Brown Rat (Rattus Norvegicus)

Rat Eradication ChesterfieldThe common brown rat also known as the Sewer rat, Norway rat, Wharf rat and Common rat. Originated from Asia, China. First recorded in Europe at the beginning of the 18th Century. Originally referred to as Norway rats because it was believed they traveled here from the East on Norwegian timber ships.


  • Adult weight: 100-500 grams.
  • Length of head and body: 200-250mm.
  • Length of tail: 150 -200mm shorter than head and body.
  • Fur, colour: This can vary, but normally brown to grey back with lighter underside.
  • Ears, hearing: Small, thick, opaque with fine hairs - Excellent sense of hearing.
  • Eyes, sight: Small, poor sight, colour blind.
  • Snout, smell and taste: Blunt. Excellent sense of smell and taste.
  • Droppings: Normally in groups, but sometimes scattered, capsule shaped.
  • Droppings size: Around 20mm long (about the size of a peanut).


The Common brown rat lives indoors, outdoors and in sewers and can burrow. Sometimes they live in their burrows. They are excellent jumpers, climbers and swimmers and can easily squeeze through very small openings. They will take every opportunity to gain access to our environment whether it be domestic premises, factories, institutions or farms. The brown rat must drink water daily, unless its food source is extremely moist. Their behaviour is somewhat predictable in taking a set path and in doing so they create runs which can be a good indication of their presence.

Despite their eagerness to exploit new locations freely they have a tendency to avoid new objects for several days, i.e. baits placed on their runs. This is known as Neophobia - New Object Reaction The Brown rat has a range of between 50 and 100 meters


Rats are omniverous, but prefer to eat cereals wherever possible. They will however eat just about anything including meat. Where no water is available their diet needs to be of a moist nature. On average they will consume up to 30 grams of food each day about one tenth of their body weight.


Rats breed quickly. On average the female rat can produce up to five litters a year, each litter having between 8 - 10 young, these would reach sexual maturity in 8-12 weeks. Further mating is possible almost immediately after the birth of the litter. With this in mind it is essential that known problems with rats are dealt with speedily.

Life Cycle

  • Life span: 9-18 months
  • Sexual maturity: 8-12 weeks
  • Litter size: 8-10 offspring
  • Reproduction rate: 7 litters per year

Reason for control

There is little doubt that rats are detested by most people. It is common knowledge that they spread disease, contaminate foodstuff and cause serious damage to buildings and materials. Their capability to carry serious disease is without doubt the reason why we most fear them. When we think of rats and disease our first thoughts are usually of the plague but this is no longer an hazard. Rats do however, still carry very serious diseases which can be potentially fatal to humans and other animals, i.e. Weill's disease and murine typhus, as well such organisms as Salmonella bacteria, parasites, viruses and worms.

Rats, like mice continually gnaw on solid objects. Rat damage in buildings can prove very costly. Fires can cause hundreds of thousands of pounds worth of damage where cables and wires are gnawed. Gas and water pipes are also at risk. Continual rat burrowing can cause serious subsidence to buildings.

All in all, rats are a real threat to our environment and must be controlled!

Control measures

Because of the risk that rats pose we can offer little advice on self control measures. If rats are on your property either inside or outside you should seek professional help immediately. Such problems need to be dealt with quickly by someone professionally qualified in pest control.

Rat Problems Dronfield
Dead rat in kitchen unit

Created by DS Creative