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Evidence of rats

Black staining caused by fur rubbing on surfaces, droppings and gnaw marks. Rat droppings are larger than mouse droppings and may be in groups.


Blocking openings to the home can prevent rats becoming established. So check air bricks are intact and check for access points around gas, electricity and water pipes. Check that doors fit tightly as this will help prevent rats entering and limit their movement between properties. Keeping the home clean, storing food in sealed containers and emptying bins regularly will reduce the chance of rats staying in your home and breeding.


There are two ways to treat rat infestation: by trapping or poisoning. Rats can communicate their aversion to poisonous foods so unless all rats are targeted at once, it can be difficult to treat the infestation successfully. Traps should be placed where pets and children cannot touch them and should be checked regularly.

More about rats

The Brown Rat is the most common species in the UK; the Black Rat is rare and is confined to a few port towns and islands. Rats live in refuse tips, under floors, in cavity walls of buildings, sewers, bin stores and gardens. They often move into buildings in autumn and winter in search of shelter and food but may stay if there is an all-year-round food source. They are mainly active just before dawn and after dusk and tend to move along hedgerows, walls and river banks at ground level (although they can climb and jump).

Rats contaminate food and surfaces by leaving urine, droppings and hair. Rats can carry infectious diseases such as Leptospirosis (Weil's disease), Toxoplasmosis and Salmonella, so it is important to treat infestations as soon as possible.

Rat holes or burrows are 6 to 9cm in diameter and tend to be in undisturbed areas near food. Runs are typically 5 to 10cm wide and look well-used. Greasy smear marks may be seen where rats make contact with stone, wood and metal, such as on steps and in cupboard floors. Droppings are 15-20mm long, cylindrical, flat at one end and often pointed at the other. Droppings are moist when fresh, but dry within hours to give a dull appearance.


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