I don't think - 11. Evidence-only records (mole hills, galls, leaf-miners, etc) do not count for the competition unless the organism itself is seen or heard.
as a bare rule is a good idea, many of these are unequivocal and the possibility of confusion (and thus of course justifiable exclusion) could be cleared up by an acknowledged expert
an example is the mines (often incorrectly called galls) of Phytomyza ilicis Phytomyza ilicis (holly leaf-miner) | Natural History Museum
which are virtually ubiquitous on every holly bush or tree in (at least lowland to mid-upland) Britain; an entomologist friend who has recorded thousands of these mines has only ever seen an adult once
; or is one expected to dig out the unfortunate larva, which - other than to an expert - will look pretty much like any other Agromyzid larva, and won't prove anything.
I suppose it's a fun idea, and I am a great one for working ones local patches rather than driving for miles to 'special' spots; but I would prophesy that you won't get anywhere near 1000 unless you are doing (or getting someone else to do
) a lot of entomology and mycology . . .