Best time to see: all year
Key facts
A serious pest, destroying food and property and carrying diseases
Adaptable and fecund, but prefers damp areas including sewers
Widespread across Europe except around the Mediterranean, where it is replaced by the black rat
Recognition
Usually dark brown fur with a greasy appearance, and with a long, scaly tail
Length up to 50cm including tail; weight up to 600g
Eats almost anything, sampling new foods and waiting a day or so to find out if it's harmful
Lifecycle
Nests in grass, paper or similar material, in a hole or burrow
Produces up to 5 litters a year, usually of 7–8 young, and at any time of the year
© Leslie Borg