Foreign pests in the United Kingdom

 It's hard to imagine the United Kingdom without our most notorious pest, the rat. However, most of our common rodent species are not native to the United Kingdom and have come to our nation through ships from overseas, several centuries ago.


The black rat

This species is not native to the UK and it wasn't until the 13th Century that the Black Rat was bought over in trade ships from tropical Asia. Initially, rats could only be found in ports where ships from Asia docked, however the population spread quickly across the country. The black rats bought with them fleas which carried the Plague virus, a disease that killed almost a third of the people in Western Europe during the 13th Century.

          A black rat

The Plague of London famously killed over 70,000 people in city alone during the 1664-1666. This death toll of the Plague of London is a frightening testimony of the danger that rats carry and the speed at which rat populations can spread and reproduce. Yet, to see a black rat today in the United Kingdom, it is almost unheard of, with only a few isolated sightings near dockyards. The black rat has been effectively outbred by its more aggressive cousin, the brown rat.

In the modern age rats don’t tend to have the same devastating effect on society, though they still pose a real threat to our health as they are known to host parasites that carry disease. Even today, there are isolated cases of plague caused by rat infestation as well as numerous reports of Weil’s disease and salmonella caused by rodent infestation.


The brown rat

          A Brown Rat

The Brown Rat, commonly known as the Norway Rat arrived in the UK in the latter half of the 18th century. Although the name indicates that it originated from Norway, this was in fact a misconception during their ascent to the UK in the 18th Century. The brown rat originates from Northern China and has spread to all continents, excluding Antarctica, making it the second most successful species (Humans being first). The brown rat is a burrowing species and although it originally resides in woodland it now can be found wherever humans reside.

The brown rat is the most common rat in the UK and is the culprit for the vast majority of household rat infestations. He is the most common rat in the UK and is the culprit for the vast majority of household rat infestations. He is much less selective with his choice of food and will eat almost anything. In addition, generations of urban rats have now developed a taste for fattier human foods over their natural diets of seeds, insects and smaller animals, which make human inhabitants even more attractive to rats.


The house mouse

The field mouse is thought to be native to our shores. However the larger house mouse originates from South Asia, around India and arrived in Western Europe in a similar fashion to rats, on trade ships. The house mouse generally resides amongst humans as we can supply an easily accessible source of food and shelter. They occupy houses, barns and granaries but will also live in woodland area. By nature mice are herbivores, consuming fruits and grain from plants. However they have adapted to living in urban environments and will consume most human scraps including protein rich meats.


       A house mouse



The grey squirrel

        A grey squirrel

Grey squirrels were introduced to the UK from the USA in the 19th or 20th century and now reside throughout the south of England, Wales and Cumbria. Grey squirrels are widely regarded as pests due to their rapid population growth which has led to a reduction in the numbers of native red squirrels, a species under protection in the UK. The grey squirrel has been the most successful species of squirrel in the UK, largely because of their larger size and ability to store fat throughout the winter.

Grey squirrels are considered a nuisance because of their tendency to steal from garden bird feeders and sometimes eat bird eggs and fledglings. Squirrels are known to become household pests and can sometimes infest lofts causing structural damage, tearing up insulation bedding, chewing timbers and posing a fire hazard by stripping insulation from electrical cable.



Rodent control

When dealing with rats we advise that you use chocolate or mayonnaise as bait, although you might have to try different types of food to find the right temptation specific to your rat infestation. Electronic rat traps such as the Victor Multi Kill provide an effective means of pest control. However the original snap trap remains the most popular form of rat control worldwide. We carry a range of mouse control products and humane squirrel traps.


Written by Marion C. European Ecommerce Content Specialist at Victor Pest.

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