Mice
Can you hear the pitter-patter of tiny footsteps behind the skirting? Does Tom keep bringing Jerry in from the garden?
Mice are a part of British wildlife - but when they take up residence with you, they can be a cause for concern.
Active all year round, mice are one of the most common pest species in the UK.
Mice are small mammals of the order Rodentia. Although commonly identified as pests, some are bred and kept as pets.
Globally there are hundreds of types of mouse, including varieties such as the deer mouse (Peromyscus), house mouse (Mus musculus domesticus), wood/field mouse (Apodemus sylvaticus), Edible dormouse (Glis glis), spiny mouse (Acomys) and even the striped zebra mouse (Lemniscomys).
The dangers: why we control mice
Although mice are often considered to be cute by some people, they are a public health pest and can cause serious harm.
Mice have been known to spread nasty diseases - such as Salmonella and Listeria - to humans through their urine, droppings and bedding.
Mice have a need to mark their territory with their urine and due to their sporadic eating habits, build nests near food sources. This puts anyone with an infestation at risk of food poisoning.
As they scurry around, they carry dirt and bacteria with them, transferring it to your counter tops, cabinets, pantry and anywhere else they travel.
These nibbling nuisances can also cause a lot of property damage, due to their compulsive need to gnaw to maintain their teeth at a constant length.
Electric cables, water and gas pipes, packaging and woodwork may all be seriously damaged by mice - many instances of electrical fires and floods have been attributed to them.
Mice around businesses
Property and land owners have a legal obligation under the Prevention of Damage by Pests Act 1949 to keep premises rodent free, or, if rodents pose a threat to health or property, to report infestations to the local authority.
Owners of food businesses also have obligations to keep premises pest free under the Food Safety Act 1990.
Environmental Health Officers or General Enforcement Officers can issue enforcement notices to business owners who don’t have adequate pest management procedures in place.
If not complied with, these can lead to fines or even a stint in jail and a criminal record.
And if a company or organisation has a highly publicised mouse problem, then it will heavily impact its reputation.
If clients and customers spot evidence of rodent infestation in the premises you manage, they are unlikely to want to do business with you.
And several widely shared social media posts can help spread a negative image.
Types of mice in the UK
In regards to pest management, there are two common types of mouse in the UK to be aware of:
House mouse (Mus musculus domesticus)
Field mouse or wood mouse (Apodemus sylvaticus).
If you come into contact with a mouse, chances are it’s a house mouse.
These mice are known as “commensal rodents”, which refers to them living with or in close proximity to humans.
Commensalism is defined as a long-term interaction in which members of one species (ie mice) gain benefits, while those of the other species (ie humans) neither benefit or are harmed.
Field mice are much more suited to nesting outdoors, but will possibly move indoors once the weather gets colder.
Habitat: how mice choose a home
House mice are found in and around human structures as they rely on warmth and shelter for nesting sites, and our readily available food sources.
Nests are often built in places such as roof spaces, under floors or in wall cavities, sheds, basements, storage boxes and wherever there is access to a good source of food and safe, warm harbourage to breed.
Outdoors, field mice will excavate burrows in which to build nests of dry grass, but they will also den among rocks and crevices.
Their main priority will be building a nesting site that isn’t accessible to predators, including cats, foxes, birds and even other rodents, like rats.
Where do mice come from?
Mice are naturally inquisitive and can squeeze through cracks as small as 5mm, to search for food and shelter.
If a neighbouring property has an infestation, this can spread very quickly into your home or business.
They can also come into your property by climbing vines or trellis against the walls of your building.
If you have a lot of vegetation and foliage nearby this is perfect for mice to shelter in, until the time comes for them to find somewhere warmer.
The tell-tale signs mice are about
Their presence is usually detected from one of the following signs:
Mice droppings - these are often black, and about the size and shape of a grain of rice. Fresh droppings will be soft and moist. Each mouse can leave approximately 80 droppings per day. Common places to find mouse droppings are under the kitchen sink, around central heating boilers and in roof spaces
Strong ammonia smell - mice urinate frequently
Smear marks - these are dark grey marks left on surfaces by repeated contact with the oils in mouse fur
Nests - sometimes nests can be found indoors for example in lofts, under floorboards or in airing cupboards
Damage to stored food in cupboards and pantries
Gnaw marks on materials such as wood, carpets, paper, pipe cables and furniture.
Why are mice more common in winter?
Mice do not hibernate and are a problem all year round.
House mice are already living in and around wherever we are.
But as the weather gets colder, those field mice currently surviving outdoors will look for warmer places to nest and begin to move indoors.
They are highly adaptable and won’t hesitate to take advantage of a cosy human structure during the winter months.
Food is also an issue - they begin to scavenge closer to humans, as their own sources are no longer plentiful.