TRALLO the mole



INTRODUCTION.- Most people have a vague idea regarding the nature of this creature. Even scientists do not know much about the mole. That is so probably because moles spend most of their lives underground. It is very difficult to keep them in captivity because of the enormous amount of food that would be needed.

Nevertheless, thanks to the different sources of information that we have consulted and to direct observation of this creature’s activity, we believe we can conclude the following:

Moles can be found almost all around Europe, Asia, southern Africa and North America. There are not many varieties of moles (about 30 species are said to exist around the whole world) but there is a possibility that there are more, still unknown species. All of those species have similar habits, with rare exceptions in a couple of species.

Here we are going to focus on the species called Talpa europaea (common mole).

EXTERNAL APPEARANCE.- The mole does not belong to the mouse family, but to the order of the insectivorous mammals. In other words, moles eat insects.

The mole is 12 to 18 cm long and weighs 60 to 130 grams. Its teeth are sharp, similar to a cat’s. It has got a long movable snout that reminds us of a pig’s. This snout is almost completely bare except for a few hairs, from which the mole gets most of its sensory information (sense of touch). Some biologists think that moles have electric and magnetic sensors in their nose to be able to move through their dark world. The mole lives in a sensorial world ruled by smell and touch.

Its extremely small eyes (basically, a very thin membrane) are situated at the end of its snout, hidden by the fur. The mole’s eyes can only detect light.

Although moles have no ears, just a pair of holes covered by the skin, their hearing is very sharp.

The mole’s head, broad and flattened, is followed inmediately by a cylindrical body covered by a very dense soft dark (sometimes black) hair. Its hair is very special: each hair is thicker around the center than at the ends. This protects the mole from the dirt and from the water and also allows it to move freely along its corridors, because there’s no resistance in any direction.

The mole has got strong, robust front legs in the shape of a pair of paddles facing outwards. Its hands are big and have a round shape. Its fingers and nails are strong and prepared to dig into anything.

Its hind legs are longer and more simple, similar to a mouse’s. The mole uses them mainly to push itself forward while the front legs are digging.

Thanks to the specialized structure of its bones and muscles, the mole can project a lateral force when it is digging equivalent to 32 times its body weight (Arlton, 1936).

At the end of its body there is a short tail covered by hard spiky hairs. These hairs, although they are sensitive and can receive information from the vibrations that travel through the ground, are not too important for the mole.

DIET.- The mole’s diet is based on earthworms, but it also eats insects and grubs. The mole develops its activity both during the day and at night. According to current research, the mole sleeps and works at four-hour intervals. It is more active early in the morning and at dusk but that does not mean it is not active at other times, even at night, and throughout the whole year. So much activity makes it really hungry. Moles can eat 70% to 100% of their body weight every day, hence their “insatiable appetite” reputation. As a matter of fact, the mole cannot spend too many hours without eating. It stores its food close to its cozy winter nest. Since it is always well prepared (it has to), it stores hundreds of earthworms, whose circulatory system it bites. In so doing, it manages to keep the earthworm rigid but alive, unable to escape. That is how the mole has always got fresh food in case some difficult times come.

One curious fact: the European mole’s teeth are different from the American mole’s. There were no worms in America until they were brought over from Europe, so the American mole is not adapted to the new source of food yet and does not have the same storing ability.

BREEDING.- The female mole gives birth to 3 to 6 baby moles twice a year after a gestation period that lasts 4 or 6 weeks approximately. The baby moles weigh about 3.5 grams. They are born blind and with no hair. After the first 14 days of life, their hair grows and when they are 22 days old they start seeing and moving. Both the male and the female mole look after and feed their offspring (if the female mole dies, the male mole abandons them). The baby moles are suckled by their mother for one month, at the end of which they may weigh 80 grams. After two months, the baby mole starts digging by itself. They reach sexual maturity when they are one year of age. Moles can live 3 or 5 years, depending on how healty they are.

HABITS.- It is a known fact that the mole is a soltary animal. They even fight to death between themselves sometimes. If we go a bit further, we should mention Donal and Lillian Stokes’s research, described in their book Animal Tracking and Behavior (1986). Adult moles are solitary animals that avoid contact with other moles. However, there are at least two exceptions. One of them occurs when the female moles are on heat. Even after they have mated, males and females can stay quite close to each other for several weeks. The second exception is that some tunnels are used every now and then by more than one mole; in this sense, those tunnels could be compared to our roads or motorways. What Donal and Lillian Stokes say is that this communal use suggests that these animals’ social system might be more complex than we suspect. We have obtained similar information from our own experience. Sometimes, the activity has ceased when we have caught a mole in a piece of land full of signs of their activity. Some other times we have also been able to catch about 14 moles in less than a month in similar or even smaller areas.

They live underground and hardly ever come out. They like light, well drained and slightly humid ground. They build two kinds of underground corridors that are mutually connected:

Superficial (corridors) and deep (corridors)

Superficial corridors are more used during the summer, especially after a warm rain. When the mole opens and builds them (searching for food), it leaves bulging tracks on the surface (when you step on them your feet sink into the ground). Those tracks can be very long.

It is easy to control moles when they are digging this kind of corridors, if it were necessary.

Deep corridors are used throughout the year as nests and storing places. The mole usually chooses those areas surrounding the tree roots. When it is building those corridors, it occasionally takes the spare earth out on the surface. Hence those characteristic mounds that tell us there is a mole working around that place. Those mounds are also useful to let more air into the galleries.

Oken kept a mole in a box full of sand for trhee months, and he observed how the mole worked as fast as fish move through the water. Unbelievable!

Not only does the mole have an amazing sense of touch, front legs as useful as the best tool and a magical protecting skin; it also has twice as much blood and haemoglobine as other mammals of the same size, which helps it to breathe more easily in an underground environment where there is lack of oxygen and an excess of carbon dioxide (Arlton, 1936).

Therefore, this animal is adapted to underground life like no other creature. Moles abound here in Galicia (Spain) and in the north of Spain and they can be found in meadows, in gardens, in crops...

The mole does not have many enemies, among which we should name people, cats, dogs and foxes (which do not normally eat it).

It emits a soft shrieking sound that becomes louder when the mole is ready to fight.

ADVANTAGES AND DISADVANTAGES OF MOLES.-When we see some damage on the land surface, we must find out if it is actually the mole’s fault.

The mole is an insect-eating mammal, it does not eat roots or bulbs, although it is often blamed for that. Therefore, it controls unwanted insects in a clean, natural way. By digging tunnels, it changes and renews particles and organic matter, contrubuting to a better aeration of the soil.

The worst kind of damage caused by the mole, apart from the aesthetic damage in gardens, has to do with its eagerness to dig, because it ends up separating the soil from the roots of the plant and eliminates the plant’s food source. Besides, the tunnels digged by the mole are used by other animals (belonging to the mouse family) that do eat roots.

It is up to you to decide if the disadvantages are more than the advantages, if you wish to be consistent and not break natural balance.

CURIOSITIES.- The mole is often mistaken for the mediterranean pine vole (Microtus duodecimcostatus). They do not even look similar, nor do they belong to the same family, but they also lead an underground life and build superficial tunnels. However, this is a herbivorous animal that eats tubers and roots, so it may become a real problem.