Hi Daffydil,
Yes, I go hedgehog watching in person so I can tell where the crunching of snail shells is coming from. I assume they eat slugs too but that doesn’t make much noise! I was reading an interesting article that said they won’t attempt bigger snails with a shell diameter over 13 mm or so, but the smaller ones they eat with gusto. I suspect you’re right about the nutrition value, the article suggested the gastropods are easy for them to digest, so much so that they were indistinguishable from the rest of the stomach contents unless they happened to eat a bit of shell or the horny tongue thing that slugs and snails use to eat with. Although it also seems they don’t much care for the slime- another reason why they don’t bother with the larger slugs, who seem to produce more of it? I saw some videos of them apparently wiping slugs with their feet or rolling them on the grass to remove the worst of the mucus.
