Are litter snails rare this year?

Is it just me or is it becoming harder to find small snails like Carychium, Euconulus, Acanthinula, Punctum, and perhaps Vitrea spp and Aegopinella pura when sieving litter in the field in June? Perhaps this year it is simply a hangover from the dry Spring. Quick checks at Siccaridge Wood (SO/93-03-) and the adjacent disused canal on 6, 11 and 13 June, and at Highnam Wood (SO/77-19-) failed to produce Carychium. I don't think that this is entirely due to my eyesight. In most cases there was no sign of shells in the litter, or many other invertebrates for that matter.

Does the Conchological Society hold data from reasonably thorough repeated recording from the same site extending over 10 years or more?