This is an Iberian Magpie. It is often called an Azure-Winged Magpie here in Portugal, however, this is not strictly correct! Although very similar, the Azure-Winged Magpie is found in Eastern Asia. It was once thought to be the same species, however, they are different.
The Iberian Magpie is found in Central and Southern parts of Spain and Portugal and occur in large, sometimes huge flocks. I have noticed that the flocks tend to follow a similar route every day as they fly from area to area.
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