The common rat typically has brownish fur on its back and it grey underneath. The adult body length is 200-270mm, plus a tail length of 150-200mm. Rats have excellent senses of smell and taste. They have an acute sense of hearing, frequently using ultrasound to communicate, and are particularily sensitive to any sudden noise.
Common rats live in any situation that provides food, water and shelter. In homes, they will live in roof spaces, wall cavities or under floorboards. In gardens, they will burrow into compost heaps and grassy banks or under sheds. Rats are often found living in sewer systems; they are agile climbers and excellent swimmers.
Preferred foods are cereal products, although rats and omnivorous and will eat almost anything that humans eat. Most damage caused by rats is through gnawing and ripping open packets of food. They also spoil and contaminate food with urine, droppings and hairs. Unlike mice, rats require water every day.
Rats are particularly active at night, but may be seen during the day searching for food, water or shelter. Common rat droppings are capsule-shaped, black and up to 12mm long. A rat will leave up to 40 droppings a day.
Rats follow the same routes when moving around and often leave trails through grass and low vegetation.
Rats can build complex tunnel systems, which often extend deep into the ground. Entrance holes 70-120mm in diameter will be seen in grassy banks, under tree roots and at the edge of paving, drain cover surrounds or wall-floor junctions. Sometimes nests can be found indoors, in lofts or under floorboards.
Rats gnaw continually to wear down their front teeth, even on non-food materials such as electrical cables, pipe work and wooded fixtures.
Rats can transmit many diseases to humans, including Salmonallosis (food poisoning) and Weils disease, usually from the urine of infected rats. Rats may also cause considerable damage to buildings, foundations and other structures due to gnawing and burrowing.
To prevent rat infestation householders can take a number of simple precautions:
- Keep your home in good repair; rats only need a gap 15mm to gain entry.
- Remove potential nesting sites by keeping yards and gardens clean and tidy, and by cutting back overgrown areas.
- Ensure that drain inspection covers are in place and are in good repair.
- Seal gaps around heating and water pipes.
- Ventilation bricks and slots should already have a fine wire mesh incorporated. If this is worn replace it externally with 3.15mm insect mesh.
- Do not leave household waste where rats can get access to it, close dustbin lids and composters and do not feed wild birds in excess – you may be feeding rats as well.
Clear Round Pest Services has effective treatments for rats in all situations using rodenticides and/or traditional methods after a thorough survey of the affected area.