Well not quite....
Every year swallows nest in the feed shed - one either side of the beams and another in the corner opposite. This year however a wren has decided to 'go green and recycle ' !!
She is using one of the nests as her own, adapting it by 'recycling' the material from the other nest to construct the roof.
What the swallows will make of it I have no idea. Hopefully they will still nest in the building. Why they do I'm not sure, as it is constructed of iron sheets it gets very hot (we place insulation on the roof outside to prevent them over heating) and I am frequently in and out of shed for various things, so they are hardly left in peace, but it must suit them.
Photo: Recycled swallows nest ....now a wren's