Last Updated on: 4th October 2023, 02:15 pm
All hermit crabs are born in the ocean, hatched from eggs released upon contact with saltwater. Most remain in the sea, while some make their way to land.
Marine hermit crabs must remain underwater. They occasionally head to the shore to find food, but only for a while. Too much time out of the water closes their gills, leading to suffocation.
Terrestrial hermit crabs can breathe on land as long as they remain in humid conditions and keep their gills moist, but they can’t breathe underwater for more than 20 to 30 minutes.
A land hermit crab will drown if left in the water and can’t escape before its oxygen is depleted.
Do Hermit Crabs Live in Water or on Land?
Hermit crabs live on land and underwater, but never both. Most hermit crabs are aquatic animals that need to live in water to breathe, while many pet species of hermit crabs are terrestrial.
Aside from occasional interactions on the shore of a beach, they never interact in the wild.
Land-based hermit crabs head into the sea to birth their young, mate, or bathe. Marine hermit crabs, meanwhile, occasionally visit dry land to seek food.
In captivity, aquatic hermit crabs must spend their time in an aquarium, while their land-based counterparts can’t be submerged in a large body of water.
How Long Can Hermit Crabs Stay Underwater?
Aquatic hermit crabs can spend their entire lives underwater. If food is plentiful beneath the surface, a marine hermit crab needn’t venture onto dry land.
For terrestrial hermit crabs, this is a different story. Land-based hermit crabs need humidity and drinking water to keep their gills moist but rely on carbon dioxide to breathe.
While terrestrial hermit crabs occasionally immerse themselves in water, they hold their breath. No hermit crab can hold its breath indefinitely, so it’ll drown if it can’t escape the water.
Most healthy adult hermit crabs can hold their breath for 20 to 30 minutes. Wild terrestrial hermit crabs will visit the ocean briefly before returning to land.
Captive hermit crabs will submerge in water and occasionally emerge to breathe.
How Long Can Hermit Crabs Live Out of Water?
Marine hermit crabs can only survive on dry land for a while. If out of water for too long, marine hermit crabs are at significant risk of suffocation.
Aquatic hermit crabs breathe in oxygen found in the water.
This is drawn to the gills by the scaphognathite, an appendage below the mouth. Once oxygen is processed by the gills, it’s passed through the blood, and CO2 is expelled through the mouth.
A marine hermit crab that has spent too much time on dry land will start blowing brown bubbles. This is a sign of stress, suggesting the hermit crab needs water.
How To Tell Land And Marine Hermit Crabs Apart
Visually, there’s little difference between marine and terrestrial hermit crabs. Both have 10 legs, and neither is born with a shell. They get their shells from other animals, like mollusks.
Marine hermit crabs are likelier to have decorative features on their legs, like stripes or spots. Most terrestrial hermit crabs are one color.
Aquatic hermit crabs may also have a sea anemone attached to their shell.
As discussed by Helgoland Marine Research, they enjoy a symbiotic relationship. Anemones protect hermit crabs from predators, while the hermit crabs will share food.
One way to tell marine and terrestrial hermit crabs apart is where you find them. Aquatic hermit crabs never venture far from the shore and are unlikely to be found on the beach when the tide is low.
Where Do Wild Hermit Crabs Live?
Hermit crabs are found on beaches. The most significant populations of wild hermit crabs are located in the western Atlantic territories, the Caribbean, Africa, Australia, and the Indo-Pacific region.
Some terrestrial hermit crabs can be found in the U.S., particularly in territories with beaches that border the Atlantic. The Florida Keys is home to various hermit crabs.
Do Hermit Crabs Live in the Ocean?
Most hermit crabs live near the ocean floor in the deepest part of the sea, although some will hide in coral reefs in shallower waters. There are many predators, including countless fish species.
Terrestrial hermit crabs enter the ocean but can’t live underwater.
All hermit crabs are born in the sea. They hatch as larvae known as zoeae, with those that survive long enough evolving and moving to dry land after 2 months.
Can Hermit Crabs Live in Freshwater?
Only one hermit crab species, Clibanarius fonticola, lives in freshwater.
This hermit crab is found in Espiritu Santo, the largest island in the Republic of Vanuatu. According to the Journal of Crustacean Biology, the Clibanarius fonticola was discovered in 1990.
If you wish to see one, they live in pools of water in the village of Matevulu.
Shell selection is quite limited for Clibanarius fonticola, so they’ll use shells previously occupied by Clithon corona, a freshwater snail observed throughout the Asia-Pacific region.
Do Marine or Land Hermit Crabs Make Better Pets?
Marine hermit crabs can keep a tank clean by eating naturally occurring algae if you keep fish compatible with hermit crabs. However, they aren’t quite as interactive as terrestrial hermit crabs.
While handling should always be limited for hermit crabs, those who live on land can spend a short amount of time outside their habitat. Marine hermit crabs must stay underwater at all times.
Aquatic marine hermit crabs are higher maintenance, as you’ll need to heat and change the water in an aquarium regularly. They can be highly decorative, as many marine hermit crabs boast striking colors.
Avoid taking on just one if you adopt marine or terrestrial hermit crabs. They’re social animals that grow bored when forced to live alone. Ideally, you need a minimum of 4-5 hermit crabs.
Caring for Marine Hermit Crabs
Marine hermit crabs must live in saltwater. If you pair them with fish, keep this in mind. Popular freshwater fish, like the betta, aren’t good tankmates for hermit crabs.
The water must meet these criteria to create an aquarium suitable for hermit crabs:
| Water Temperature | 72°F – 78°F |
| Water pH | 8.0 – 8.4 |
| Water KH | 150 – 215 |
| Water Hardness | 8 – 16 dH |
| Water Gravity | 1.021 – 1.028 |
Also, aquatic hermit crabs can’t be kept out of the water for long. You’ll need a second tank to host them while cleaning and replacing the water.
Caring for Land Hermit Crabs
Terrestrial hermit crabs have an erroneous reputation as easy pets to care for. While they need less intense attention than a cat or dog, hermit crabs still need a high standard of care.
You’ll need the following before introducing terrestrial hermit crabs to your home:
- The tank must be heated to around 80°F and have 80% humidity.
- A tank of at least 10 gallons, bigger if you take on more than 5 hermit crabs.
- No less than 6 inches of substrate for the hermit crabs to burrow, hide, and sleep under.
- Entertainment within the tank, like climbing apparatus.
While hermit crabs have gills, they don’t all live on land. Most hermit crab species are aquatic and should never leave the water. If you have land-based hermit crabs, they should be housed in a tank.
