Sacre — Monitoring program for common breeding birds — Euskadi Nature Information System

The main objective of this program is to obtain the evolution of the population of common birds in breeding season. Birds are excellent indicators of the state of biodiversity, not only because the trends of their populations integrate many ecological factors but also because they are present in all habitats, are very sensitive to environmental changes and are generally easy to sample. This is a programme that works at European level. Each country provides the indicator for each species or group of species and thus obtains a European rate of change for each one. SEO/BirdLife coordinates this statewide bird tracking program.