Harrier Pest Control

Rats and Mice

Harrier Pest Control deal with rat and mouse infestations throughout the North West.  In the cases of both rats and mice we do an inspection of the property to assess potential harbourages, entry points and food supply. Where rodenticide needs to be placed in the presence of children or pets it will be placed in tamper-proof boxes into which the rodents can enter to feed but children and pets cannot open. Rodenticide placed outdoors will always be in safe external bait stations. Harrier Pest Control support The Campaign For Responsible Rodenticide Use whose logo you will find on this page.

Harrier Pest Control will normally require at least four visits and possibly more to clear a rat or mouse infestation.

Mice (Mus musculus domesticus)

House Mouse

House Mouse

The house mouse  is one of the most numerous species of the genus Mus. Although a wild animal, the house mouse mainly lives associated with humans, causing damage to crops and stored food.

Mice are mostly crepuscular or nocturnal; they are averse to bright lights. The average sleep time of a captive house mouse is reported to be 12.5 hours per day. They live in a wide variety of hidden places near food sources, and construct nests from various soft materials. Mice are territorial, and one dominant male usually lives together with several females and young. Dominant males respect each other’s territory and normally enter another’s territory only if it is vacant. If two or more males are housed together in a cage, they will often become aggressive unless they have been raised together from birth.

House mice primarily feed on plant matter, but are omnivorous. They will eat their own faeces to acquire nutrients produced by bacteria in their intestines. House mice, like most other rodents, do not vomit.

If mice have an ample source of food they will not forage far from their resting place and providing the moisture content of the food is greater than around 8% they do not need to drink water.

A mouse is able to pass through the tiniest of gaps and as a rough guide if a gap is large enough to pass a standard ballpoint pern through then a mouse will pass through it.

The first sign of a mouse infestation is often the presence of their droppings which are liberally distributed as they move about. They have little in the way of a bladder and constantly dribble urine as they move around with consequent contamination of surfaces as they cross over.

Care must be taken when droppings are found in lofts etc so as not to confuse them with bat droppings which are visually very similar.

Rats (Rattus norvegicus)

Brown Rat

Brown Rat

The rat population of Britain is currently at an all time high, fortnightly bin collections, lack of sewer baiting and the late-night takeaway are all cited as culprits in this rodent explosion.

Rats are rodents, the word comes from the Latin ‘Rodere’ meaning ‘to gnaw or eat away’, aptly named as their teeth never stop growing and they gnaw on hard objects to keep them sharp, unfortunately this can often include electrical wiring and water pipes. A rat’s teeth can penetrate mild steel.

Often a rat will move into a loft or roof void looking for somewhere safe to give birth, being excellent climbers the interior of the cavity wall of the building is a common route, especially if there is an underground breach in the drainage system.

They are sexually mature at around 13 weeks and have a gestation period of about 20 -22 days giving birth typically to 7 – 10 young per litter.

They are naturally shy and nocturnal creatures said to suffer from ‘neophobia’ a fear of anything new in their environment.

Often the first signs that a house is infested will be the patter of tiny feet on the upstairs plasterboard ceilings, although with the modern trend for roof insulation an infestation can often go undetected for quite some time. In homes with floorboards gnawing will often be heard in the sub-floor area.

Their need to eat will often betray their presence, food stored in cupboards will be taken, cereal packets chewed, chocolate and crisps are favourites, although a rat often has a diet that we would find somewhat strange.

The rat has no ability to taste ‘bitter’ foods so it can quite happily munch away on a bar of soap for the fat content. Pest controllers use this as a safety feature and all rat poison is coated in a bitter substance that the rats can’t taste but which would make it totally unpalatable to a dog or a child.

Although the rat is no longer a plague carrier it does come with a number of unwelcome traits. It is a carrier of a number of diseases including Murine Typhus, Salmonella and Weil’s Disease, spread from rats’ urine, which unfortunately usually claims at least one life in Britain each year.

If you have a rat infestation then you have a legal duty to remedy it and in extreme circumstances forced entry to your property can be made against your will.

As a final sting in the tail, many household insurance policies specifically exclude damage by vermin so if a rat chews your wiring and the house burns down you may find yourself without insurance cover.

Increasingly we see them but what do we really know about the humble creatures that thrive in our sewers and induce almost universal fear and loathing in all who encounter them.

A typical rat weighs around 200 – 300 grams or half to three quarters of a pound, and has a tail around the same length as its body, often making it appear bigger than it really is. One of the primary functions of a rat’s tail is thermo-regulation; it uses its tail to dissipate body heat. When a rat’s temperature falls it restricts blood flow into its tail.

Rats are not native to Europe or North America but originate in Asia and almost certainly arrived in Europe as stowaways on trading ships, indeed the common name for Rattus rattus is the ship or black rat.

In Asian folklore the rat is a prominent and often popular character. In Hindu mythology the elephant-headed god Ganesh is accompanied by a rat wherever he travels, an offering to Ganesh and his companion Vahana the rat is therefore an important part of Hindu worship.

To the Romans the sighting of a white rat was considered to be lucky but if you found that rats had chewed your belongings then you should postpone any business affairs that you were planning that day or they would surely fail.

Reviled in the west, the rat is revered in Chinese mythology, being part of the Chinese zodiac and respected for its quick wit and resourcefulness. The rat is considered good luck in China & Japan where it is credited with bringing the gift of rice to the world.

To the wandering Polynesians rats were an easily bred and transportable source of food.

In Britain and Europe rats have probably altered the course of history more than any other creature except man himself.

In the wake of the already earth shattering English win at the Battle of Crecy in 1346 Europe was about to undergo a monumental change in a most horrific and brutal manner that would see up to half the population wiped out and the very fabric of society altered forever.

It is said that in 1347 the Mongols laying siege to the Crimean city of Caffa began to succumb to a mysterious illness that killed swiftly and mercilessly. In order to weaken the city the Mongols catapulted the bodies of their own dead over the city walls and within days the inhabitants of Caffa also fell prey to the disease.

Food Contamination

Food Contamination

However, a group of Italian merchants escaped or were allowed to leave the city and return to Europe. Unknowingly they probably carried with them the Black Death, Yersinia pestis.

The ensuing plague raged throughout the continent reaching Britain in 1348 with up to ninety percent mortality in some areas and it reappeared in Europe in every generation for over four hundred years.

We now know of course that the rat was a carrier, or to be more precise the fleas that the rats carry on their bodies were the agents of plague transmission.

Indeed whilst being in no way established in fact, it is possible that the children’s story of the Pied Piper of Hamlyn is an allegory of the plague, it certainly indicates that the rat population was booming at the time.

Every cloud however has a silver lining and the survivors of the 14th century plagues found that they could now demand higher wages and better conditions as the shortage of workers in the wake of plague deaths created a sellers market for labour. The rise of the Yeoman Farmer and the British class system could be argued to be attributed to the humble rat.

Into modern times and the Black Rat is now almost extinct in the British Isles, having been replaced from the 18th century onwards by the Brown or Norway Rat (Rattus norvegicus) and it is this creature that now thrives in our sewers, on our streets and in our homes and it is when we encounter it there that it creates most revulsion.

Hated, despised and unloved the humble rat continues to share and shape our environment in ways that we do not see or appreciate and despite our best effort the rat and man will always co-exist.

Recommended Reading