For those who do not know the word, the cairn comes from the Celtic karn which means “pile of stones”. They are found everywhere in the world, in the mountains, on the coast, near rivers, glaciers, or in the desert, most often on the ground but also in shrubs when the maquis is too dense. And even, it seems, in the middle of the water, in the Nordic countries where they help in navigation. A small pebble, you say to yourself that it is not a drama and that it will help other hikers to locate the path in the event of fog.
Except that today, the goal is above all to post them in photos on social networks: we found on Instagram 2.3 million publications with the hashtag #cairns, #rockbalancing (rockbalancing) 160,000 #rockstacking ( pile of stones), etc. Hence the cry of alarm launched in particular by the Calanques National Park at the beginning of the summer. In fact, these stones are there to protect the soil which is left bare against erosion and the swell which suddenly attacks even the bedrock. Beyond that, it is a whole ecosystem that is disturbed in the Calanques, such as for example a plant with small white flowers; the Sabline de Provence, which only grows in the limestone scree between Toulon and Marseille, and which is therefore protected.
On the animal side, a yellow-legged scorpion, and two small lizards: the Mauretania tarento and the verrucous hemidactyle which live in these stones. Another damage pointed out by those in charge of the Calanques: the cairn, when it becomes really huge, leads hikers to trample other shrubs, next to the path which had been drawn precisely to spare them.
More and more environmental associations are dismantling them. This is the case in Brittany at Camaret-sur-Mer or in Tenerife in the Canary Islands. At Pointe du Van on the Crozon peninsula, where things had become very worrying in 2016, the community of communes has set up dedicated spaces so that families can build their small cairns with a limited stock of pebbles. . And obviously, the phenomenon has regressed a lot.
There are fines for stones as for sand or shells for example. In national parks, fines of €135. On the beaches, since 2011: gleaning pebbles, sand or empty shells can cost up to €1,500 in fines. This is article L321-8 of the Environmental Code: if there is “risk of compromising the integrity of beaches, dunes, cliffs, marshes.” In reality, the real risk mainly concerns the resale of sand on the internet. As for live shells: the best thing to do before picking them up is to get information from the town halls.
Driftwood, cuttlebone, seaweed or sponges are not affected – the so-called sea line, brought back by the tides. Now, even if it means using Instagram, the Calanques de Marseille recommend that you launch other hashtags: like #stopcairn, or #leavenotrace. A few dozen uses so far, but everything needs a start.