Di wrote:
It is difficult to judge the size but frogs dig holes as well as
rabbits is this a poissibility? is there a pond near by?


'Don't think its frogs.
And it doesn't seem right for rabbits either. Rabbits are pretty
vigorous diggers and usually leave mounds of spoil behind. At least
mine do.
Too neat and too small for badgers.
I'd plump for rats or voles. For some reason, voles can make extensive
tunnel systems without creating the the mounds that moles create. And
voles like lots of exit holes. On the other hand a vole would tunnel
underground below the fence. So the surface level holes at the fence
make me think its more like a rat.
Or, if these are just excavations rather than tunnel systems, for
something completely different, could it be a bird? The holes around
the tree remind me of pheasant, or moorhen scratching for grubs and
seed.
'Hope you will report back when the mystery is solved. ;-)

--
ned