Les Claux circuit (no. 4)

Humans are decidedly bizarre animals: they build, knock down and start again. To protect the new infrastructures of Pelvoux, the Gyr was dammed. But, not able to flow as it did before, it deepened its bed, thus placing the foundations in danger of damage. And so works were carried out to widen its bed, allowing it to flow more naturally. This is also more favourable for biodiversity, as well as protecting the developed urban areas.

In the valleys of the Alps and the Jura, the grey alder often grows in place of the black alder, present in many parts of France. Like its cousin, it grows on riversides and plays an important role in stabilising the banks. If it is cut down, its wood is bright orange in colour. But why cut it down?

The track passes through a meadow area, which is categorised as "cool" because of the ground water content there. A botanist quickly recognises this type of meadow through its range of plant life and, in particular, the presence of bistort, a bottle brush-shaped plant bearing a dense spike of tiny pink flowers at the top of its stem. It is also called langue de boeuf ("ox tongue" in English) because of the shape of its leaves.

The route first leads through the small ski resort of Pelvoux-Vallouise, built in 1982. Very family-focused, in winter it's the ideal place for young children to learn to ski, with small lifts lower down, while their big brothers and sisters can ski higher up.

A grass grows in large clumps on the embankment: silver spike grass. It is adapted to stony, dry and sunny ground. Its inflorescences reflecting silvery-gold glints create a beautiful effect, but they are particularly noticeable in the late summer, when it forms large shimmering bouquets in the evening sunlight.

On peut souvent observer le cincle plongeur, qui comme son nom l'indique plonge ! Puis il marche à contre-courant au fond de l'eau pour chasser des larves aquatiques d’insectes ou des petits crustacés, soulevant les galets avec son bec pour les déloger. C'est un indicateur de la présence de ces petits animaux et donc de la bonne qualité des eaux.

Du fait de divers travaux effectués au 20ème siècle, l'ancien lit en tresses du Gyr avait disparu au profit d'un lit très étroit et contraint. Cela a eu pour résultat un creusement important déstabilisant les berges, menaçant les réseaux et les infrastructures touristiques ainsi qu''un un appauvrissement important des milieux écologiques associés.. En 2018, certains travaux d'élargissement ont été menés pour permettre de limiter les dégâts de crues et d’érosion et restaurer les milieux aquatiques