If the Verdon is home to a fair density of trouts that delight the local fishermen, several of its fish species are however protected. Since 2012, the Rhone streber (Zingel asper) has, for example, been the subject of a Biotope Protection Decree over 10.5 miles (17 km) in the gorges of the Grand Canyon. A population of sculpins discovered in the locality of Gréoux-les-Bains also benefits from specific protection. As for the white-footed crayfish, formerly present throughout the watershed, it has seen its distribution area reduced to certain tributaries following the introduction of species that are sometimes healthy carriers of the aphanomycosis (crayfish plague).