You might not find many people here who are familiar with the univalves of the Maldives. Your snails look like those in the US that have a predatory role, often feeding on other snails, but that would just be a guess on my part.

I suspect rhizo is thinking about decollate snails. But not so. The shells of decollate snails appear to be broken because the tip is missing.

And, as far as I'm aware, decollates are only legal in the 7 southern-most counties of California.

See images & info at the link, below...

When it comes to identifying your snail and its habits, I suggest you contact your county Extension Service office. This interactive map will help you locate that office ---
http://www.csrees.usda.gov/Extension/

EDIT:
Oops!
For some reason I thought you were in Texas. (sigh).
To identify the snail, you'll need to contact an agricultural authority where you live.

Here is a link that might be useful: decollate snail

This post was edited by jean001a on Sun, Nov 9, 14 at 16:22

Jean, that's not the snail I was thinking of, but I have very little information about terrestrial snails unless they are of the usual garden variety.

I hope that our OP takes the initiative to search out the ID of these snails....I'm curious.