JoAnn, I've got lots of different kinds of crocuses and have noticed some are more attractive to rodents than others. The little C. chrysanthus varieties (often called snow crocus) must be delicious - those frequently get eaten. But I've found C. tommasinianus (tommies) and C. sieberi (Tricolor and Firefly) are rarely nibbled.
I've also found the large flowered C. vernus cultivars aren't nibbled very often. I think because they bloom a little later when things are starting to grow and there is more leafy food available.
I have crocuses in the garden and in the lawn and those in the garden are more likely to be eaten than those in the grass. Those in the lawn are scattered here and there and are somewhat camouflaged by the grass- maybe that's why they miss those. Those in the garden are more clumped together, so maybe they're just being efficient and gorging while standing in one spot
