Range: Cosmopolitan Habitat: Intertidal areas, rocks, under sand, mudflats, and among underwater vegetation Size: Up to 2.5 inches (6cm) long Diet: Snails, bivalves, worms, and algae Threats: Nudibranchs Life span: Unknown

Transcript:

Today on Animal Fact Files we’re discussing bubble snails. Pop over that subscribe button, and thank you to moist for today’s request. There are two types of animals commonly referred to as bubble snails. The kind of bubble snails we are talking about today have thin shells that are almost spherical in shape; the kind of bubble snails we are not talking about today are the snails that make bubbles and use them as a floating raft. We’ll have to cover them in another episode.

Bubble snails are also known as bubble shells and paper bubble shells because their shells tend to be quite thin; so thin, they often appear transparent. Bubble snail shells don’t always do the best job of protection either. Some bubble snails are too big to fit into their teeny shells, and in others the shell may be receding into body, making it almost an internal structure. Bubble snails are also sometimes called “head shields” because they share an order with slugs commonly referred to as head shield slugs. I’m sure you can see why.

A lot of bubble snail classification comes from samplings of shells without a body. This, obviously, doesn’t provide the whole picture, so their classification is changing as scientists use more precise methods of identifying species. Heck, new species of bubble snails are still being discovered, so there’s still a lot to learn!

Bubble snails are found throughout most of the world’s oceans, even polar areas! Some species live in intertidal areas among rocks and under the sand as well as mudflats. Sometimes they can even get exposed to air! Other species can be found at greater depths, usually in places with vegetation. Specifically speaking, bubble snails really like eelgrass, and they’re mostly active during the night. During the day, they make mucus tunnels under the sand that collapse as they move through them. The bubble snails will actually trail mucus below their foot as well as over their head in order to allow this kind of movement.

Bubble snails are small. Though the largest bubble snails reach more than two and a half inches (6cm) in length, most species are less than an inch long with the shell sometimes only reaching half their body length. This implies that they don’t make much of a meal. Not that they taste very good anyway; some species of bubble snails are thought to be toxic - though this doesn’t stop nudibranchs from eating them. Bubble snails may, however, be able to let out a chemical signal to others in the area that they’re under attack, which is great for breeding season when they gather in large groups.

Bubble snails possess both male and female reproductive organs, but they still have to breed with another individual in order to produce offspring. They’ll line up with each end to their partner’s opposite because their reproductive organs are on opposite ends. Both individuals from a mating pair are able to lay eggs as long as both receive sperm. If they don’t, it’s not a big problem because bubble snails mate with multiple partners. Bubble snail eggs are laid in stringy, noodle-like clusters that contain upwards of 200,000 eggs. One snail may produce five or more of these clusters. The eggs are usually laid in vegetation such as eelgrass and the larvae look like teensy floating snails with wings which are eventually shed and replaced with the adult snail’s squishy body.

Some bubble snails are predators and eat other snails, bivalves, and worms such as bobbit worms, but others are herbivores and eat algae. How long they can live is a secret they’re currently keeping to themselves.

For more facts on bubble snails, check out the links in the description. Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files.