Fauna and Flora

Unspoilt nature in the heart of the Grandes Rousses massif in the Oisans region

Nestling at an altitude of 1,350 m, Oz 3300 is an integral part of the Grandes Rousses massif, an emblematic area of the Oisans region dominated by high peaks, glaciers and vast mountain pastures. Between coniferous forests, flower-filled meadows and panoramic ridges, this mountain environment offers a rich and lively natural setting.

In summer and winter alike, the Oz mountains reveal a remarkable biodiversity, shaped by the altitude, the Alpine climate and the traditional pastoral practices that have maintained the balance between human activities and wild nature for centuries.

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Large alpine mammals

Chamois and ibex: agile and discreet, they roam the rocky slopes and sunny balconies, particularly visible at dawn or dusk.

Red deer, hinds and roe deer: found in the high altitude forests, they are a testament to the health of the forest environment.

Variable hare and fox: perfectly adapted to the contrasting seasons in the mountains.

Black squirrel: discreet and agile, it lives mainly in the spruce forests around Oz 3300, where it feeds on seeds and cones, playing an important role in forest regeneration.

The alpine marmot, sentinel of the mountain pastures An essential symbol of the mountains, the alpine marmot is one of the most easily observed animals around Oz 3300, particularly in spring and summer.

Living in colonies on sunny mountain pastures, they dig elaborate burrows where they take refuge and raise their young. A herbivore, the marmot feeds mainly on grasses, flowers and seeds, contributing to the natural balance of the meadows.

A life cycle closely linked to the seasons

Hibernation: from autumn to early spring, the marmot hibernates for several months, surviving on fat reserves built up during the summer.
Wake-up call in the mountain pastures: as soon as the snow melts, its characteristic whistling sounds resound on the slopes, a warning signal to predators.
Observe without disturbing

To preserve its tranquillity :

  • Observe it from a distance,
  • avoid feeding it,
  • and remain discreet and silent.

The marmot plays an essential role in the Alpine ecosystem and is the perfect embodiment of the natural wealth of Oz 3300.

Mountain birds

Golden eagles, griffon vultures and bearded vultures fly over the valleys.
Black grouse and rock ptarmigan, sensitive species, remind us of the importance of respecting protected areas, particularly in winter.

Fish in the high altitude lakes around Oz 3300

Near Oz 3300, a number of high-altitude lakes are remarkable aquatic environments, where life adapts to demanding conditions: cold water, a long period of snow cover and a low supply of nutrients.

Lac Besson

Located on the plateau of lakes, Lac Besson is one of the best known. Its cool, well-oxygenated waters are home mainly to trout (fario trout and sometimes rainbow trout), a species that can withstand low temperatures and marked seasonal cycles. These fish play a key role in the biological balance of the lake.

Lac Carrelet

Smaller and more confidential, Lac Carrelet offers a more discreet but equally interesting natural environment. There are also populations of slow-growing trout here, a reflection of the high-altitude conditions. It’s a great place for birdwatching, in a calm, unspoilt setting.

Protecting fragile ecosystems

High altitude lakes are particularly sensitive to disturbance. It is essential to :

Respect the regulations in force,
avoid any introduction of species,
preserve the quality of the water and banks.
These aquatic environments add to the natural wealth of Oz 3300 and reflect the diversity of habitats found between forests, mountain pastures and high altitude wetlands.

A thousand colours of Alpine flora

Summer pastures

In spring and summer, the meadows are adorned with :

  • gentians
  • rhododendrons
  • arnica
  • martagon lilies.
    These high-altitude flowers play an essential role for pollinating insects and contribute to the beauty of the landscape.

The mountain forest

Norway spruce: ~900 to 1800 m
Larch: ~800 to 2,300 m
White fir: ~800 to 1,600 m
Birch & ash: mainly between ~600 and 1400 m (edges, wetter areas)
They provide a haven for wildlife and contribute to the natural regulation of soil and water.

Adopting the right precautions in the mountains

To preserve this exceptional environment :

  • Stay on the marked trails,
  • Observe animals from a distance,
  • keep dogs on a lead,
  • bring in your rubbish,
  • respect the quiet areas.

The Sensitive Natural Area (ENS) of the Plateau des Lacs d'Oz en Oisans

The Plateau des Lacs d’Oz 3300 is classified as a Sensitive Natural Area (ENS) by the Isère Department. The aim of this classification is to preserve a remarkable natural heritage, while allowing the public to explore it in a way that respects the environment.

Situated at an altitude of 2100 m, this vast plateau is home to a number of emblematic lakes, wetlands, alpine meadows and high moorland. It is a veritable reservoir of biodiversity, hosting a mosaic of rare and fragile habitats shaped by water, the mountain climate and pastoral practices.

Exceptional biodiversity

The Plateau des Lacs nature reserve is home to :

a varied fauna (mountain birds, amphibians, aquatic insects, discreet mammals),
alpine and sub-alpine flora characteristic of wet soils and high altitude meadows,
sensitive ecosystems, particularly vulnerable to trampling and disturbance.

An area to discover and respect

Signposted paths and discreet facilities allow you to discover this natural site while limiting the impact on the environment. During your visit, it is essential to :

  • Stay on the marked trails,
  • Do not pick plants,
  • Respect the peace and quiet of the wildlife,
  • Keep dogs on a lead,
  • Leave no trace of your visit.

The ENS of the Plateau des Lacs d’Oz 3300 is an emblematic site of the region’s commitment to nature conservation, offering visitors a privileged immersion in the landscapes and natural balance of the mountains.