Thanks
Interesting idea
I shall talk to the lady that did them - my wife!
It's basically hot melt glue the feathers on starting at the bottom and working your way up going round
She bought some polystyrene balls to use as a base but have also glued onto normal Christmas shiny ones, which is a good use of ones that may be old and battered.
the ones in the picture are using the 'clean' ends of the feathers but it's possible to make a fluffy/ scruffy version using the entire feather in exactly the same way...