The indicator, based on data processed within the Carta della Natura project, shows the distribution of Ecological Value (VE) across 17 Italian regions, providing a representation categorized into different classes. Ecological Value is understood as a synonym for natural significance and is calculated—starting from the regional habitat maps—for each mapped polygon, excluding those referring to built environments and fully urbanized areas. This indicator offers an overview of the environmental mosaic within various regional contexts, highlighting high-value areas, including their protection status. The analysis presents the percentage of protected areas in each region and the composition of protected and unprotected zones in terms of Ecological Value. The protected areas system (EUAP areas, Natura 2000 sites, and Ramsar areas) covers territories characterized by the highest Ecological Value classes but still leaves significant portions outside protected areas.

The indicator provides an overview of the health status of common migratory passerine bird populations in Europe through an assessment of their resilience to climate change. The increase in spring temperatures due to global warming causes an earlier seasonal onset of vegetation and, consequently, of the insect peak. As a result, if migratory birds do not advance their arrival at breeding sites to the same extent, they fail to encounter an abundance of prey at the critical time for feeding chicks. A failure to advance migration timing therefore translates into low resilience of migratory populations to climate change, with negative consequences for their survival.

The analysis focuses on the temporal variation in the arrival dates of migratory passerines at stopover sites used after crossing the Sahara and the Mediterranean Sea during their spring journey from Africa to European breeding grounds. Based on an analysis of the migration dates of 10 bird species recorded at 26 ringing stations participating in the ISPRA Small Islands Project from 1988 to 2024 (37 years), it is observed that 60% of the studied species show a migration advance that is too slow (about 1 day every 7+ years) to be considered sufficient to offset the effects of climate change.