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BROWN RAT

Brown RatIdentification & Biology of Brown Rat:

 

  • Brown to light grey in colour with lighter underside
  • Weight about 400-500g
  • Small ears & eyes
  • Tail is slightly shorter than body, it is dark above & lighter below

 

The brown rat (Norwegian rat) has an excellent sense of taste, smell & hearing, although poor vision. They are strong swimmers but wary of new objects (Neophobia). In the right conditions rats can live up to 3 years. A female can produce 4-6 litters per year with 8-10 young in each litter. In other words one female rat can potentially produce up to 180 young in a lifetime.

Where brown rats live & how they affect you:

The brown rat can gain entry to buildings by gnawing, climbing, jumping or swimming through sewers & even entering through toilets or broken drains. They will live anywhere that there is food, water & shelter. They can live in lofts, cellars, under garden sheds; compost heaps, as well as burrowing underground. They carry diseases such as Salmonella, Weil’s disease & Toxoplasmosis, which makes them a very serious pest indeed. Signs that you may have a rat infestation include:

  • Holes
  • Droppings 3-5mm in size, rod shaped
  • Distinct ammonia- like smell caused by the breakdown of rat urine
  • Runs
  • Smear marks on walls left by dirty fur after contact
  • Gnaw marks
  • Damaged goods
  • Nests

Fresh soft droppings will be found along well travelled pathways in areas of food & near their harbourage. Tracks with footprints & tail marks can be found on dusty areas, along with urine trails. You may experience noise in walls created by gnawing & climbing, largely at night time when brown rats are at their most active. Rats are very explorative rodents whom memorize the locations of pathways, obstacles, food, water & shelter. They will detect & avoid new objects & novel food (Neophobia) & will therefore frequently avoid traps & baits for many days following their placing. The brown rat will typically grab food & carry it to a different place to eat. They prefer to eat grains, meat, fish, nuts & some fruits. They can squeeze beneath a door with as little as a half inch gap & will gnaw through wooden doors. The brown rat will seldom travel beyond 300 feet of their nest. Structural damage such as the fabric of buildings or electrical wiring can be damaged by the brown rat with the latter acting as a potentially serious fire hazard.

The brown rat is a significant health & safety issue. A rat- free premises is a legal hygiene requirement: Health & Safety at Work Act (1974) & Food Safety Act (1990) for businesses. In hospitality & food related business rat pose a serious risk to your good reputation, in addition to the real possibility of prosecutions or even closure.

Control measures for brown rats:

An effectual rat extermination plan begins with the location of droppings & identifying harbourage positions & entry points for proofing. All food sources need to be removed or unobtainable. Sewers can often be entry points for the brown rat & this will require an internal inspection to detect any defects & problems. Health & safety & the environment dictate the type of bait & the active ingredient used in different locations. Rats are by nature shy of new objects & it may well take a week or so before they take new baits. Other rat control methods include break back trapping & glue boards. It is also recommended that the most common entry points, pipes, wires, cables & underneath doorways are thoroughly proofed using aluminium plates, gauge wire or cement as appropriate.

Brown Rats - Helpful Tips:

Hygiene is of key importance to the control of the brown rat and the following is necessary to eliminate the problem:

  • Protect potential food sources from attack by storing items securely
  • Keep food cupboards & work surfaces clean from crumbs & other food particles
  • Block any harbourages, which create the ideal hiding place for breeding sites.
  • Create accommodation that is easily cleaned, to avoid the accumulation of debris.
  • Securely store any rubbish.
  • Tend to any over grown gardens, especially piles of wood, bricks etc.
  • External dog pens must be maintained properly.