Birds are a fundamental part of ecosystems and there are fewer and fewer. On Europe the crash reaches 400 million of specimens in the last 30 years. In North America, the drop has been 3,000 million of birds since 1970 (30%). Some specific species are those that bear the bulk of the problem. Only 36 varieties account for 90% of those 400 million losses in Europe. And Spain is no different: 26 of the 114 most common types of birds have been left without a third of their population since 1998. The fall adds up to about 95 million birds, especially in the countryside.