Biological inventories were carried out in 2020 by Ecofirst on the sites where actions were implemented during the LIFE Elia-RTE project (2011-2017) as well as on new sites restored in the context of the "LIFE2" (after 2017). Several taxonomic groups were targeted: plants, bats, butterflies, odonates, orthoptera (crickets, grasshoppers) and a special focus on dormouse (small mammal). These inventories aim to characterise the evolution of natural habitats and populations of animal and plant species in order to highlight the effects of actions and changes in management practices resulting from the LIFE project. This report gives an overview of the sites worked during the LIFE Elia-RTE project from the point of view of added value in terms of biological diversity. It aims to assess whether the investments made have had or can still have beneficial effects on biodiversity.