Some hermit crabs can live long, decades-spanning lives. The oldest known captive hermit crab lived to the age of 44. It’s not uncommon for wild hermit crabs to live at least 30 years. However, they endure a reputation as delicate animals that rarely live longer than a few months.
Wild hermit crabs outlive pet hermit crabs, and land hermit crabs tend to live longer than marine hermit crabs. Fewer predators are found on the beach, and the sand is less littered with debris than the ocean.
Land hermit crabs also have the potential to live longer in an aquarium as pets, although they’re exposed to more risks. It’s easier to replicate the precise temperature and humidity levels of a terrestrial hermit crab than to maintain perfect water conditions for a marine hermit crab.
With the proper care, captive hermit crabs can live long lives, but appropriate care is a significant caveat. Hermit crabs can fall victim to an unsuitable environment, toxicity, bacterial infections, and intense stress, and this is why so many pet hermit crabs die within a year.
Take care of a captive hermit crab well, and you can expect to enjoy 10+ years of companionship.
How Many Years Can a Hermit Crab Live?
Hermit crabs that live a cautious life in the wild are more likely to survive, which is one of the reasons why they live in colonies. There’s safety in numbers, and hermit crabs dwell in groups of up to 100.
Naturally, different species of hermit crab will also have different lifespans. Let’s review the average lifespan of hermit crabs in the wild and captivity:
Average Age of Marine Hermit Crabs
| Hermit Crab | Average Wild Lifespan | Average Captive Lifespan |
| Dwarf Blue Leg Hermit Crab | Up to 30 years | 1 to 2 years |
| Electric Orange Hermit Crab | Up to 30 years | Up to 20 years |
| Halloween Hermit Crab | Up to 30 years | 8 to 10 years |
| Polka Dot Hermit Crab | Up to 30 years | 3 to 5 years |
| Scarlet Reef Hermit Crab | Up to 30 years | 4 years |
Average Age of Land Hermit Crabs
| Hermit Crab | Average Wild Lifespan | Average Captive Lifespan |
| Caribbean Hermit Crab (aka Purple Pincher) | Up to 30 years | Up to 20 years |
| Cavipe | Up to 30 years | From 3 to 12 years |
| Ecuadorian Hermit Crab | Up to 30 years | From 10 to 30 years |
| Ruggie | Up to 30 years | Around 10 years |
| Strawberry Hermit Crab | Up to 30 years | 25 to 30 years |
Naturally, if you’re considering adopting hermit crabs, these average lifespans may factor into your choice. Just remember that captive hermit crabs will only live as long as their quality of care allows.
Why Do Wild Hermit Crabs Live Longer?
Life within an aquarium or tank in a home with food and water should be much safer than in the natural world, where potential predators lurk everywhere.
Unfortunately, it can be challenging to mirror a hermit crab’s wild environment.
Temperature, humidity, and substrate must all be carefully monitored within an aquarium, as the slightest deficiency can have significant consequences. Human residences can also contain toxins that a hermit crab will not encounter in the wild.
Wild hermit crabs are also more relaxed and comfortable, despite the dangers that nature throws at them. Hermit crabs are social animals who are happier when surrounded by conspecifics in familiar terrain.
What’s The Oldest Hermit Crab on Record?
The oldest hermit crab in the world lived to the impressive age of 44 before dying in 2021. The hermit crab, named Jonathan Livingstone, lived in the Shell Point Retirement Community in Fort Myers, FL.
Jonathan Livingston was purchased from a seafront gift store in Delaware in 1976 and flourished in captivity. His long life was due to excellent care, with owner Carol Ann Ormes becoming a celebrity in the world of hermit crab ownership due to her intuitive understanding of what these animals need to flourish.
Jonathan Livingstone enjoyed the company of a conspecific named Crab Kate for 35 years, so his long life wasn’t by chance. Carol Ann Ormes’s efforts show that hermit crabs can live for decades in captivity.
How Long Do Hermit Crabs Live in the Wild?
Hermit crabs can live around 30 years in the wild if they avoid the many and varied pitfalls found in nature. Some can live longer, like Jonathan Livingston (mentioned above).
As a rule, the bigger a hermit crab is, the longer it’s likely to survive in the wild. A study in PLoS One found that hermit crabs with a larger body mass were more likely to survive into adulthood.
Besides old age and nature taking its course, what kills wild hermit crabs? There are four primary causes of hermit crab death in the wild:
Predators
Marine hermit crabs, in particular, are constantly exposed to danger. Many species of fish feast on hermit crabs, as well as octopi.
As explained by Symbiosis: Evolution, Biology and Ecological Effects, marine hermit crabs defend themselves by forming symbiotic relationships with sea anemones. The hermit crabs offer a protective shell, while the anemones are toxic and deter predators.
On land, it’s easier for terrestrial hermit crabs to avoid predators. While land hermit crabs need to soak in seawater occasionally, they can stay in shallow enough water to avoid predatory fish.
This doesn’t mean the beach is devoid of risk for hermit crabs. True crabs are larger and occasionally feast on hermit crabs, while birds eat hermit crabs.
Most hermit crabs remain burrowed under the sand to avoid this outcome unless actively foraging for food or bathing. If they detect a threat, hermit crabs usually hide within their shell, though on a rare occasion, a hermit crab may fight back with its large cheliped.
Loss of Shell
All hermit crabs need a shell, whether wild or captive, marine or terrestrial.
Wild hermit crabs that lose their shells are extremely unlikely to survive. Without a shell, a marine hermit crab is easy pickings for even the smallest fish.
The need to crunch through a shell may be enough to deter some predators. With no protection, this will not be a concern. Equally, without a shell, a hermit crab has nothing to offer a sea anemone in exchange for protection.
On land, hermit crabs are equally exposed to predators without a shell. If confronted by a true crab, most hermit crabs would hide within a shell until the danger passes. It’s a rare hermit crab that could overpower a true crab in a fight.
Also, losing a shell leaves a hermit crab exposed to the elements. As hermit crabs are native to hot countries, a lack of protection from the sun can leave a hermit crab dead within hours.
Insufficient or Excessive Water
Issues with water for wild hermit crabs largely revolve around land dwellers. After all, marine hermit crabs spend their lives underwater – often at the ocean’s deepest depths, and they’ll not struggle to find water.
Land hermit crabs need to bathe in salt water at least once daily. Hermit crabs will typically wait for the tide to come in, but if they can’t access water for any reason – perhaps due to predatory birds blocking access – they can find themselves in trouble.
Equally, land hermit crabs can’t breathe underwater, so they must judge their access to the ocean carefully. If a terrestrial hermit crab wanders too far into the sea and finds itself completely submerged in water for a prolonged period, it may drown.
Plastic Pollution
It’s no secret that our oceans are in crisis due to plastic waste, with every square mile of the world’s oceans now containing around 46,000 pieces of plastic.
According to the Marine Pollution Bulletin, hermit crabs are instinctively attracted to the scent of plastic, mistaking this for a food source. This, naturally, means that hermit crabs will approach the plastic, which could be in the sea or washed up onto the shore.
Hermit crabs can mistake plastic for a shell, getting trapped within. The Journal of Hazardous Materials explains that hundreds of thousands of hermit crabs die yearly due to plastic pollution.
How Long Do Hermit Crabs Live in Captivity?
Hermit crab life expectancy in captivity varies wildly, depending on your care regime.
If you’re cautious and avoid all potential pitfalls to a hermit crab’s life, it should live around 15 years, possibly longer. Once again, a reminder that Jonathan Livingston was captive, and he lived to 44.
Unfortunately, this is often the exception rather than the rule. Many people lose their hermit crabs in a much shorter time, especially novice owners. Hermit crabs have a reputation as delicate, short-lived pets. Why do hermit crabs die in captivity so quickly?
Hermit crabs can fall foul to many problems and concerns that end their lives. Thankfully, most can be avoided by understanding how to care for your pets. Whether adopting marine or land hermit crabs, here are the eight most common causes of death:
Stress
Stress and trauma are arguably the biggest killers of captive hermit crabs. It’s quite a shock for a hermit crab to be plucked from its colony on a beach and expected to start a new life in captivity.
Some hermit crabs die almost immediately upon setting up a habitat. The stress of being kept in a gift shop, often in wholly inappropriate conditions, then undergoing a journey into a new home is just too much for them. This is known as post-purchase stress (PPS).
Be patient if you bring home a hermit crab from a beach holiday. It’ll likely burrow underground and hide for at least a few days, possibly longer. Give the hermit crab time, space, and, if possible, companionship from a conspecific to ease the transition.
Inappropriate Environment
Even if hermit crabs can overcome the stress of beginning life as a pet, too many people don’t understand the complex needs of these animals.
An aquarium/tank should be set up ahead of time, with the following criteria met:
- An aquarium no smaller than 10 gallons – larger if you’re keeping multiple hermit crabs.
- No less than 4-6 inches of appropriate substrate.
- Humidity of 80% for land hermit crabs to prevent suffocation.
- Temperature of around 80OF for land hermit crabs, and a water temperature between 72–78OF for marine hermit crabs.
- Plenty of climbing apparatus and hiding places for recreation.
- Company, as hermit crabs live in large colonies in the wild.
Hermit crabs are often presented to children as starter pets but can have complex needs. Anybody looking to take on hermit crabs must understand how to provide them with an appropriate lifestyle.
Poor Diet
As omnivorous scavengers, they’ll eat more or less anything they can find. Hermit crabs also like variety in their diet, rarely eating the same thing twice in 24 hours.
The same will apply to captive hermit crabs. If you try to feed the same foods repeatedly, no matter how delicious, your pets will lose interest and stop eating. This will have health repercussions, most notably a vitamin and mineral deficiency that impacts the exoskeleton.
Quality in hermit crab food matters just as much as quantity. You’ll need to ensure your hermit crabs receive everything they need in their diet, most notably Vitamins A and E, protein, and calcium. These ingredients bolster the strength of a hermit crab’s exoskeleton.
If you have concerns about a hermit crab’s nutrition, especially critical calcium, add cuttlebone to a habitat. This will tempt your hermit crabs to tuck in and gain all the health benefits they need.
Unsuitable Water
Never offer captive hermit crabs water straight from the tap. Land hermit crabs need water to drink and bathe in, but this can’t contain chlorine, copper, or other heavy metals.
The best way to manage a hermit crab’s water needs is to use bottled water, which is a little safer than a water purifier in the home. You’ll also need to add ocean water to this from a pet store – not table salt.
Naturally, water is also critical for marine hermit crabs. You’ll need to find the perfect saline level for the hermit crab species in your aquarium. You’ll also need to keep the water clean and at an appropriate temperature.
One of the reasons marine hermit crabs tend to have shorter lifespans as pets is the difficulty in matching natural water conditions. As per the ICES Journal of Marine Science, variations in pH levels can have dire consequences for hermit crabs.
Bacterial Infection
Hermit crabs flourish in a clean environment, so you’ll need to ensure you conduct regular spot cleaning. At least once every 2-3 days, skim the top of the substrate and remove any feces. If you spot any uneaten and spoiled food, clear that out.
If you allow food to rot and waste to linger, you may attract bacteria or fungi in a hermit crab tank. This can lead to fatal – and contagious – illness. If one of your hermit crabs is acting out of sorts, isolate it at once and deep clean the entire habitat.
Deep cleaning of every aquarium/tank surface should be done around once a month – more often if you have many hermit crabs. This will prevent bacteria from gaining a foothold.
Keeping on top of bacteria is even more critical if you have marine hermit crabs. Bacteria can break down chitin, the protein in a hermit crab’s exoskeleton, and lead to shell rot. This will eventually poke larger holes in the exoskeleton, inviting further issues.
Toxicity
Toxicity is a major concern for captive land hermit crabs and can come from various sources. We have explained the dangers of heavy metals in water, but you’ll also need to protect hermit crabs from fumes.
That means avoiding spray cans around your hermit crabs. Don’t use air fresheners, bug spray, antiperspirants, or anything else that could cause damage to a hermit crab’s gills.
Another major concern is paint. Some people look to paint pretty decorations on a shell to add more aesthetic appeal to a hermit crab, but this will invariably be fatal.
Impact Injury
Hermit crabs love to climb, so provide them with climbing toys. Don’t be surprised if hermit crabs still climb the walls of a tank. They may even hang upside down from the ceiling.
This is natural play and recreation for hermit crabs, so there’s nothing to worry about. Just be mindful of the potential for impact injuries following any falls. Hermit crab exoskeletons are tough but not invulnerable.
Ensure a habitat has 4-6 inches of substrate to provide a soft landing if a hermit crab falls from height. If you keep more than one hermit crab, add more substrate. A hermit crab may be sleeping or molting under the sand, so more padding is needed.
Killed by a Fish or Another Hermit Crab
Hermit crabs harmoniously share space in the wild. All animals can fight, and hermit crabs are no exception. According to Behavioral Ecology and Sociobiology, conflict can grow intense.
Most hermit crab fights arise over territory, shells, or mating rights. Reduce the risk of hermit crabs growing hostile by getting a large tank of 20 gallons or more, so every occupant has enough space to retreat and be alone when necessary.
You may be unable to stop hermit crabs from fighting over shells, but providing a selection of spare shells may reduce the temptation to challenge others. Offer a selection of shells in various shapes and sizes.
If you’re keeping marine hermit crabs with fish in an aquarium, they’ll eat algae and keep the tank clean.
How to Make Your Hermit Crab Live Longer
Follow these care steps to give your hermit crab the best chance of a long, active life:
- Offer plenty of living space, deep substrate, and an ideal temperature and humidity.
- Provide company for hermit crabs, but ensure unnecessary conflict is avoided.
- Prevent stress by avoiding excess handling and providing enrichment.
- Feed your hermit crabs a varied and nutritionally balanced diet.
- Never use chlorinated water.
- Clean a hermit crab’s enclosure regularly.
- Avoid anything toxic, including painted shells and citrus tree branches.
While a hermit crab could die unexpectedly, introducing the above measures will lead to a better quality of life and keep pet hermit crabs alive for longer.
