The extraction of inert materials, with accompanying alteration of the morphology of riverbeds (enlargement and consequent increase in depth and current velocity), and the destruction of riparian vegetation make those areas unsuitable for shelter, feeding and spawning, and are particularly damaging if taking place in the spawning areas and during the spawning season of the species.
During extraction works there is still an elevated risk of water turbidity in a significant downstream area, which can lead to fish asphyxiation (due to the deposition of particles in the gills) and the colmatation of the fertilized eggs, causing significant mortality rates in all the development phases of the species.
