tending to have larger eyes and ears proportionally.
Despite the common names, colour is irrelevant; Black and Brown are names only and individuals are highly variable. Patches of white and/or grey are not unique to either species (although generally, the young of both are paler than adults).
Don’t forget, the Discovery Centre offers a free identification service. If you have a photograph of an unknown rat and would like it identified, check the links on the side of this page to access our services.