Going to Gers lake from Samoëns

It is the largest of the 8 woodpecker species found in France. It is a cavernicolous species, meaning that it digs cavities in trees to build its nest and lay its eggs! This is known as a "lodge". These lodges are often reused by other species, known as "host species", whether they be birds, such as the small mountain owls (Little Owl or Tengmalm), or mammals, such as the Pine Marten, a mustelid, cousin of the Weasel. Although this species is not endangered, it is important to keep this bird in mind when doing forestry work (avoid building sites when it is breeding). The depletion of dead wood and senescent trees in forests is threatening its habitat.

The effects of climate change, water shortage and repeated droughts are weakening trees, particularly spruces and firs. Despite their ability to gradually adapt to the water shortage, several tree species are increasingly dying out. Trees regulate their transpiration by closing the stomates ("pores") in their leaves, thereby curbing their growth. This closure leads to overheating, which can be fatal for the species. Trees, already weakened by these factors, can no longer fend off attacks from parasites. Certain insects (bark beetles) dig burrows under the bark of spruce trees, feeding on the wood and sap, further exacerbating the death rate with alarming intensity. Attacked trees can be identified by the change in colour of their needles, which turn from green to brown. The rate of migration and adaptation of trees (which live for more than a hundred years) is too slow to keep up with the pace of change. Forest managers are experimenting with planting species that are more resistant to climate change.

French forests are facing numerous challenges related to climate change, which are affecting their vitality and productivity. To ensure their long-term survival and versatility, management actions are carried out by forestry experts. They are carrying out clear-cuts or sanitation cuts. Although the general public sees these actions as massive deforestation, they are actually necessary in order to : - curb an epidemic of bark beetles (insect pests) that spread over a forest area in a very alarming way. -combat fires that tend to happen in areas with dead dry wood - reuse the precious wood locally (heating, construction, toilet paper, etc.). Each forest is different, and each management decision has to be taken on the basis of a number of parameters: surface area, species, neighbouring forests, global warming, the owner's requirements, the impact on the landscape, the environment or the economy, etc. The decisions to carry out these operations therefore lie with the owners. In France, 75% of forests belong to private owners. The regulations governing forestry joint enterprises and legislation remain unclear, despite requests for logging permits and regional development plans. When you enter a forest on a signposted trail, the absence of any signs (you would have seen the signs in a national forest) means that you are in a private forest.

The dangers facing high-altitude lakes are both local and global. At the lakeside, limiting noise pollution or littering is a given in view of such natural splendour. But other positive actions also help to protect the banks and the water. You should avoid treading on the banks by staying on the trails and limit direct pollution of the water (sun cream, or bringing invasive or parasitic species on the buoys). Last but not least, swirling sediment from swimming has a detrimental impact on the flora and fauna of these lakes. The thermal conditions in these environments are extreme, and each species' regrowth cycle is particularly slow. Admittedly, it's a real challenge to dare to swim in a high-altitude lake, but when you swim in a lake too often, you will invariably negatively impact such a beautiful lake. We're counting on you to be thoughtful and help protect these beautiful lakes!

Lakes are evolving ecosystems. They form and then dissolve over a long period of time. In fact, most lakes are bound to fill up and eventually disappear, as a result of slow, gradual processes of sediment deposition. The rate of filling varies from lake to lake. It depends on the amount of sediment input and the nutrient content of the water. Nutrient enrichment of lake water can be accelerated by human activity. Recreational activities such as camping and swimming bring in large quantities of organic matter, which gradually degrades the natural state of the lake.