A walk around Lac Vert

The exhibition an information office Maison de la Réserve naturelle de Passy is located in Plaine-Joux and welcomes you during the school holidays. The permanent exhibition about fauna, flora and landscapes will open the doors to the nature reserve. You may find answers to some of your questions here and can admire the wild species hidden in nature. If the Maison de la Réserve naturelle is closed, don’t worry, go up to the passageway. There is permanent free access to information about former (geological times) and present landscapes, the wonders of biodiversity and the great challenges of the mountains of the future (water, glaciers, global warming...).

The Ibex is not very shy, especially compared to the Chamois sharing its territory.
Unlike most other mountain species, it remains at altitude even when winter and snow arrive.
It then reaches ridges and snow-cleared areas where it will more easily find grass to feed on. This search for food costs a lot of energy. So, if you see it, do not approach and let it leave quietly in order to avoid wasting its precious energy, especially in winter.

In their nest perched against a rock wall, two chicks will soon emerge from their eggs. Only one will survive: the weakest one will be killed by the strongest! In biology, this behavior is called "cainism".
This phenomenon is common for diurnal raptors, since it is part of the species survival strategy: selecting straight away the strongest in order to increase its chances of reaching adulthood. For the parents, it's indeed a great job to feed a voracious juvenile which, from 100g at birth, must reach 5kg by the time it starts flying!

Beneath the snow and the glaciers, two main rock types form the Mont-Blanc Massif: the sharp edges and the highest peaks are made of very hard granite (from the left to the right: Aiguilles de Chamonix including Aiguille du Midi, Mont Blanc du Tacul, Mont Maudit, summit of mont Blanc) while the rounder - because softer - parts are in gneiss (from the left to the right: Dôme du Goûter, Aiguille du Goûter, Aiguille de Bionnassay,...).

These two so-called crystalline rocks come from the core of the Earth in fusion.

From forest to mountain pasture, Plaine-Joux has not always been a ski resort as reflected in its name, which would mean "forest on a flat space".

As early as the 1930’s, the inhabitants of Passy were already practicing ski activities in this location enjoying a magnificent panorama. It was around 1965 that it officially became a communal ski resort. Even nowadays, Plaine-Joux remains, as well in summer as in winter, a popular family resort for skiing, hiking, paragliding... and contemplation.

Minnows are very common in highly oxygenated waters. Its presence in high altitude lakes is due to trout fishing activities. Used as bait by fishermen, it colonized these mountain lakes.

The Chub is a rather large fish, very widespread in France. It is an omnivore, which means that it eats everything. In many European countries, especially in the east, it is of highly culinary interest.

Kissing a toad transforming it into a charming prince is a myth! You must not touch this protected species, which is sensitive to diseases that humans could transmit.
But you can look it in the eyes to observe its horizontal pupil and its orange iris. You will also notice its parotid glands on the back of its head. They are used to secrete a venom, the "bufotoxin" intended to keep away any possible predator.
The toads and frogs are not the same species; toads live mostly in the forest, out of the water, joining it only during the breeding season !

This amazingly colored lake was probably formed by the landslide of the Dérochoir rock (Fiz ridge to the north) in 1471.
There are several explanations for its emerald green color, including the surrounding vegetation consisting mostly of spruces, which are reflected in its waters. But the presence of blue algae or cyanophyceae in the lake is also a probable cause.
The water comes from sources providing the lake by its surface and underground.

Semi-aquatic, it mainly frequents wetlands but also drier environments hosting its main prey, such as amphibians (frogs, toads, salamanders or newts).
It's a protected species, like all reptiles!
It can be identified by its round pupils, its olive grey color and its double black and white or yellow collar shaped pattern. Or by another special feature: when it feels in danger, it spits out a foul smelling liquid and pretends to be dead, revealing its two-colored piano pattern on its ventral surface!

Odonates, more commonly known as dragonflies, are insects.
There are two stages in their lifecycle: a "larva" (or nymph) stage which is aquatic followed by a terrestrial stage, when the adults are grown to adults.
Dragonflies are predators: they are carnivores that feed on different types of prey depending on their stage. They eat other insects as well.
Their distribution is strongly linked to climate conditions and any change has a strong impact on their presence. Destruction of their wetland habitats is one of the main threats to dragonflies.