Almost every year, some birds of this particular species stop in Brittany along their migratory path. I don't know if they are endangered - still need to do some research - but, this year, I only ever saw one female in my garden. The bird on my picture is a male, with very bright colour, whereas the females are quite dull but very cute, too. Compared to, let's say a Greenfinch, the Serin is about half the size.