The ‘Petite Montagne’ of Jura extends over a particularly interesting sector from an ecological and biological point of view. As such, it is protected over a large part of its area within the framework of the Natura 2000 Network, of which nearly 63% of the territory is made up of the Valouse watershed, a right tributary of the Ain. This Natura 2000 site is crossed along a North-South axis, by the Suran, Valouse and Ain valleys and includes the En Sapey plateau, with characteristics similar to the rest of the 'Petite Montagne'.