The grass snake (Natrix natrix helvetica), with an adult size consisting of between 50 and 140cm, is the least rare and the largest snake in Wallonia. Its neck is adorned with a yellow, sometimes white, collar and its sides are marked with little black vertical lines. The light coloured belly is decorated with black checkerboard speckles. This grass snake is our fauna’s only oviparious snake and is totally harmless to humans. Cornered, it can adopt an intimidating attitude or play dead. Another strategy consists of projecting a foetid and repulsive liquid contained within its cloaca, a kind of small pocket situated at the base of the tail, in order to distract its aggressor, giving it time to seek out shelter. It frequents very varied milieus, but ones which are not too far from each other so that its different needs are met.

The smooth snake (Coronella austriaca), viviparious, is a lot smaller than the grass snake, with a length of from 50 to 70cm. It owes its name to the fact that its dorsal scales are smooth, in other words devoid of a carina, unlike other snakes. It is recognised by a dark line which adorns its head, running from the snout to the neck, and crossing the eye. Its neck is also covered by a large black marking in the shape of a crescent. It is less widespread than the grass snake because very selective about its habitats. In effect it has a liking above all for warm and dry milieus, just like the common wall lizard. It is a sedentary and very secluded snake which counts on its mimetism to not be spotted.

The common European adder (vipera berus), viviparious, is our fauna’s rarest snake. It is only present in the extreme south-west of Wallonia, with a size equivalent to the smooth snake (50 to 70cm). Its head is triangular with a flattened and slightly snout. Its back is decorated with a continuous dark brown zigzag and its stomach is cream coloured. The top of its head is frequently marked by a pattern in the shape of a V, not be confused with the yellow collar of the grass snake or the black crescent of the smooth snake. The shape of the pupil is vertical, unlike the two other above mentioned snakes, which have a round pupil. Very sedentary and very loyal for several years to its living spaces, it frequents very varied milieus which are little frequented by humans. The only poisonous snake in Wallonia, the common European adder very rarely bites and does so only when it can do nothing else to protect itself. Furthermore its bites rarely have serious consequences, being restricted to local symptoms characterised by a painful swelling surrounded by a red blotch.

Whilst the indigenous reptiles are all protected by Nature Conservation legislation, the populations have been regressing for several decades and are threatened with extinction. Thus the sand lizard, common European adder, the common wall lizard, the grass snake and the smooth snake are strictly protected as their populations are considered vulnerable or even in real danger as far as the first two cited are concerned. It is even forbidden to catch them, kill them or intentionally transport or disturb them. And for the species most in danger, the banning extends to the habitats as it involves a ban on damaging their reproduction sites, hibernation period areas or any natural habit where these species live at any stage of their biological cycles. The need to understand the needs of the reptiles in terms of habitat and environment in order to put in place effective protection measures will thus be readily understood.

What habitat do they have a liking for?

With this constant need to regulate their temperature, to find their food and to flee their predators, it will be easily understood why these reptiles need available a diversified environment offering hiding places, shaded areas and open zones and why they are so sensitive to changes in their environments.

Each species has demands as to the habitats it frequents. Certain of them, such as the slow worm, are more ubiquistic and encounter each other over a wide range of habitats, from pasture lands to the forest, from gardens to rocky areas. But the majority are more selective and only meet up in warm and dry milieus. Our reptiles are predominantly species of the edge or border areas, and other transition milieus such as scrubs. Certain species require the presence of several life areas with very distinct characteristics which will be exploited in different ways depending on the seasons. These habitats have to be close to each other and must not be separated by difficult to cross obstacles such as a road with heavy traffic.