Time to Put Out Unwelcome Mat

There may be scores, even hundreds of little beasts eyeing your house or apartment right now, looking for a nice warm place to spend the winter. Mice, wasps, ants, spiders, squirrels and ladybirds are all hoping to become squatters. They are clever and persistent: give them the tiniest opening and you'll end up with holiday guests you did not invite.

This is the busiest time of year for pest control companies to tackle calls about dealing with mice. As the weather gets cooler, rodents can enter in large numbers looking for warmth. The primary line of defence against mice and other vermin is to prevent them from getting in in the first place – you want to seal up every entry point you can find.

The first thing to do is check for spaces under doors, even in apartment buildings. In larger buildings, mice can get into upper hallways by climbing up dumbwaiter or elevator shafts or along pipes in walls. Because they can squeeze through spaces as small as a quarter inch, gaps under or around doors should be sealed with weatherstripping and with coarse steel wool around pipes. Mice can also be deterred from entering a building by cleaning out debris in basement window wells and keeping wood piles two feet from your house.

And owners of all buildings – including apartment buildings – should make sure there are no cracks or other openings in the exterior that can provide entry. And in basements, if windows are open, make sure there are screens on them.

In addition, bird, dog or cat food should not be left outside the house. There also should be no shrubbery against the house and no excessive amount of mulch, which rodents can easily burrow into.

Mice typically mount a ground assault on a house but squirrels usually attack at the roofline. Squirrels can be a particular problem because they gnaw incessantly on anything they can sink their teeth into, including electrical wiring. Tree limbs should be cut back a sufficient distance – at least six feet from the house – so they can't go airborne to the roof, where they can chew their way in through soft wood or crawl through spaces between flue pipes or chimneys.

Wasps are another pest, and are notoriously difficult to spot especially if they have made their nest in the overhang of your roof – a desirable spot for these insects. Wasps can also make nests behind aluminium siding and get into attics and roof areas through vents and around pipes and windows.

Wasps typically hibernate over the winter, but can be trouble come spring. Once they're inside the attic or the walls and it starts to warm up, the wasps start looking for light. If the first light they find is indoors, they will end up inside. One solution now is for a professional to spray areas where wasps enter to prevent them from making nests behind siding; another is to install screens on attic vents.

Other animals that try to take up winter residence include spiders, cluster flies, ladybirds and beetles. While the latter three are little more than a nuisance, spiders bite, and some people are allergic to the venom. So, any spider webs outside or inside should be removed using a vacuum cleaner.

Any infestation should be addressed. If you, the homeowner cannot handle the situation, it makes sense to call in a professional, because squirrels and other rodents can do damage. Your home is your castle after all, and you want to keep your castle protected from unwanted pests.