Predated Mallard Clutch?

This morning on a sheep track near Two Bridges I found this clutch of egg shells, presumed to be Mallard (60mm long and duck egg blue) in a neat pile.  They all appeared to have been bitten through, maybe by a fox?  It's clearly not a nest as there's no down.  Could a fox carry four together?  Or why would it make four separate trips to exactly the same spot before eating them?

Posted May 24th at 10:45 pm by Chris Marcol in General Birding