The Way of the Vaz

TROUT

The “Torrent des Moulins” river is home to a particular variety of brown trout (Salmo trutta morpha fario) which settled in the Haute Isère river basin 10,000 years ago, following the melting of the glaciers. The section of river running through Le Vaz has an important plateau, which serves as a breeding ground for this type of trout. During the spawning season (October to November), the females dig furrows into the gravel on the riverbed and lay their eggs inside. Once the males have fertilised the eggs, the females cover them over with gravel. The incubation period lasts all winter and the alevins, or spawn, emerge in April-May when the stream’s ice and snow melts. Much of the spawn travels downstream and is scattered along the length of the waterway. Once the fish reach adulthood (3 years of age), some of them manage to travel upstream and make it back to the original breeding ground to reproduce, replenishing the native trout stock. Unfortunately, natural selection is very harsh, and out of 1,000 eggs only two fish survive to adulthood and go on to breed.

ITINERARY

Go through Le Châtelard village, past the former school building, and head towards Le Vaz. As you leave the village, you will pass a water trough on your left. Continue down the path and cross the bridge over the Torrent des Moulins stream. Just after the bridge, the path heads upwards and you will come out into Le Vaz hamlet. Turn left just before you reach the water trough and picnic tables. Once you pass the last house, go under the Petit Bois chairlift and you will get to the La Planche bridge. Have a break on the riverbank and enjoy the tranquil surroundings. Take the same route back to Le Châtelard.