Ayeres' big loop
La Maison de la Réserve
The placid Ibex
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.
Golden Eagle 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!
The mont Blanc
These two so-called crystalline rocks come from the core of the Earth in fusion.
The history of Plaine-Joux
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.
The Common Minnow and the Common Chub
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.
The common Toad
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 !
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.
The Grass Snake
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!
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.
The alpine cabin
The history of the Passy nature reserve
The national nature reserve of Aiguilles Rouges was created in 1974, and a few years later in 1977 the Sixt-Fer à Cheval / Passy nature reserve.
A small territory, settled between these two areas, will become the nature reserve of Passy in 1980.
Architecture of mountain pasture chalets
Construction features at high altitude are strongly related to the immediate surroundings: stones for the walls, basic – but resistant to winter conditions! – framework made out of spruce.
Originally, the roof was covered with ‘tavaillons’, a kind of wooden tiles.
These buildings, used for agricultural activity during the summer, were of rudimentary comfort and housed the shepherd and its owner’s family.
The Downy Birch
In the reserve, birches are monitored as part of the "Phénoclim" program implemented by CREA and intended to measure the impact of climate change on plant cycles.
The Mountain Ash
The fruits can be used to make to make brandy, jelly or jam. But be aware that they are toxic at maturity, so you have to pick them earlier!
In the nature reserve, the Mountain Ash is part of a participatory science program intended to measure the impact of climate change on the ecosystems of the mountain.
The whistled language of groundhogs
Always vigilant, standing up, it surveys its environment to avoid to be caught. Thanks to a very wide field of vision, and excellent hearing and smell abilities, nothing goes unnoticed. In case of alert, it warns the others with an alarm call: very high-pitched and brief for a danger coming from the sky, whistled and repeated for a danger on the ground. And that danger may be you!
The Hazel Grouse
It is much less known than the Black Grouse or the Rock Ptarmigan because it lives exclusively in the forest!
But it is as important as the others from a biological and scientific point of view: it is an indicator species of environmental changes. Its specific demands in terms of vegetation and diversity of tree species ask for an adapted forest management. Bad preservation management of this habitats is one of the main causes of regression of the species.
The Black Woodpecker
It is easily recognized by its entirely black plumage enlivened by a bright red spot, limited to the nape on the females and more extensive on the males.
The Golden Eagle
The Common Raven
Alternately feared or venerated, it is the hero of myths and legends in many cultures. Persecuted for a long time, it is now protected. The size of a buzzard, it can be specifically recognized by its diamond-shaped tail and its hoarse call. It is an omnivore, which means that it feeds on carrion, eggs, chicks or berries!
The couples, which are united for their life time, carry out aerobatic courtship rituals! Apart from humans, the Golden Eagle is its only predator.
The Griffon Vulture
This bird lives in colonies of different sizes, the closest of which are located in southern Vercors. Especially the young individuals who explore new territories. To feed, this bird is also able to cover hundreds of kilometers thanks to its gliding technique, depending on favorable weather conditions.
The mont Blanc before mountaineering
View on Le Dérochoir
These various landslides created a passage making it possible to cross the Fiz ridge.
- Take the paved road to Lac Vert.
- Take the track on the right between the treehouses.
- Follow the direction Lac Vert.
- Take the paved road to the right to Lac Vert. Beacon 93.
- Take the track to the Châtelet d'Ayères refuge. Beacon 159
- Stay on the track to the Châtelet d'Ayères refuge.
- Take the track on the right to the Châtelet d'Ayères refuge. Beacon 95.
- Pass the refuge and head to Col et Lac d'Anterne, Lac de Pormenaz. Beacon 161.
- Stay on the track to Col et Lac d'Anterne, Lac de Pormenaz. Beacon 162.
- Stay on the track to the Chalets du Souay, Lac de Pormenaz.
- At the Souay chalets, stay on the track to Châlets des Ayères des Pierrières. Beacon 97.
- Take the direction of Châlets des Ayères des Pierrières, Plaine-Joux. Tag 121.
- Cross the hamlet of Châlets des Ayères des Pierrières.
- Stay on the track to Plaine-Joux. Beacon 17.
- Stay on the track straight ahead to Plaine-Joux. Beacon 16.
- Stay on the track straight ahead to Plaine-Joux.
- Stay on the track straight ahead to Plaine-Joux. Beacon 103.
- Head to Maison de la Réserve Naturelle. Beacon 102.
Access and parking
Parking at the entrance of the station.
Bus line L85 (SAT Mont-Blanc).
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