Worn areas on my snails

[mylovelypond]

Hi,
can anyone shed any light on what's going on with my snails?

All the bigger ones seem to have these deep perfectlty circular areas that are worn almost all the way through the shell. (the areas on the photos that look "splodgy" are where the circles have overlapped)

I have seen baby snails nestling in these spaces and wondered if they were eating them to build there own shells.
Other than that I assume they're crop circles!



Hope someone can enlighten me,

Rob.

[The Woodman]

I've always thought thaat this activity was caused by a lack of calcium in the snails diet coupled with overpopulation.

I put a lump of tufa in my small pond and the snails are all over it. There's no shell grazing like there used to be, perhaps I overstocked in the first place.

Welcome to WAB, mylovelypond.

[Ukwildlifeo]

Interesting stuff. Ive not seen this before myslef so thanks for posting.

[tom00_uk]

snails will happily rob calcium from another snails shell if its in short supply

[Farplace]

You could try providing cuttlefish bone too. It floats, but can be weighed down. A good form of calcium for snails.

[mylovelypond]

Thanks for confirming my suspicions about the snails nicking calcium off each other (not the crop circle thing )

Looks like I need to give them something calcium rich to nibble on, I think I'll try them on dark green leafy veg and see if they like it.

Thanks again,

Rob.