Thank you for your information Walter. It actually IS caterpillars!!
I was having a good 'root' through the ivy today and found what looked like an empty caccoon. So I pulled the ivy back a bit further and saw this catterpillar. I gently took the caterpillar out of the bush and put it on the table and as soon as I put it down, it did a dropping. Right there in front of me!
There is absolutely no doubt that this is what has been doing the droppings. There must be loads in there!
I'd be interested to know what kind of moth they are (presuming it is a moth?) I dont suppose anybody knows?