Going to Arpenaz waterfall via the Ilettes lakes

4 points of interest

• 

  

  Fauna

  Unexpected dangers of bread

  Ah, the infamous act of throwing bread to birds!.. There's always someone who tries to win the ducks' hearts by throwing bread at them as if they were the pond's celebrities. Bread is hardly an ideal treat for our beloved ducks, or any other wild animal for that matter. It will bloat in their stomachs, causing severe digestive problems and providing them with a useless nutrient that is harmful to their growth. Weakening their immune systems, ducks develop diseases. These include the notorious duck flea, but above all "angel wing": a disease that causes malformed wings, rendering ducks unable to fly at all.

• 

  

  Geology

  Rock folding

  The Arpenaz waterfall is the 3rd highest waterfall in France (270 m) and has been classified as a protected natural site since 1991 due to its geological importance. Rock folds deforming the geological structure can be seen around the waterfall and on the mountain range above the Ilettes lakes. These are known as schists, representing a type of rock rather than a specific type of natural stone. The schist rocks include irregular, textured and layered rocks. These folds are witnesses to Alpine orogenesis: the collision of tectonic plates that created the Alps.

• 

  

  Fauna

  Duck flea

  Swimmer's itch isn't just caused by ducks! Known as trematodes, the parasites responsible for this illness are found in the form of swimming larvae called cercariae. The parasite requires two hosts in order to develop. The first is the duck, while the second intermediate host is a freshwater snail from the gastropod family, called a limnea. The parasite cannot survive on its own without any of these hosts. Humans are merely an accidental host in this complex cycle. Before dying, the parasite causes a mild but unpleasant skin reaction. Taking a shower just after swimming reduces the risk.

• 

  

  Lake

  Man-made lake and a motorway

  The construction of the motorway in 1974 led to the creation of a man-made lake. In 1977, the Ilettes lakes were formed on the location of a former excavation site where the materials for the motorway had been extracted. This construction contributed to the “artificialization” of the land, harming the quality of groundwater and altering the natural water cycles and the local ecosystem. However, the creation of these lakes also serves as a balancing measure, with the creation of a fishing reserve, a leisure centre and a benchmark for biodiversity in the third lake.