The Brown or Norway Rat can measure up to 40cm in length (including the tail). Fur colour can vary but is generally dull brown/grey in colour. Rats are omnivorous and whilst they generally feed on cereals and grains, if hungry they can take small chicks and eggs.
One of the main characteristics of rats is that they are neophobic – very wary of anything new and they can take 4-5 days before they accept a new object into their environment. They prefer small-enclosed spaces and get around by smell & touch. They like to be up against something as they travel like a wall or pipe.
Contrary to popular beliefs regarding rats being dirty they are in fact very clean animals and spend up to 20% of their time grooming. They are however carriers of a number of diseases, the most publicised of which is Weil’s Disease which can be fatal to humans. Rats take between 2-3 months to reach sexual maturity and can have up to 7 litters per year with the average litter size being about 8. The other UK rat is the Ship Rat or Black Rat which is now very rare and restricted to a few localised port sites.
In contrast to mice, rats tend to have only a few feeding sites and so the key to successful control is to ensure there is a good quantity of bait available (sub-lethal doses can affect the level of control which will be achieved longer-term). Whole grain and block bait is the most commonly used, and active ingredients such as Difenacoum and Bromadialone can be used indoors and out.
Rat burrows can be baited directly if safe to do so and trapping and use of gassing compounds such as Aluminium Phosphide (professionally trained operators only) can be considered.