Shell discolouration (garden snail)

[prelude]

I care for a garden snail, who has lived with us for two years. The snail lives indoors, inside a terrarium. I provide calcium through cuttlebone, and a diet of greens including kale, cos lettuce and spinach. 

In the past couple of months, I have noticed that the snail's shell is becoming discoloured. Could anyone help identify what could be the cause of this?

Thank you in advance!

Image of discoloured shell: ibb.co/5R0LjW8

[littlegoldsnail]

Does he get any protein? Do you keep him with any other snails?

I would first try offering it some sort of a protein source (bloodworms, krill or a meat based fish food is good). Also try feeding some more variety, snails need variety to thrive.

Some good foods may include:

Sweet potatoes
Blueberries
Squash and pumpkin
boiled carrots
Banana

Most fruits and veggies are fine, just avoid citrus and anything in the onion family.

[prelude]

Thanks for your feedback!

The snail has not received any protein - I wasn't aware that this was needed and he has been with us for just over two years! Although, there are small earth worms that are in the soil in his terrarium, would he have been feeding from these? What could be purchased from a supermarket that would be appropriate? Also, how often would I need to feed this?

The snail is housed alone, as I am not wanting to breed snails. This snail (affectionately referred to in our household as Snailey), came into our care as we found him in a carpark with a partially cracked shell - I imagine a bird possibly dropped the snail. The snail's shell recovered well over about 6 months, and by that time, we decided to keep our little friend.

The shell discolouration is fairly recent, progressing over the past 6-8 weeks.

Apart from protein deficiency, could problems arise from limited sunlight (living indoors), or from consumption of too much calcium?

Thanks again!

[littlegoldsnail]

I doubt he would feed on live earth worms. You can find freeze dried bloodworms or meat based fish food at any pet store or in the pet section at Walmart. I’m not sure what stores are available to you where you live.

There is a small amount of protein in spinach, but it’s not very bio available for snails so they won’t really get any of it.

I’m not aware of snails needing UVB (sun light) to thrive, I think they do fine indoors.

I think feeding protein about once a week or so should be fine. They don’t need a lot of it, but it is a necessary part of their diet.

[morningcoffee]

This is the outer layer of the shell, the periostracum ( en.wikipedia.org/wiki/Periostracum ) wearing away which is common in older snails.

I agree with littlegoldsnail that a more varied diet, including a protein source, would be good for your snail however it won't restore the look of the shell.
There is a good post from Liguus about this here: petsnails.proboards.com/post/138056/thread

[Liguus]

Yeah, since this is on the older part of the shell it's a natural wearing away of the periostracum layer. Happens to older snails. There is nothing you can do to repair it, however you can possibly prevent it from getting any worse. In a lot of cases I suspect the substrates used can turn acidic and if they are neutralized with something like limestone flour or crushed oyster shell it will be less likely to wear away at the shell.

[prelude]

Jan 10, 2020 20:01:09 GMT Liguus said:

Yeah, since this is on the older part of the shell it's a natural wearing away of the periostracum layer. Happens to older snails. There is nothing you can do to repair it, however you can possibly prevent it from getting any worse. In a lot of cases I suspect the substrates used can turn acidic and if they are neutralized with something like limestone flour or crushed oyster shell it will be less likely to wear away at the shell.

That is really interesting! Would I blend the limestone flour through the soil or sprinkle on top? I am not sure on acidity levels inside the garden terrarium, but you have inspired me to find out! What is the ideal pH level of a garden terrarium for a snail?

[Liguus]

I would just mix it in. The limestone flour will work faster, but I have also used crushed oyster shells in my substrate mix.

The pH doesn't have to be anything crazy, just neutral or slightly above neutral. I would aim for a 7 or 8.

[GailTheSnail]

WOW 2 years is a really long time, you’re doing something right! As others have said, these kinds of things happen as they age but making sure they have calcium like cuttle bone will help

[daniele]

Jan 15, 2020 23:37:01 GMT Liguus said:

I would just mix it in. The limestone flour will wolf faster, but I have also used crushed oyster shells in my substrate mix.

The pH doesn't have to be anything crazy, just neutral or slightly above neutral. I would aim for a 7 or 8.

are there any other possible reasons apart from the acid soil in your opinion? this guy is one year and a half, and a part of her shell got white, but another part seems to be in a lighter shade, like if a part of it was  "peeled" .. As calcium source i only use cuttlefish bone and egg shells, but I will try to buy limestone flour too asap!
in the pic you can see the three different shades, in the lower part of the shell

[Liguus]

given the area, I would say it is the substrate (dragging shell bottom across the soil), however yes, there are other reasons a shell could fade. With old age sometimes it is just inevitable as the protein layer gets worm down from things like fluctuating between being wet and dry.