The Viperine snake is the smallest of the couleuvres to be found in France and they rarely exceed 60 or 70 cm’s although females may possibly grow to 1 metre. They are frequently mistaken to be one of the different vipers to be found in France, hence its name from the French "Vipére". Their head is clearly distinct from its body, wider with flat top and sides, rather pointed nose and eyes with round pupils! At the back of their head are two lines, which can be clearly seen, in the form of a "V" the open part of the "V" at the rear although this may vary a little. Its colouring is extremely variable, olive greens, greenish brown, yellowish brown, greys, yellowish orange and reddish browns. On its back are two rows of dark lines, angled backwards, which are often joined together to give the impression of a zigzag pattern. Some may present with a more spotted appearance.
They can be found throughout most of France except the very North & North East where their preferred habitat is rapidly flowing rivers and streams. In France this is particularly the Tarn and the Jonte in the Cévennes, but they will also be found in lakes, slow rivers, ponds and in other waters that have sufficient aquatic life to support their diet. This is principally made up of fish but all manner of aquatic life will be taken including frogs and newts. They can consume vast quantities, sometimes eating fish more than a quarter of their own size.
They are diurnal and are excellent swimmers staying underwater for a considerable length of time. Otherwise they can be seen sunning themselves by the waterside. In case of danger they slip away rapidly and silently, but when they are threatened they adopt a very similar intimidating pose to a Viper hissing loudly and jerking their heads in the direction of the threat and will even strike, but with their mouth closed. They will also emit an unpleasant scent from their anal glands.
They are a snake that often scares people when they see them in the water when they are paddling or bathing but they are completely harmless.
Their period of hibernation is from October until March/April either alone or in the company of other snakes, in a hole or beneath a pile of rocks. They are also incredibly resistant to cold surviving temperatures of minus 15 C. Coupling takes place in march/April, followed by laying of between 5 and 15 (sometimes 20) eggs in July in moist soil or an abandoned hole in the ground. After 4 to 6 weeks the young hatch out.
Populations in decline due to habitat loss and pollution from Domestic & urban waste water, Industrial & military effluents and Agricultural & forestry effluents.