I am sure that you have already seen a lot of post about Stripygoose's project The 365 Birds Migration. I should have written long time ago, because this postcard arrived on 24 May. Only ten days after it was posted in Raynes Park (London, the UK)... along with other 364 birds! 14 May is the International Migratory Bird Day.
The musical night bird was posted in the blog The 365 Birds Migration, along with the rest of arrivals. Is not this a really really amazing mail project?
It arrived wrapped in a plastic bag: