Control a rat infestation & control a mouse infestation are not same

We might think that rats and mice differ only in size. However, due to their different behaviors, controlling a rat infestation is not the same as controlling a mouse infestation . Unlike rats, these tend to settle and nest indoors. This, coupled with their tendency to feed on very small amounts of food obtained from various sources, requires a rat control strategy different from that of a rat infestation.

Why is controlling a rat infestation not the same as controlling a mouse infestation?

If we ask the staff that maintains the subway facilities which pest is more complicated, rats or mice, the answer will be rats. If we ask someone in the food industry or a pest control professional the same question, the answer will almost always be mice, and more specifically the house mouse.

But, in any case, to put an end to them, we will need different rat control strategies.

The rat visits, the mouse settles

Unlike rats, which tend to be casual invaders indoors, mice, once inside, want to stay indoors, enjoying the food and shelter they find there.

This behavior is not just a preference, but a capability that mice possess and rats do not. Rats need a source of water on a daily basis, without which they will not survive; for this they enter, feed and leave. Mice, however, can often survive on the moisture content of the food they eat and therefore do not need to maintain that escape route or move for water.

Big eaters or small bites

Feeding behavior also differs. Rats are by nature neophobic, distrusting everything that is new, for example our baits, but once they overcome this fear they will eat large amounts of food from the same source.

Mice, on the other hand, being innately curious, will investigate baits immediately but will typically ingest only very small amounts of a single food source, preferring to obtain their daily diet from many different sources.

Therefore, putting down one or two points of bait for mice will not solve the problem since they probably won't eat a lethal dose. Against house mice it is vital to place many baits, containing a small amount of rodenticide, with the aim of achieving the lethal dose through small shots from various points.

The situation of the baits is also crucial. Mice are acrobatic climbers and once inside the building they will quickly spread everywhere. So the rat control strategy should contemplate all levels of space; false ceilings, cabinets, above beams, ceiling cavities, etc.

The house mouse eats only about 3g of food per day, perhaps for this reason it maintains its sporadic feeding behavior, since they need to feed from several places if they want to obtain a balanced diet. They like variety in their food and are especially attracted to fats and sugars.

Rodenticide resistance

As we have seen, understanding and exploiting the behavioral characteristics of the house mouse is necessary to achieve rate control. But effective biocidal products are also needed, and here we encounter another problem.

The house mouse has shown significant levels of tolerance to first-generation anticoagulant rodenticides since its inception. As early as 1961 it was recognized that warfarin failed to mouse control.

The introduction of newer first-generation anticoagulants; difacinone, chlorophacinone and coumatetralil, did not produce improvement. With the first second-generation anticoagulants; difenacum and bromadiolone, introduced in the late 1970s, had good initial results but there were still cases where complete eradication could not be achieved.

It was not until the advent of brodifacoum and flocoumafen in the 1980s that total house mouse control became realistic for certain jobs.

Restrictions on the use of anticoagulants

Although high levels of rat control can currently be achieved by anticoagulant rodenticides, excessive or inappropriate use of these biocides has a potential negative impact on health and the environment, with unacceptable contamination in non-target mammals and birds of prey. .

For this reason, European legislation has been imposing restrictions on the use of anticoagulant rodenticides, restrictions that mainly affect the rat control, in which the placement of baits is carried out predominantly outdoors. Since house mice live almost exclusively indoors and baits for them are also indoors, neither rodenticide nor mouse carcasses present the same level of risk to wildlife as rats.

In any case, the rat control technician must be able to select the rodenticide product that can really eradicate the infestation, and know how and where to apply it.

Also, keep in mind that the use of rodenticides for mice control is not the only solution. Whether controlling rodents in domestic, commercial, or agricultural settings, you need the knowledge and skill to prevent them from entering your facility. And if we already have them inside, we will find a way to limit their access to the resources they need to survive and we can apply non-chemical rat control options, such as traps.