For many who love aquatic life or want an underwater pet, snails seem like an appealing choice due to their small size and interesting shells. But can snails actually live underwater?
If you’re short on time, here’s a quick answer: most land snails cannot survive for long periods underwater, but some aquatic snail species are fully adapted to underwater life.
In this comprehensive guide, we will cover everything you need to know about snails and their relationship with water, including:
The Difference Between Land Snails and Aquatic Snails
Land Snails
Land snails, as their name suggests, live primarily on land. There are over 35,000 species of land snails that inhabit a wide variety of terrestrial environments including forests, deserts, grasslands, and urban areas. Some key features of land snails include:
- They have a muscular foot that is adapted for crawling along the ground.
- They have a calcareous shell that protects their soft body. The shell can coil to the right or left depending on the species.
- They breathe using a lung-like structure called a pneumostome.
- Their diet consists primarily of plant matter including leaves, stems, flowers, bark, and fungi.
- During dry or cold periods, they can seal themselves off in their shell using a calcareous plate called an operculum.
- They require moisture to survive and are most active when conditions are damp.
- Some species hibernate during periods of drought or extreme cold.
Land snails play important ecological roles including breaking down organic matter and contributing to soil nutrient cycling. They also represent an important food source for many birds, mammals, insects, and other invertebrates.
Aquatic Snails
In contrast to land snails, aquatic snails spend most or all of their lives underwater. There are thousands of species adapted to various freshwater and marine habitats. Some key features of aquatic snails include:
- They have a muscular foot adapted for crawling on surfaces underwater.
- They have a streamlined shell or lack an external shell altogether.
- They have gills to breathe underwater.
- Their diet consists of algae, aquatic plants, detritus, and sometimes other small aquatic animals.
- Most species lay gelatinous masses of eggs underwater.
- Various adaptations allow them to float, sink, or cling to surfaces.
- Freshwater species require calm, oxygen-rich water to survive.
Aquatic snails are an integral part of underwater ecosystems. They graze on algae and detritus, recycling nutrients and organic matter. Their eggs and larvae represent an important food source for fish and other aquatic animals.
Some species can spread parasites and disease, or become invasive when introduced outside their native habitat.
| Land Snails | Aquatic Snails | |
|---|---|---|
| Habitat | Terrestrial environments like forests, deserts, grasslands | Freshwater and marine habitats |
| Breathing | Lung-like pneumostome | Gills |
| Diet | Plants, bark, fungi | Algae, aquatic plants, detritus, small animals |
| Eggs | Laid in clutches in soil or under debris | Gelatinous masses laid underwater |
| Adaptations | Operculum to seal shell, ability to hibernate | Floating, sinking, clinging adaptations |
Can Land Snails Live Underwater?
Land snails cannot survive for extended periods underwater, as they need access to air to breathe. Here’s an in-depth look at why land snails drown underwater and how long they can survive submerged.
Why Land Snails Cannot Survive Underwater
Land snails have lungs and breathe air directly from the atmosphere using a respiratory opening called a pneumostome. When submerged, the pneumostome closes to prevent water from entering the lung cavity.
While a snail can hold its breath for a while, it eventually needs to open its pneumostome to breathe. If still underwater, the snail will drown.
Additionally, land snails have permeable skin covered with mucus to prevent dehydration. When submerged, water passes through the skin into the snail’s body, diluting the internal fluids and disrupting the snail’s salt balance. This can quickly become fatal without access to dry land.
How Long Land Snails Can Stay Underwater
Most land snails can survive underwater for only a few hours at most before drowning. Exact time varies by species and individual snail.
- Garden snails – Up to 6 hours
- Giant African land snails – Up to 5 hours
- Vineyard snails – 4-5 hours
- Brown garden snails – 3-4 hours
Snails enter a state of inactivity and crawl into their shells to conserve energy when underwater, slowing their oxygen use. But eventually, they need to open their pneumostome to breathe. When deprived of air, most land snails will die within several hours.
Aquatic Snail Species That Live Underwater
Freshwater Aquatic Snails
There are over 500 freshwater snail species that spend their entire lives underwater. These include mystery snails, apple snails, ramshorn snails, and more. They live in ponds, lakes, rivers, and streams.
Freshwater aquatic snails have gills to breathe underwater. Their gills work like fish gills, extracting oxygen from the water. Species like Lymnaea stagnalis can even survive in low-oxygen environments.
Many freshwater snails are omnivores. They eat decomposing plants, algae films, and even dead animals. Some species like assassin snails are carnivores and eat other snails.
Fun fact: The giant African land snail can live underwater for up to 72 hours before needing air!
Saltwater Aquatic Snails
There are over 3,500 marine snail species. The most common groups are sea butterflies, sea slugs, limpets, and periwinkles. They inhabit intertidal zones, coral reefs, seagrass beds, and the deep sea floor worldwide.
Saltwater snails have gills or diffusion across their body surface to obtain oxygen at depth. However, intertidal species can also breathe air when exposed at low tides.
Many saltwater snails feed on algae, detritus, and biofilm coatings on surfaces underwater. Sea slugs are carnivores and eat sponges, soft corals, hydroids, or anemones.
The methane seep mussel, found 1.7 miles deep on the ocean floor, harbors chemosynthetic bacteria providing food for the mussel – and nearby snails like Rubyspira osteovora living in this extreme environment.
| Snail Habitat | # Species | Fun Fact |
|---|---|---|
| Freshwater | Over 500 | Can survive 72 hours underwater |
| Saltwater | Over 3,500 | Live 1.7 miles deep |
For more on aquatic snails, check out this freshwater snail guide and saltwater snail overview.
Caring for Aquatic Snails in an Aquarium
Water Conditions
Aquatic snails have specific water condition needs to thrive in an aquarium environment. The two most important factors are pH and hardness. Most aquatic snails do best in neutral to slightly alkaline water with a pH of around 7.0-8.0. Extremely acidic or basic water outside this range can be harmful.
Snails also need moderately hard water, between 5-12 dGH. Soft water lacks the calcium they need to build their shells. Other water parameters like temperature and filtration should match the needs of the fish species in the tank.
Perform regular partial water changes of 25-30% each week. This helps remove waste and replenish minerals in the water. Use a gravel vacuum to suck up debris from the substrate. Always treat new water with a dechlorinator to remove chlorine and chloramines.
An aquarium test kit allows you to monitor the pH, GH, ammonia, nitrite, and nitrate levels.
Food and Feeding
Most aquatic snails are omnivorous scavengers and will eat a variety of foods in the aquarium. Their main diet should consist of vegetables high in calcium like spinach, kale and zucchini. Introduce small slices or blanched pieces into the tank 1-2 times per week.
Snails will also feed on algae and biofilm growing on surfaces. Supplement their diet with calcium-fortified snail jello or wafers 2-3 times per week. Protein sources like shrimp pellets, fish flakes and spirulina can be given in smaller amounts.
Remove any uneaten food after a few hours to prevent decay.
The amount to feed depends on the type and number of snails in the tank. Overfeeding leads to wasted food and poor water quality. Observe their feeding habits and adjust amounts accordingly. The tank should not be too crowded either to ensure there are enough resources.
Most snails are nocturnal or crepuscular and more active at night and dusk/dawn.
Tank Mates
When selecting tank mates, avoid pairing snails with species that may prey on them like pufferfish and loaches. Slow moving snails can also be bothered by aggressive fish. Ideal companions include other peaceful community species like small tetras, rasboras, danios, corydoras catfish, dwarf gouramis, guppies, and mollies.
Certain shrimp and other invertebrates make good tank mates as well. Just be mindful of adding too many bottom-dwellers that may compete for food resources. Though nerite snails generally do not reproduce in freshwater, other common snails like mystery and rabbit snails can rapidly multiply and overrun a tank if both genders are present.
With the proper set up and care, aquatic snails can thrive in a community aquarium. Their active nature and interesting behaviors make them fun and unique additions. Following their specific needs for water parameters, diet, tank mates, and more allows both the snails and fish tank inhabitants to stay healthy.
Conclusion
While most land snails cannot live for extended periods underwater, certain aquatic snail species are well-adapted to underwater life in both freshwater and marine environments. By understanding the differences between land and aquatic snails and properly caring for true aquatic species, snail enthusiasts can successfully keep these interesting creatures in home aquariums.
