Four rodent control strategies to combat infestations

In London, there are many types of rodents that are beneficial to the ecosystem. And other rodents are considered a pest because they are invading species not native to this country, affect our activities, or invade our homes. As such, rats and mice are quite common in London. However, rodent control should not be seen as senseless killing but rather a way to save what is important. We need to know how to prevent rodent infestations from taking place.

Recognising the signs of rodent infestation

Normally, when I think about rodent control, I would speak about residential pest control. But speaking about this subject, a striking memory comes back of an island being devastated by a rat infestation destroying the defenseless nests of sea birds. A sad rock lost into the sea, with no natural predator where the birds have been breeding for thousands of years. We think of an invading species as coming from an exotic land. It is the case for the grey squirrel, for sure. But an invasion is an imbalance that is forced on native species with dramatic consequences.

In an urban concept, having too many of a certain type of rodent may become too much of a burden on certain individuals having to fight it alone or services having to face a higher level of damage repair and maintenance. Some signs of rodent infestations include rodent droppings, burrows, and hairs, of course. Garden rodents will damage our plants and mess up our landscaping endeavour. Rodents in home environments will transmit rodent diseases. Rodent in lofts will cause damages to the insulation material and roof beams as well as prevent people from sleeping.

A rodent infestation may cause pressure on the surroundings

In simple words, if a certain rodent population increases exponentially, it will occupy more land and consume more resources, leaving other species to suffer the consequences. And we saw earlier how rats, in particular, can be a threat as a predator to other species. As a result, you may notice that birds do not visit certain areas so much or that certain plants are not flourishing as usual. If allowed to go on over a large period of time, you may be able to recognise a run path that is bare of vegetation. Rodent control would hence be an attempt to regain some sense of balance and give a fighting chance for others to recover.

Damages caused by rodents

Rodent bite marks on the wood of a skirting board, beam, or door are the most typical sign of rodent infestation. It is part of their nature to gnaw at materials to keep their incisive teeth filed down. But as they do so, it creates more and larger rodent holes that will allow them to travel more easily.

A more worrying type of rodent damage is to cables and PVC pipes. The obvious consequence will be the resulting fault that will need repairing by an appliance engineer, an electrician, or a plumber. The possible consequence may be a fire, in the worst case, or flooding. What is particularly vulnerable is the flexible hose for toilets. They are made of soft plastic and can be broken through in no time, allowing a rodent to come into your living space and causing a mess.

A client asked us once how to stop rodent damage to cars. They were parking their fleet of vehicles in outdoor parking. The rodents were going there for heat and were cutting through the car wiring and hoses. Short of parking your vehicle in an enclosed area, any form of rodent control will only manage to mitigate such damage.

But in some instances, finding the signs is simply too little and too late. Taking notice of storage unit rodent damage simply comes too late to do us much good. What you would rather want is the storage unit manager contracting a rodent pest control company.

What are the best rodent pest control methods?

There are basically four effective rodent control strategies:

• exterior rodent control
• pest control rodent proofing
• rodent repellent
• rodent removal

1. How can we manage outdoor rodent control?

In principle, we do not want problems to come to us. So, ideally, we would want to organise things in such a way that we do not cause problems to start with or that we do not have to suffer detrimental consequences from our actions. To some extent, any animal outdoors can be considered wildlife. A distinction is made for species that are Public Health hazards.

So, the first obligation would be for local governments to have a policy in place to promote rodent control and have the necessary means to carry it out. Before rodents reach our properties, they first need to come from somewhere. Thames Water and other companies in charge of maintaining our sewer system have a very large responsibility in preventing rodent infestation. But there is simply too much to do and not the means to do it. Most local authorities used to have a free rat service for their residents, but it was mostly answering the sporadic call-outs rather than implementing a property strategy. Furthermore, most councils have been withdrawing their free rodent service, leaving affected homeowners and residents to either bear the associated rodent pest control cost or carry out DIY rodent control.

Being responsible for our properties, we can only do so much. Rodents are resourceful and can easily climb over the fences or go up and down drain pipes. In principle, homeowners should take care of their properties:

• keeping a well-manicured garden
• using a tree surgeon on a regular basis
• sealed off out-buildings and decking
• maintaining the masonry of the building
• keeping his drains clear and in good shape

The next step would be to place some outdoor rodent traps, rodent bait stations, or outdoor ultrasonic rodent repellers. But in all instances, they will all first need to come to your home before they can get chased away. So, the best would be to have all the property around you on board and doing the same as you do, so the rodent would get stopped before they can even reach you.

2. The three-step rodent-proofing for your house

Building a rodent-proof house would have been ideal. Sadly, instead of being built with rodent control in mind, what we have are houses that are designed for rodents to take full advantage of. Most of our homes have spaces within the roof, walls, and under the floorboards. Others are made out of partitions and drywall. So, the first principle is not to let them in.

• Think of your house as a boat. You would not want to water to get in for obvious reasons.
• Then think of your home as a bubble; you feel safe and protected from outside threats.
• Finally, combine the two ideas as a sandwich: the outdoor perimeter, the void spaces, and finally, the living spaces.

The above concept is easy enough to apply for a detached house, but in the case of a terrace of houses, the terrace becomes the boat, and therefore your bubble becomes your best and last line of defense. As the void space communicates openly between the terrace houses, a rodent infestation can easily spread like wildfire from one home to the next. You, therefore, depend very much on what your neighbours are or aren’t doing. If you live on the upper floor, look below.  If you live mid-terrace, look sideways.

From there, the rodent proofing work is straightforward enough. It is a matter of finding all the openings and possible access routes and blocking them all, one after the other. If despite the initial rodent proofing, you still have activity, it is because there is something you missed. The gaps around the pipework as it crosses into the living space need a rodent seal fitted around. Any other gaps need fillings up or patching up. What material you use and how you do it will depend on the task at hand and the rodent you want to keep out. But expanding foam is not suitable for rodent control.

The limitation of proofing is the noise and the smell. Even though your living space is 100% tight, the noise can travel through, or if a rodent dies somewhere within the void space, the smell can be horrendous, and on some occasions, it can be accompanied by the resulting bluebottle flies outbreak. If rodents access your home through the gutter line or from underground following the sewers, the smell and noise will never stop unless their primary route of access is cut off.

3. How to repel rodents from your home?

Plug-in rodent repellents are the most commonly used electronic rodent repellent devices in the UK. They produce a signal that irritates the nervous system of rodents. Ultrasonic rodent deterrents can also be battery-operated to be used in confined spaces or roof spaces. Also, a specially designed under-hood ultrasonic rodent repeller can now be fitted to protect the wiring and hoses of your cars.

But even the best rodent repellent will only make your home less hospitable to them. We have a lot of clients who have fitted a number of sonic rodent repeller all around their home to no avail. Furthermore, if the neighbours also have them plugged in, to some extent, they may reinforce each other in making the overall area less suitable, or they may cancel each other, meaning that the flat of your neighbour is not more friendly than yours. So once again, it is a matter of how much pressure is coming from the surrounding population and if they have a better alternative.

Simply put, we did a job in the house of an old lady who was hoarding stuff all around in her flat. She might have had between ten and twenty cats and sonic devices all around. And you might have guessed it; she had the worst level of mice infestation. The solution was to control the cat food to start with (that she actually refused to do) and remove the clutter that allowed mice to hide and be safe. My view is, if I wanted to use four ultrasonic rodent deterrents, I might place them all in the kitchen; that is, for me, the most critical area of my home.

The alternative natural rodent deterrents are possibly less aggressive than the sonic ones. We all have driven by a water depuration station and survived it. We have all changed our share of nappies or cleaned the oven with corrosive chemicals. If there is gold on the table, I will be willing to go through a few minutes of discomfort to get it if I am about to starve.

4. Carrying rodent control using rodent traps and/or rodent poison.

Rodent poison is possibly the most accessible rodent control method. But more important than the poison is what it is mixed up with. Rodent bait formulations normally include rodent poison pellets or rodent bait blocks. In some instances, contact gel or foam can also be used with good results.  But the only issue with poison is the death it causes. If a large rodent would die underneath your floors, it will generate a lot of smell. And the larger the animal, the stronger the smell, and the longer it will last.

Also, there is the issue of safety. When placing rodent poison, it is essential to place it out of reach of any pets and children. The best is to use a rodent bait station and to place it at the void space level rather than inside the living space. After all, you would not want to encourage rodents further where they are not welcome in the first place.

For large rodents such as rats and squirrel infestations, using rodent traps offers more control as to where they will eventually die and offers the possibility to retrieve and dispose of the dead body. How to set a rodent trap will depend on the model you use. There are very convenient systems that set the rodent trap as a jaw so your fingers are safely away from the teeth. Other more traditional spring traps require more caution. And other traps, such as Fenn traps for squirrels, are simply very perilous unless it is built into a protective cylinder. To get rid of rodents in an attic, you should always start with trapping before placing rodent poison down.

Case Study: Rodent Infestation in Westminster

This particular hotel in Westminster was suffering extensive rat activity at car park level and washing machine room level. Also, the linen room was being affected by mice activity, and droppings would be found on top of the stored sheets.

The hotel was being serviced by two other pest control companies who would not do proofing. Despite visiting the hotel and placing whole wheat bait, the activity would not go down. In one instance, a member of staff got bitten and had to get a shot.

When we got involved, the first thing we did is to place Deadline rat bait at the tube station ventilation system outlet level. The bait was completely eaten after three days. We kept on replenishing, and it took about three weeks before the rat population was depleted. From there, the hotel managed to have the old bed/broken beds picked up from the council.

We also carried out the proofing in the linen room and at the back of the washing machine.

The benefits were instantaneous. The staff would not be afraid anymore going to the washing machine, and the bed linen would not be soiled. The car park, at last, was cleared of rubbish, reducing further the available harbourage for the rats.

When approaching a rodent infestation, it is vital to put in place a fully integrated pest control strategy. Killing the rodents is only a part of it; you also need to change the environment to make it less hospitable for pests and change the behaviour.

Rodent control checklist

If you suspect rodent activity around your house or inside your home, the best approach is to seek advice from professionals or contact us here. If you decide to do a roof conversion or build a house extension, always consider the need for inspection hatches. Rodent control should be an inherent concern for architects, builders, and homeowners.