[jpoyner]

I have a Robin in the garden which inserts in to its song a sudden, but perfect mimic of a Swallow alarm call. The bird is so good at it that for several days I was constantly looking for this mysterious Swallow overhead. I finally investigated and traced it to this Robin. Whats more is that the sudden burst of call sends the other birds scattering from the lawn!
I am intrigued on several accounts. Firstly I have never heard a Robin mimic this well, secondly it seems that this may well be used as a method of enforcing territory, sending other Robins scattering. It is holding a very strong territory and has been repeating this song for some weeks now.
Certainly have never read of this behaviour before, would be interested if anyone else has come across passerines using mimicked alarm calls to this effect?

John.