What do I feed my snails?

Question

So I've recently gotten into foraging and found a site called eattheinvaders.org that encourages people to eat invasive species. One of the most invasive species here in California is the common Garden Snail (Cornu aspersum). I've practiced identifying them so I don't accidentally mess with any native species and I've found a few hotspots from where to pick them.

After doing some research online I found out that you are supposed to purge the snails in case they've eaten anything like snail traps or pesticides. To do this, you basically keep them in a container for a couple days and feed them some clean food.

I want to do this in the most sustainable way so I am trying to use foods or food waste like egg shells or old vegetables. My question actually has a couple parts to it, but basically I want to know:

• What specific plants do snails eat in the wild?
• How much will what I feed them affect their nutritional value?
• Is there any foods that might cause them to produce toxins or diseases? I have some old celery that's going bad. Can I feed them that?
• What is the best food, sustainable food for me to feed them? Can I just go outside and pick up some leaves? Would a diet of old vegetables and egg shells be good enough?

I'm having trouble finding resources and studies on this aspect of heliculture.

Answer 1

We have kept a snail around for several years in a terrarium. I'll tell you that they will eat almost any plant material. They munched all the ferns down to dirt, so now I just toss a sprinkle of microgreen seeds in the terrarium every couple of weeks. They sprout, they grow and feed the snail, and then when it is looking sparse I sprinkle some more. The organic mix I got was under $15 for more seed than the snail could require in 5 years. I believe that the snail is doing alright because it lays eggs regularly.

Throw a few isopods into the terrarium and they'll process snail waste further to keep things clean.

I think this would suit your needs for the following reasons:

1. It is cheap, and you may already have microgreen seeds lying around.
2. It ensures that you're giving a variety of plant material for more comprehensive nutrition to the snail.
3. I think you'd have to go out of your way to feed them something that would cause them to develop concentrations of toxins - and it would likely kill the snail before you could eat it. BUT most plant alkaloids are present at highest concentrations in mature plants/leaves. By feeding the younger ones you reduce (eliminate?) the potential for the snails to accumulate such potential toxins.
4. I also throw in a bite of carrot, apple, broccoli stem, or anything else that would wind up in a compost pile - and the snail loves it all. BUT I limit the amount just because I don't want a compost pile on my kitchen counter and the sprouts do such a good job of feeding.