Description

Rats will invade buildings in search of food and shelter. They may transmit disease, soil and destroy materials and damage buildings. The Brown rat (Rattus norvegicus) is commonly found throughout Britain.

Life cycle

Young rats reach maturity in two to three months; they average four-seven litters a year, with 8-12 pups per litter. They live in colonies.

The Brown rat prefers to live underground in tunnels, usually in sewers and will venture above ground in search of food, water and nesting materials.

They move quickly and are excellent climbers and active burrowers. They eat about 10% of their body weight daily and require a regular supply of water.

Rats need to gnaw to keep their incisor teeth worn down as these grow constantly and therefore create a lot of damage to the fabric of a building especially in woodwork.

Rats use 'runs' from one place to another. This route becomes soiled with grease and dirt from their fur and they constantly leave droppings which are banana or sausage shaped. The amount of droppings can indicate the size and duration of the infestation.

Appearance

The Brown rat or sewer rat is brownish grey in colour. Its body is about 200-270mm in length and is large and thickset. The nose is blunt, it has small eyes and the ears are short, thick and finely haired. The fur is shaggy and coarse. The tail is shorter than the head and body and is about 165-205mm long.

Control methods

Removal of food, water and harbourages will deny rats their main requirements for survival.

Traps can be used but poison baits are the most effective method of control.

Multiple dose poisons with delayed action are used by the Pest Control Team. Rats return to their nests to die and if these nests are in warm areas of houses and buildings an offensive odour may become apparent which can last up to 14 days.