Rats

Biology and Behaviour

Rats are a hazard to public health. They can transmit a number of diseases which can be potentially fatal to man, such as Weil's disease and murine typhus. They also carry disease organisms such as Salmonella bacteria, viruses and parasites such as worms and fleas.

In an urban environment rats readily find food from a variety of sources such as refuse, drains and sewers.

Rats will burrow, especially into soil, compost heaps, under coverings such as paved areas and under sheds. Gas and water pipes are also at risk and rat burrowing can undermine building foundations. They can be frequently found living inside buildings in the cavity between walls and in roof spaces; or beneath piles of rubbish, near water, or in drains and sewers. Due to their agility and ability to squeeze through small openings it is sometimes difficult to keep rats out of buildings without some form of rodent proofing being carried out.

Rats continually gnaw and they have very hard incisor teeth which can penetrate materials such as concrete, lead and aluminium. This can result in expensive damage and even fires when electric cables are damaged.

They can breed quickly; a healthy female can produce five litters a year, each of 8 - 10 young with offspring attaining sexual maturity in 8 - 12 weeks. At any time as many as 30% of females in a population may be pregnant.

It is quite easy for infestations to build up without ever noticing a rat - their nocturnal habit tends to keep them away from the human contact. If a rat is seen during the day, it is usually an sign of a large infestation. Signs of infestation are droppings, gnaw marks, runs and smear marks produced by the continual rubbing of their fur against surfaces.

How To Prevent Infestations

  • Ensure that all defective drainage to your home is promptly repaired, such as broken drainpipes, and drainage chamber covers
  • Ensure your bin is emptied regularly, spillages and refuse is not allowed to accumulate in the yard or garden
  • Seal structural defects in the house to prevent rats gaining access to your home
  • Place food intended for garden birds on a bird table or feeder, do not place food scraps directly on the ground.

Removing easily accessible food and getting rid of shelter for rats are among the most basic and important preventative measures.

If signs of infestation are noticed, for example fresh rat droppings, gnawing marks, and smears, take immediate action to control the infestation.

If a baiting programme is to be successful for the control of rats it is vital to maintain an uninterrupted supply of bait.

Do not interfere with or reposition any bait stations laid as part of a treatment programme and keep children and pets away from bait stations at all times.

Page last updated on 25 November 2011