Tag Archive for: Rodents

Mus musculus

Dark to black on the upper side, gray on the underside. Body and tail each 9 cm long. High reproductive capacity. 4-8 young per litter, 4-6 litters per year. Prefers to live in dry rooms, can adapt well to different conditions, e.g. cold (occurs in cold stores). Food and animal feed, but also textiles, paper, leather, etc. are eaten and contaminated by excrement. The presence of mice on cereals differs from rat infestation in the presence of small, approx. 1-2 mm large gnawing shavings (husks, pieces of grain). Also transmits diseases, e.g. paratyphoid, trichinosis, etc.

Arvicola terrestris

The large vole (also known as the ground rat or vole rat) belongs to the genus Arvicola. It is one of the most unpleasant animal pests in the garden due to its strong feeding and burrowing activity and the associated destruction of the turf. Where there is a vole infestation, fruit trees, roses and vegetable plants wilt or suddenly topple over. They also like to eat flower bulbs, potatoes and root vegetables. In Germany there is a land form, which lives in its underground burrows, and an aquatic form, which prefers to live near bodies of water, ditches, streams and embankments.

Appearance:
Voles grow to a length of 12-22 cm and weigh between 60-120 g. The coloration of the fur varies from different light to dark brown tones. Characteristic is the blunt head with small ears that disappear into the fur and a short, slightly curled tail (approx. half body length).

Construction and lifestyle:
Voles are solitary animals that only come together during the mating season. The underground burrows are only used by a single animal. A vole burrow contains one or two nests and, in the fall and winter, storage chambers in which root pieces are stored. Voles are diurnal and nocturnal animals. They reproduce from March/April to September/October. During this time 2-4 litters with an average of 4 young are born. It only takes about 3 weeks from mating to birth. The young from spring become sexually mature in the same year. Theoretically, a female could produce up to 40 offspring a year. The lifespan of the animals is only about 2 years. In contrast to the mole, the burrow system of a vole is clearly highly oval, smooth, firm and without plant debris. The piles of earth themselves are flat, rather inconspicuous and are heaped up to the side of the actual burrow system.

Control/prevention:
For young trees, it is advisable to enclose the root ball with a galvanized wire basket (mesh size maximum 16 mm). Natural enemies of the vole are various weasel species, owls and birds of prey. Setting up perches as perches for birds of prey or piles of stones as shelters for weasels can promote their colonization. The best control periods are late fall, as long as the ground is open, and early spring. Control should be carried out over as large an area as possible. Measures during the summer months are less effective.

rattus rattus

The domestic rat has a head-torso length of 16 to 24 cm, a tail length of 18 to 25 cm, the tail has 200 to 260 rings, the weight is approx. 200 to 400 g. The snout of the domestic rat is pointed, eyes and ears are relatively larger than those of the Norway rat. The less specialized, very adaptable free-living animals are generally regarded as food pests. In addition to other small rodents, free-living domestic rats are also reservoir hosts for various types of borrelia (bacteria), which can then be transmitted to animals and humans by vectors such as ticks already found in front gardens. In contrast to Norway rats, they are much less common.

(or forest vole)

Myodes glareolus

The name red-backed vole comes from the reddish-brown coloration of the dorsal fur, while the name forest vole comes from the preference of this species for shady habitats in or near forests. This species is one of the most common mammals in Europe and is therefore not considered endangered. With a head-to-torso length of seven to more than 13 centimetres, this relatively small mouse species has a tail length of 3 to 6.5 cm and weighs between 12 and 35 grams. The species shows size and weight differences of up to 300 percent between populations in different regions. Its habitat is formed by beech and mixed forests, hedges and bushes close to forests as well as wetlands. It is also often found near watercourses. Gardens close to forests are also accepted as habitats. The bank vole also builds its nests in little-used barns, storage sheds, garden sheds or other wooden structures. Leaves, dry moss cushions and twigs that have been carried in and deposited by the bank voles provide evidence of an existing nest. Although the bank vole poses little threat as a forest pest, its droppings can transmit the fox tapeworm and the Hanta virus. The viruses also survive in dried excrement and urine and can be ingested via dust in the air (e.g. when sweeping). A protective/dust mask must be worn when cleaning infested buildings!

rattus norvegicus

Body length up to 25 cm, tail scaly and ringed, slightly shorter than the body. Upper side of the fur is gray-brown to reddish-brown in color. The belly is light gray to whitish. The limbs are short and the front and hind paws are bare and pink. Like all rodents, rats have two incisors in the upper jaw and two in the lower jaw. These are strong, chisel-like and deeply anchored in the jaw and must be used constantly, otherwise they will continue to grow. In Europe, the species is primarily regarded as a food and hygiene pest. Damage is caused by feeding on food, but above all by contaminating it with excrement and urine and by destroying packaging materials. Hygienic problems arise primarily from the spread of paratyphoid germs into kitchens and storerooms, which is a frequent cause of food and feed poisoning. Norway rats are known in Europe primarily as reservoirs and excreters of leptospires, the pathogens that cause leptospirosis.