The common brown rat typically has brownish fur on its back and grey underneath, but its colour can vary from white through to black. Common rats live in any habitat that provides food, water and shelter. In homes they live in loft spaces, wall cavities, cellars or under floorboards; whilst in gardens, they will burrow into compost heaps and grassy banks or under sheds. They are also commonly found in sewer systems.
Rats transmit many diseases to humans, including food poisoning (salmonella) and bubonic plague. Rats are adaptable and highly mobile. Once signs of an infestation are found, immediate action should be taken to get rid of them.