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Eliminating Rats

Getting Rid Of Rats

How do we know if we have rats and how do we get rid of them? Here we look at methods and techniques for getting rid of rats from your home.

How do we know we have rats?

How do you know you have rats? Well one clue is when you are lying in bed and you can hear Fred Astair (remember him - no perhaps not) tap dancing with Ginger Rogers on your ceiling. You might hear scratching particularly in the kitchen, you might see little black offerings left for you on the kitchen benches and you might even catch sight of one if you are quick. Just note that, as in all forms of pest infestation, by the time you actually see one you will probably have lots.

So you have a rat problem, what do you do?

Know Your Enemy - Understanding rats

First - know your enemy, you can read up about rats on the website at

Rats tend to like to run alongside vertical surfaces such as skirting boards, walls or beams where they rub their fur against the surface leaving telltale dark smudges. They are also quite amazing acrobats. In a recent case in a kitchen there were telltale dark smudges along the walls immediately above where the wall tiles ended halfway up the walls. The rats were able to run along the very narrow 5mm wide ledge, try doing that on Saturday night with a belly full of beer!

They particularly like ovens and crawl in from underneath, they will find all sorts of tasty snacks there and will of course stop for a pee or two (you will get a distinctive smell when you turn the oven on).

How to get rid of rats

I suggest you might take the following approach:

1. Take your time, as the old adage says - don't disturb the enemy when he is making a mistake. Observe and understand the rats' habits and favourite runways and haunts.

2. Use glue traps, they are very effective, I have caught up to five on one trap at one go. Buy lots and place them on the runways you have identified. Place them under the oven and under cupboards against walls. A good place is right in front of a hole they use to get in or out.

Remember rats are smart and will quickly learn to avoid the traps, this is why you need lots of traps - you have to get as many as you can at one go.

Use the traps for a couple of nights then leave it for a while and let them settle down again before you have another go.

3. Glue traps are very effective for the odd rat or two but for serious infestations you could ring your friendly household pest controller who will send out some nice chaps who will play their flutes and leave yummy (to rats that is) titbits around the place in small cardboard trays. These chappies know the sort of places that rats hang around and the best places to leave their offerings. The food pellets are very tasty to a rat (I'm not too fond of them myself, a bit too salty I'm afraid) but they contain a rather strong chemical that deactivates vitamin K which can be good for you if you have thick, clotting blood but is generally not a source of extreme wellness (what a horrible word) for rats which have a tendency to bleed somewhat and slip off their mortal coils into an ongoing negative survival situation.

4. You could always do the rat baiting yourself. You need to put the rat bait in places you identify as places the rats frequent. Check and top up the rat bait from time to time, this will tell you if they are eating it. If the rat bait is not vanishing in the night then either you don't have any rats anymore or else the baits are in the wrong places.

One of the good things about rat bait is that it takes time for the rats to die so they will not associate the bait with danger, they won't learn to avoid it.

If you use rat bait you should start to see results in 3 or 4 days.

Rat Bait Chemicals

There are several types of rat bait that work on the same principle.

Dicoumarol (or dicumarol)

The chemical Dicoumarol (or dicumarol) is a naturally occurring chemical of combined plant and fungal origin that acts as an anticoagulant. Dicoumarol was discovered in 1940 and was used until it was replaced by Warfarin in the late 1940s.


Warfarin is probably the best known rat bait, it works as a blood anti coagulant so the animal bleeds to death. Anti coagulants don't work immediately but are used in doses that build up in the body of the rat and eventually kill it. As we all know Warfarin is used to treat humans with blood clotting conditions such as stroke.

Brodifacoum (locally known as brodifakum)

Warfarin has in turn been replaced by brodifacoum (locally known as brodifakum), a second generation super version of Warfarin which is more lethal and longer lasting (20 to 130 days) than its predecessor. It has become one of the world's most commonly used pesticides and is available under many brand names such as Ratsak and Ratgone (check the packet for the active ingredient).

But I still have rats

Something to note is that if you are in a country area, particularly near rice fields you may find that after you have got rid of the rats in your house the rat poison keeps being eaten. This is because rats will come from the nearby area to eat the yummy stuff. You are providing a banquet for the whole district.

Care with poisons

It should also be noted that brodifacoum also kills other animals such as mice, rabbits, guineau pigs, squirrels, cats, dogs, birds and fish so you need to think carefully how you use it. Remember that a single dose is unlikely to kill the animal, the treatment depends on several meals and a build up of the chemical in the body. Owing to low concentrations in the bait it is considered of low hazard to humans. It can be absorbed by the skin so you should wear protective gloves when handling it.

The antidote for these anticoagulant chemicals is vitamin K1 and in the rare cases of poisonings such as attempted suicide (not a sensible way of kicking your bucket) the long lasting effect of the chemical requires long term treatment with doses of vitamin K1.

Catching rats without poison

If you don't like the thought of using a poison, particularly a slow acting one, then you probably need to use a constraint method which causes no pain to the rat and is selective such as a rat trap in the form of a cage with a hinged door or a glue trap. You can then dispose of the rat humanely (note that, in spite of what the National Association of Rat Compressors might tell you, compression methods are not exactly humane).

If none of the above solutions suit you you can always seek out that ever so illusive Pied Piper, you will probably need earplugs and, whatever you do, keep him well away from the children. Alternatively you could always go and live in the antarctic, not many rats down there.

Copyright © Phil Wilson 2015
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