The Rioumajou and Moudang valleys have been designated Natura 2000 sites.

For its originality, its flora, its fauna, its pastoralism, its forests, its activities of tourism and leisure activities, the site of Rioumajou and Moudang, situated on 2 municipalities of Saint-Lary Soulan and Tramesaygues, was held as site Natura on 2000. In all, 9500 ha are so dedicated to the conservation of the ecological wealth. This natural environment while sheltering remarkable, rare and characteristic animal and vegetable species, which makes the wealth of a destination as Saint-Lary Soulan intended for the lovers of an intact and protected nature.