March 16, 2014

Ciconia ciconia

Sci: Ciconia ciconia, No: Stork, Eng: White stork, It: Cicogna bianca

Dear all,
This month I post a bird after two weeks in Madrid. The White Stork is perhaps the most typical bird in Spain. In cities like Segovia (below) storks nest on the rooftops.

The Mystery of the non-migrating Storks: For ages storks have migrated to Africa in the winter. Since they need warm up-winds to fly, they cannot cross the wide parts of the Mediterranean, and must cross either over Gibraltar or through the Middle East. This is one reason why Spain has more storks than any other European country (> 30.000). Then, in the 1980s, they learned that it might be easier to stop migrating and stay in Spain also in the winter. Instead of feeding on frogs and snakes, they found 'junk food' to feed on in the garbage land fill sites. So, nowadays storks are seen in Spain also in the winter. Why this change in behaviour? Nobody knows, but it is being investigated. I believe that they just learn from each other. Learning has been observed in other bird species. Read more: Why has Storks Stopped Migraging (Science Daily).

Interestingly, the fertility rate in Spain dropped dramatically from the 1950s until exactly the moment the Storks stopped migrating. From that point on, the curve flattened, and even started to climb! Fertility in Spain.

Best regards,