The message
from Jim Lesurf contains these words:

It is certainly possible that it is something other than a cat/cats. This
was why I was using 'cats' (in inverted commas) and worded my initial
posting as I did. The puzzle, though, is what is it, if not a cat?

The evidence I had until shortly ago is as follows.

The distruction tends to occur overnight.

I have seen blackbirds pecking at the mulch, turning it over looking for
insects/worms. However they seem to attack relatively small areas, and
stand near where they peck. Hence having watched them peck over another
area where I have cocoa mulch but not membrane, I felt it doubtful they
would be able to lift and fold back such large areas of membrane, and do so
much damage in one night.

Hedgehogs?

--
Rusty
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