I am going to participate in the elaboration of the “technical bases that justify the establishment of quantitative limits for the consideration of significant populations of species” for the Spanish Ministry for the Ecological Transition and the Demographic Challenge. This docuemnt should help the corresponding managers and the Spanish resposnables of Natura 2000 Service as a guide for quantifying the need for protection of species on Natura 2000 areas, based on demographic criteria. My specific work will consist of gathering information about the actual criteria used by all the EU state members and for The regional “Comunidades Autónomas”. This project should serve also as a first step for building a network of eurpoean demographers and get consensus about which should be the best criteria to use in all the EU and for several conservation agents and programs (i.e. IUCN).