How to Tell If You Have Rats in Your Cambridge Property

Most people suspect rats long before they see one. A noise in the ceiling, a hole under the shed, something chewed in the garage. This post is about turning that suspicion into an answer: what to look for, where, and how to tell current activity from old.

Where to Look First

Rats keep to cover and edges. They move along walls, behind appliances, under decking and along fence lines rather than across open space. Start your search in those places, with a torch, and look low.

• Behind and under the cooker, fridge and washing machine
• Under the sink and around the boiler, where pipes pass through walls
• The loft, especially near the eaves and on the insulation
• Garages, sheds and summerhouses, particularly along the back wall
• Under decking and at the base of fences, compost bins and log piles
• Around inspection chamber covers and gullies

The Signs, and What Each One Tells You

Droppings

Rat droppings are dark, roughly the size of a large grain of rice or bigger, and blunt at the ends. They tend to be grouped in one place or along a route rather than scattered widely. Mouse droppings are much smaller and spread about. Fresh droppings are dark and slightly shiny; old ones are dull, grey and crumble when pressed with a stick. Wear gloves and do not handle them directly.

Runs and smear marks

Rats reuse the same paths every night. Indoors that leaves dark, greasy lines at the bottom of walls, around the edges of holes and along pipes. Outdoors it leaves flattened tracks through grass or along the base of a fence.

Gnawing

Look for fresh tooth marks on skirting, door edges, plastic pipes, food packaging, bin lids and cable sheathing. Fresh gnawing looks pale and clean; old gnawing darkens.

Burrows

Holes roughly the width of a fist or smaller, often beside a wall, under a shed or slab, or in a bank. A burrow in use has a smooth, worn entrance with loose soil nearby and no cobwebs or leaves across it.

Noise

Scratching, gnawing and a heavier scurrying than mice would make, mostly after dark and often in a ceiling, under floorboards or inside a wall. Noise in daylight, especially early morning, is more likely a squirrel or a bird.

Smell and pets

An established infestation has a stale, musky smell, strongest in enclosed spaces like lofts and under stairs. Dogs and cats often notice before people do, and may stare at, sniff or scratch at one spot on a wall or cupboard.

Is It Happening Now?

Old evidence can sit in a loft or under a floor for years. Before calling anyone, it helps to know whether you are looking at current activity.

• Flour test. Dust a thin layer of flour or talc across a suspected run and check it the next morning for footprints and tail marks.
• Clear and recheck. Clean up droppings in one spot, wearing gloves, and see whether fresh ones appear over the next few days.
• Burrow test. Loosely plug a burrow entrance with soil or scrunched newspaper and see whether it is reopened.

Rat, Mouse or Squirrel?

Getting the species right matters because the treatment is different. Our guides on rat droppings versus mouse droppings and signs of mice help with the first question, and the squirrel or rat in the loft guide with the second.

What to Do Next

If you are still unsure, a pest inspection and survey is £120 fixed cost and tells you what is there, how much of it, and how it is getting in. If the signs are clear, our rat control service is £260 with no call-out fee, confirmed before anything is booked; the rat control cost guide explains what that covers. Once you know it is rats, our post on how to get rid of rats sets out the order to deal with them in.

One sign is a suspicion. Three in the same place is an answer.