Brown Rat

The Brown Rat is considered one of the most serious mammalian pests ever known; it's opportunist lifestyle, intelligence, agility, omnivorous diet and prolific breeding potential make it one of the worlds most successful mammals. They carry dangerous diseases such as salmonella, weils disease and rat bite fever. Rats must be controlled as they cause serious damage to property and crops. Some rats have developed resistance to modern rodenticides and that resistance is expected to increase. Rats are very difficult to trap but relatively easy to poison with rodenticides.

Your Questions Answered

Q.
I have not seen rat droppings but the bait has been taken.

Rats tend to place their dropping in specific resting/lounging/feeding areas and you will not necessarily see the droppings at the bait points. Just make sure that the bait cannot be taken by non-target species.

Q.
The bait has been taken from the trap, but the trap never went off. Should I keep traps in same area until a pest control service arrive?

The bait might be taken by mice which may not be heavy enough to set off the traps. Also it sometimes happens that a clever rat is able to take the bait without setting off the trap, especially if it is a cheap trap with a poor trip mechanism. Keep trying in the same area.

Q.
Why do rats go back to same site if no food is there?

If food was there previously they are just checking it out on their rounds. If no food was there before, then it is probably a desirable retreat for other reasons, water, safety, potential nesting etc.

Q.
My problem is Brown Rats! I live in a sheltered housing complex ran by a Housing Association,in the UK. We are not far from a river, and I can see some of the rat holes in the banks. I live in a very nice ground floor flat, that had new plastic double glazed windows fitted around two years ago, what concerns me is that they pivot from the top and swing outwards at the bottom, and there are shrubs in borders that are at window cill height below every window giving them cover. I and other residents are worried that hungry rats could come indoors via the open windows; I have known them do this at a nearby kitchen not in our complex. If the windows were the type that tilted so they could be opened at the top instead of the bottom we would feel safer, but they do not so is there a guard that could be used at the openings or would it be reasonable to ask them to reduce the height of the shrubs? I realise rats are a big problem; they are often by the doors if I go out at and seem braver in that they do not scatter when I appear. Can anyone give any advice please? Michael Cant mickcant@freenetname.co.uk

I can see you have a very real potential problem. You are right that the windows should have been fitted with a top tilt. Are you absolutely sure that they do not have a top tilt option? If not, those windows can almost certainly be fitted with a modified mechanism that allows top opening tilt. Check that out with either the manufacturers or the Housing Association, but don't be discouraged if the HA say it is not possible, they may just be looking for an easy life. Get them to give you the manufacturers details.

Trimming or better still eliminating the vegetation beneath the windows would be good and the HA should do that for you right away.

I don't think you will find any product that will exclude rats whilst allowing the windows to open easily. But I may be wrong.

Good luck with the window conversion option.

Q.
Does having a dead rat scare other rats from coming around?

Rats are naturally cautious creatures and may well be put off of taking bait if it appears to be harming other rats. However one dead rat is unlikely to deter a colony of rats if there is a plentiful source of food and the smell of a decaying rat is most unpleasant. Dead rats that have been poisoned need to be picked up in case non-target animals get hold of them

Q.
how long after a brown rat dies in a house does it give up that terrible smell ,i am trying to establish the lenght of time it could have been in my cupboard

How long a rat takes to decompose depends on the environment. The damper it is the longer it takes. In summer the smell is more intense but lasts less time, in winter it smells less but hang around for longer. The smell will continue as long as there is moisture in the carcass. this could be anything fron two weeks to a month. Then it should start to dissipate. If you can get at the carcass to remove it, that is by far the best option

Q.
I have put down 7-8 portions of (difenacoum)grain seeds in bait boxes and it has taken the bait straight away,there are still signs of activity.What is the timescale for this to start to see an improvement.I recently caught 1(one)in a squirrel trap and disposed of it.Is this a sign that this is a large colony.They are under my decking .

Difenacoum is an anti-coagulant. The rat will die after a few days due to internal haemorrhaging. The rat suffers no immediate ill effects from the poison so will happily keep coming for the bait until it gets lethargic and dies of heart failure. Most rats will die in the nest. You should keep putting the bait down until there is no more activity. How long this will take depends on the size of the colony, but difenacoum is effective and will eliminate them

Q.
I have recently heard scrabbling in my loft and what look like slime marks that appear to be going up the brick/slated house frontage to the eves of my house.I have put difenacoum in the loft and have put raptor traps down,and have caught 2(two)mice/rats.My queastion is are the slime marks a good clue that this is the mices/rats entry point ?

Almost definitely. Rats tend to follow the same route and leave obvious rat runs after a period of time. These grease marks are signs of the body of the rat brushing against the surface and they would certainly have no problem climbing the wall of a house. It is always an advantage to be able to establish where the rodents are entering the building. This access point should be blocked off. We sell wire wool and expanding foam for this very purpose. Make sure any other possible entry holes are blocked off too and covering drains is a good idea as rats do go up drainpipes. Keep baiting until there is no more activity in the loft. Good luck

Q.
i put rat poison down it was all taken done it again the following night more was taken but not all but there was slime all over it what does this mean is it a good sign or bad

THis is a good sign as it indicates what you already know, that the rats are taking the poison. Rats commonly leave a grease trail across objects in their runs so the slime just indicates the presence and route of the rat. Diligence is needed as the poison does not work immediately. Keep being persistent and you should eradicate the problem