A rat in the garden is a different problem from a rat in the house

A rat in an open garden is telling you there is something worth eating and somewhere worth sleeping. Remove both and the garden stops being worth the trip. That is unglamorous and it is the whole of the outdoor job.

A rat inside the building is a different animal in the same coat. That one is a defect in the fabric or in a drain, it is yours, and it needs finding rather than baiting.

And there is a third case that most pages skip entirely, which is where the problem is not coming from your land at all. There is law for that, and it puts a duty on you and a power in the council's hands. Neither is expensive and neither gets mentioned by anyone who sells the visit.

The burrow is better evidence than the animal. The Mammal Society: rats dig their own burrows, and the entrances are usually joined by obvious well-used runs. A run is a smooth, worn track through grass or along the base of a fence, and it is what tells you this is a residence rather than a route.

Droppings separate rats from mice without any doubt. Rat droppings are described as putty-like, usually with a blunt end and a pointed end, up to 17mm long and 6mm wide. Mouse droppings are 3 to 6mm and scattered. A brown rat is 150 to 270mm of body with a tail almost as long again, and usually weighs 200 to 300 grams.

One thing worth holding on to about the animal itself: few brown rats survive more than a year in the wild, but a female can start breeding at three to four months and typically has five litters a year, of around six young rising to eleven in a larger female. So the population is not long-lived. It is fast, and it refills.

The last check is the one that changes which page you need. Look at where the garden meets the house: air bricks, the ground course, gaps where pipes go through, and drain inspection covers, which Newcastle says should be in place and in good repair. A rat that has found a way into the building is no longer a garden problem.

An open garden is the worst place to put a rodenticide down, because it is the place where the things you were not aiming at are most likely to find it, or to find something that ate it.

The UK Centre for Ecology and Hydrology tests dead barn owls sent in from across Britain, and the numbers are published. In 2021, 79 per cent of the owls tested carried detectable liver residues of one or more second generation anticoagulant rodenticides. In 2017 the figure was 90 per cent. Both were measured against a baseline of 395 owls that died between 2006 and 2012, and the 2021 report concluded that full implementation of stewardship had yet to produce a statistically significant reduction in exposure. The Mammal Society puts the same point in one line: attempts to control rat populations by poisoning may result in negative impacts on other wildlife populations.

That is not an argument that nobody should ever use one. It is an argument that a garden, with a dog in it and owls and foxes around it, is the setting where the cost of getting it wrong lands on something else.

The rules are tighter than the shop shelf suggests, too. GOV.UK: only use poison to kill the pests it is intended for, and that will be written on the packaging. Traps must be approved for the species you want to control. You must place lethal traps under cover so that other animals and birds are not caught, and prevent wildlife from eating poison you have put down. HSE adds the supply side: products sold to the general public can be restricted in the amount of active substance they contain and in where they may be used, for example only within a bait box, while professional products are restricted in who they may be sold to, and professional users of anticoagulant rodenticides work within a stewardship regime built on certification and proof of competence at the point of sale. The biocides regulation underneath all of it says biocidal products are to be used in compliance with the terms and conditions of the authorisation.

Glue traps are simply out. Setting one for a rodent has been an offence in England since 31 July 2024 under the Glue Traps (Offences) Act 2022, in Wales since 17 October 2023, and in Scotland since 1 July 2026, where using, supplying or possessing one is an offence in itself. They are still on sale. That is not the same as being legal to use.

So the order is this. Cut the food, starting under the bird feeder and ending at the compost bin. Look for burrows and runs, and look hard at where the garden meets the house. If rats are living on your land in substantial numbers, tell the council, because that is a duty rather than an option. If the source is a neighbour, a public sewer or a lateral drain, the call is to the council or the water company before it is to a contractor. And if you do end up paying someone, pay them for finding the way in and the harbourage, not for a bait box you could have bought yourself.

One stop rule throughout. If any of this takes you into a shed roof, an outbuilding, eaves or a roofline and there is a sign of bats or of birds nesting, stop there and take advice before doing anything. Bats and their roosts are protected, as are wild birds and their active nests, and getting that wrong is a criminal matter rather than a wasted afternoon.