Excluding the “panthegane” (sewer mice or rats) typical of cities, there are numerous species of mouse, from domestic or common to wild or country mice, from voles to shrews. They all gravitate around areas inhabited by humans with green spaces, both outside and inside buildings and artifacts. All of them are terrified by the physical presence of man or major pets, running away quickly.
4 species of mice
The common mouse measures 20 cm, about half of which are of tail, and weighs 10-25 g; it has a short and shiny hair, from brownish to black, on the whole body, but legs, ears, tail and tip of the snout, which are almost completely glabrous and of pinkish-grey color.
The wild mouse or country mouse is about 18 cm long, tail included (about half of it), and weighs 18 g; it has pale brownish-brownish hair with ventral parts and white legs, big and black eyes, rounded ears, glabrous and membranous, and hind legs much longer than the fore ones.
The voles are 30-32 cm long, of which 11 cm are of tail, and weigh about 120 g; they have long and thick hair, silky, from dark grey to reddish brown, with presence of grey on the rump and pale belly; the head is big and rounded, with stocky and short snout, small and black eyes, small ears, semi-circular, hidden by the hair.
The shrews are 5,5-8,2 cm long and weigh 5-12 g; they have dark brown velvety hair (paler in the young) with pale belly; the head is elongated with small eyes, long, mobile and pointed nose and red toothed teeth.
What rats attack
In the garden, in addition to feeding on fallen fruits and food residues, mice can attack young woody plants by gnawing on the bark and roots. Voles prefer the roots of artichoke plants.
Inside buildings and artifacts (barns, sheds, warehouses and cellars) they seek food and shelter, nibbling on food supplies (mice and mice prefer nuts and hazelnuts, but also cereals, dried legumes and even chocolate and croquettes for dogs or cats), bulbs and tubers in winter storage, and nesting in boxes and straw, resulting in dirt.
What damage do they cause
Mice like young roots, tender bark and buds inserted at the collar, gnawing young woody plants to death. The presence of mice is indicated nearby by holes in the ground, with a diameter of 4-5 cm, which can flow into tunnels.
In the artefacts they devastate the food supplies that they contaminate with faeces, the preserved tubers that they damage to the point of rotting, and objects such as boxes, bags, straw etc. that they gnaw and smear. They require the removal of materials with which they have come into contact.
They can also contaminate the waters of tanks and ponds (and all non-current waters) with urine that can contain the leptospirosis bacterium, which infects humans and pets (dog and cat) through wounds on the skin, causing serious damage to health.
When mice do damage
Young plants are attacked in winter, because this is when they are planted, and because more food is scarce.
They can act in all seasons, depending on the availability of food.
They generally do not hibernate.
How to prevent mice
The best prevention (and remedy) is to get a cat, even a well-fed one, because it keeps the predatory instinct, or rat poison, you can check what you can afford in mouse poison reviews.
It is good to keep clean the garden, the annexed artifacts and the house, eliminating every possible food and cleaning the ground from the foliage (shelter for the animal). Check that there are no loopholes (2-3 cm) to access the interior of the house.
How to fight mice
Evaluate the choice of control system based on the presence of children or pets other than cats (dogs, rabbits, etc.). If there are any, it is preferable to use spring traps or snap traps (see later), ready-to-use adhesive traps and glues (see later), both free of poisonous substances, placing them on the routes preferred by rodents: along perimeter walls or full furniture, and on the threshold or inside burrows. Recently there are also topicides on the market based on chemical substances effective on rodents but with low toxicity for pets: in case of accidental ingestion, they should only cause drowsiness, easily solvable by the intervention of the veterinarian.
If there are no children or animals you can use traditional topicid baits, which contain highly toxic active substances on all warm-blooded animals. Tophododes should never be handled with bare hands: just use a pair of work gloves, a jar to extract and pour the pelleted lures or a stick to move them to inaccessible places. All baits must be concealed using the special safety containers on sale with the product, which prevent accidental contact. Every 3-5 days, the consumption and/or integrity of the bait must be checked and the bait must be replenished or replaced. If the bait is placed outdoors around buildings, the topicides must be resistant to atmospheric agents. The package, if not fully used, should be stored tightly closed to avoid humidity and in a safe and inaccessible place. The best results are obtained by frequently changing the type, format and composition of the topicid.
Warning: read the label carefully to use it correctly, effectively and without danger.
On the market you can also find biological baits, based on natural substances that are not very toxic: although they are less dangerous than chemical ones, it is always good to protect them too to make them inaccessible to children and other animals.
How to fight panthegane and rats
Rodents, in particular rats, are shy and suspicious animals, especially when new objects appear in their territories, such as traps, bait and bait containers. Rodents need time to become familiar with the new, especially with new food. It is therefore normal that some time should elapse after rodenticide baits have been placed before rodents start feeding on them. This suspicion of new objects is called “neophobia”.
Weather permitting, bait points (i.e. protective boxes) can be placed some time before the actual rodenticide treatment begins, using food that is attractive to rats. This can help overcome the rats’ initial reluctance to enter the bait boxes and feed in them.
When applying rodenticide baits, access of non-target animals to these baits should always be minimised, for example by using only tamper-proof bait containers. However, it has been found that rodents, especially grey rats, are reluctant to enter these bait containers and this can significantly extend the duration of rodenticide treatments.
Therefore, it is a good approach to protect baits with natural materials found at treatment sites, provided that safe, appropriate and correct placement can be made in this way. This approach is more effective, reduces the duration of bait placement and minimises the risk of primary (i.e. other animals finding and eating the bait) and secondary (i.e. other animals eating the poisoned rodents) poisoning for non-target species. In many circumstances, if natural and safe bait covers are not found, bait containers should be used.
Where to put bait for panthegane and rats
In most cases, grey rats do not live inside buildings, but come from nearby dens to find the resources they need, such as food and water, inside buildings. Therefore it is important to thoroughly patrol an infested place, both inside and around buildings, to identify signs of infestation and place bait near where the rodents are living. In this way, rodents will have access to the bait more easily, and treatments can be completed more quickly, than when the bait is placed only next to or inside the infested buildings.
Introducing an appropriate rodenticide bait directly into the rat den system can be a quick and effective method of control. Rarely will it be possible to quickly and effectively eliminate infestations by placing bait only inside buildings.
Where to put the bait for the mice
Domestic mice, on the contrary, live almost exclusively inside buildings and can generally be treated with bait placed entirely inside them. This means that, in most cases, rat control operations may pose less risk to non-target wildlife than rat control operations. In addition, mice are more curious and less suspicious than rats and have no neophobia. They easily feed on attractive bait, but do not feed constantly in one place. Therefore it is recommended to use small amounts of bait and to place more bait points in the infested areas.
It should be borne in mind that rats and mice are very prolific and that their populations can increase very quickly. In order to avoid the accumulation of large numbers of individuals, regular monitoring of sites is necessary to promptly detect rodent infestation. It goes without saying that it is easier to control a small infestation than larger, established infestations, so less rodenticide bait will be used.
Bait: how to avoid dangers to other animals
Potential exposure to rodenticide bait can be controlled or prevented, for example, by using tamper-proof bait containers or by placing bait in locked or secure locations to prevent human access. It is important that the bait contains a bitterant to help prevent accidental ingestion by at least humans.
However, it is necessary to determine the potential environmental effects and identify precautions needed to protect non-target wildlife and the environment in general. Non-target wildlife to be considered includes pets and domestic animals, other small mammals such as moles and voles, weasels, ermines and birds of prey such as kites, owls, kestrels and hawks. Primary poisoning is the most likely route of exposure by pets and small mammals. To limit this risk, baits should be placed safely in inaccessible locations to reduce access to these non-target species as much as possible.
Where possible, positioning of bait in rat holes is preferable. In addition, to help prevent the risk of secondary poisoning of birds of prey, dead and dying rodents should be frequently searched for, removed and disposed of in accordance with local regulations.
Consideration should also be given to the potential impact in the environment caused by bait dispersed or removed from bait points especially near watercourses.
Among the many different types of rodenticide formulations (grain baits, ground grain mixtures, pellets, blocks and pastes), the formulation should be chosen according to the site and type of rodent infestation. An authorised product should only be used for the use for which it is applied. All these products are sold ready to use and nothing should be added to the bait. You must then read the label and follow all recommendations for proper use printed on the label.
It is good practice to place bait and bait containers in hidden positions. Rodents feed more easily in such locations and baits are less likely to be tampered with by people or other animals. When tamper-evident bait containers are exposed in areas of public access they should be labelled with words such as: “Poison” or “Rodenticide Bait”.
Finally, while bait placement in rodent dens may be effective in achieving rapid bait consumption by the animals occupying the dens because non-target animals are unlikely to use dens occupied by rodents, frequent checks are still necessary because the baits can be taken outside and, despite all efforts, it may be difficult to retrieve unconsumed bait from inside the dens.
Snap and spring-loaded traps called “back-breakers”, which are designed to capture and kill rodents, are useful in certain circumstances. However, their use in respect of pity towards rodents and the effectiveness of the system requires a high degree of user competence and, if necessary, these traps should be placed in tunnels to avoid negative impacts on non-target wildlife, domestic animals and children.
These traps may not kill instantly; therefore they should be monitored daily so that animals caught but not killed can be eliminated humanely. Such traps may be effective in situations where infestations are limited, but are economically disadvantageous in the case of large and widespread infestations.
Glue or adhesive boards are also available which can provide effective control in certain circumstances. Like traps, however, they can catch non-target animals and birds and should be checked at least twice a day.
Inexperienced users of glue traps are unlikely to know how to humbly remove rodents caught on the adhesive surface. For this reason, the EU warns against their use.