My house is like a scene from a Tom and Jerry cartoon - minus the cat. I open the oven door and see a mouse perched in a bowl of scones. Sarah Marriott didn't anticipate becoming a rodent expert when she moved to the country. But they've given her no choice.

I lift the lid of the dog-food bin and, instead of scooping out dog cereal, have a beady-eyed field mouse in my hand. I wake in the middle of the night to the sounds of scuffling and chewing in the roof. Most mornings I sweep up crumbs of polystyrene, from chewed roof insulation. And I keep a sweeping brush in the bedroom - repeated banging on the ceiling scares them away for a while, so I can get a few hours' sleep.

The annual battle against wildlife started late this year but has escalated quickly. From previous invasions I know that plug-in sonar repellents don't do the trick, so in October I bought my usual array of traps for mice and rats. Nothing newfangled for me: the old-fashioned wooden board with a metal spring guaranteed to bruise any finger and kill any rodent unlucky enough to get in its way usually works when baited with something tasty (pitta bread seems popular with mice around here).

A friend, appalled at the traps' brutality, urged me to get the animal-friendly type, which merely captures the creatures. "But they'll only come back, so what's the point?" I asked.

Apparently, to avoid Mouse Invasion: The Sequel you have to take the captives far, far away into the countryside before setting them free. I was willing to give these friendly traps a try - despite fearing that my furry visitors were homing mice that would tramp over hill and dale to get back to my cosy scone-filled kitchen - but the local hardware store, in Ballaghaderreen, Co Roscommon, doesn't stock them.

I should point out that I have nothing against mice. They don't frighten me and I have no desire to harm them or any other living thing (except midges, cockroaches and mosquitos), but I don't want them wandering around my kitchen.

The hygiene routine is just too exhausting. I can't allow a single crumb anywhere in the house or a mouse will appear. One morning, after finishing a slice of toast, I looked down at the plate to see a little grey mouse staring up at me. And making anything to eat is an ordeal, because every surface, from a chopping board to the grill pan, has to be sterilised before so much as slicing an onion.

At the start of the month I had to buy more mousetraps, as the original five had become bloodstained with use and weren't sufficient to deal with the nightly onslaught. Some evenings I catch one an hour; the click of the traps sounds like a metronome, a regular punctuation to an evening's relaxation. My kitchen floor is so festooned with the things that it's off limits to children and pets in case they get hurt - there's even one in the oven.

Until I can get hold of some animal-friendly traps, I don't see an alternative to using the old-fashioned guillotine type. The popular option of rat poison is no good, as it can affect other animals - many pets are poisoned and die painful deaths from licking the poison itself or from eating rodents that have been poisoned.

But it's good to know that I'm not alone, that it isn't my questionable hygiene that is attracting Jerry and his friends. Mrs Mulligan in the hardware store is doing a roaring trade in mousetraps.

"But what about cats?" I asked her. "Modern cats are no good," she said. "Too well fed." Would dogs do the trick, I wondered.

That evening, as the scuffling started, I heaved my 24-kilo Airedale terrier - a type of dog originally bred in Yorkshire for hunting otters and also used as police dogs in Japan and Russia - up the stepladder to the mezzanine platform above the main bedroom.

Bessie spent most of the night sniffing and scratching at the bottom of the A-shaped panelled pine ceiling where it meets the top of the three-foot-thick stone walls. Although she didn't catch a mouse, her scent may have scared them off, as all was quiet for a week or so.

My next battle manoeuvres involve yet another attempt to find - and block - the holes where they're getting in and, if that doesn't work, a trip to Dublin for animal-friendly traps.

Being able to distinguish a mouse from a rat isn't a skill I thought I'd acquire on moving from the city to embrace rural life, but it's important to use the correct type. A mousetrap isn't big enough to catch rats, which may simply drag it around attached to a leg, and tiny mice aren't heavy enough to set off a rat trap, so they get to snack scot free on my pitta bread.

Dealing with my mouse incursion has taught me two other lessons: country living isn't for the squeamish, and Tom and Jerry cartoons aren't as funny as I used to think.