Hermit crabs hide within their shells or burrow under the substrate when afraid. They may also nip you with their large chelipeds when escape isn’t possible.
When first brought home, hermit crabs endure post-purchase stress (PPS). They may hide under the substrate for days or weeks, as a long journey and change of environment take a heavy toll.
Hermit crabs may fear handling because they don’t understand why you pick them up. Poor living conditions, excessive noise, and bullying from tankmates can cause fear in hermit crabs.
Hermit crabs can flourish in captivity with time and the right tank setup. For this to happen, you must understand what frightens hermit crabs and avoid those unwelcome situations.
Are Hermit Crabs Scared of Humans?
Wild hermit crabs have nothing to do with humans, spending their days buried under the substrate on a beach and avoiding the sun’s rays. As a result, they rarely keep the same hours as human visitors.
Hermit crabs have little reason to fear humans or trust us. Most hermit crabs will be cautious about interacting with an unfamiliar human. If nothing else, we’re considerably larger than them.
As you can imagine, handling hermit crabs magnifies this fear. They have no idea why we’re picking them up and likely assume we intend to kill or eat them.
It’s possible to gain the trust of hermit crabs in captivity, but it takes time to prove you’re not a threat.
Signs of Scared Hermit Crabs
The signs that hermit crabs are fearful include:
- Burrowing under the substrate.
- Hiding within the shell.
- Running for cover within the tank.
- Pinching with their chelipeds.
- Urinating on your hand during handling.
- Refusing to drink or eat.
If a hermit crab is terrified, it’ll shed its legs due to stress. Any lost legs will regrow when a hermit crab next molts. Shedding limbs is intended to distract and confuse the source of fear.
Why is My Hermit Crab Scared of Me?
As an owner, you’re responsible for making hermit crabs comfortable by learning the most common fear triggers and removing them wherever possible.
Here are the most common causes of fear in hermit crabs:
1/ Post-Purchase Stress (PPS)
All captive hermit crabs go through post-purchase stress.
Try to see things from a hermit crab’s perspective. It has been removed from the beach and into captivity, often via a beachfront gift store with difficult living conditions.
PPS is distressing to watch. A hermit crab will burrow itself, potentially shedding limbs.
Give a new hermit crab space, and it may overcome PPS. The closer a habitat mirrors a wild environment, the sooner it’ll overcome its fear and interact in its new home.
Unfortunately, some hermit crabs die during PPS. This is called Post Purchase Death Syndrome (PPDS).
2/ Unnecessary Handling
It’s impossible to avoid handling hermit crabs indefinitely. Sometimes, you’ll need to pick up a hermit crab. For example, moving a hermit crab to another tank to permit deep cleaning.
To safely handle hermit crabs, follow these steps:
- Stretch the palm of your hand, leaving no loose skin to pinch.
- Gently grip the shell with the other hand.
- Guide the hermit crab onto your flat palm.
- Lift the hermit crab, still holding onto the shell., but don’t dangle it midair.
- Put the hermit crab down when it’s safe.
The Journal of Chemical Ecology explains how handling can help you bond with your hermit crabs, as they’ll recognize your scent. Once you’ve earned the trust of hermit crabs, they’ll tolerate handling.
3/ Household Pets
Other household pets can cause stress to hermit crabs.
For example, cats and dogs may circle a hermit crab tank due to curiosity. The hermit crabs will assume these animals are predatory, burrowing or hiding to remain safe.
Avian pets are no better. Birds swoop from the sky and take hermit crabs from the beachfront. Captive hermit crabs will instinctively fear pet birds, even if there have been no prior encounters.
4/ Inappropriate Environment
Hermit crabs become stressed if their environment is unsuitable for their needs.
- Don’t expect a hermit crab to flourish alone, as they’re social animals that live in large colonies.
- Provide an ambient temperature of 80°F.
- Ensure a humidity level of 80% by using a hygrometer.
- Provide at least 6 inches of substrate for burrowing.
- Offer spare shells for hermit crabs to trade.
- Provide entertainment, like climbing apparatus.
Food diversity is important to hermit crabs. The Journal of Experimental Marine Biology and Ecology explains that wild hermit crabs rarely eat the same food twice in 24 hours.
5/ Excessive Stimulation
Choosing where to position a hermit crab tank is a vital care component.
Are hermit crabs scared of noise? We can’t be sure how good a hermit crab’s hearing is, especially when buried, but it’s not among their strongest senses.
According to the journal Applied Animal Behavior Science, noise can confuse and disorient hermit crabs.
Are hermit crabs scared of the dark? In many respects, the reverse is true. Hermit crabs prefer dim lighting, so keep a tank dark at night and avoid placing it too close to intense light.
Hermit crabs get along and live harmoniously in large colonies in the wild. This is one of the elements that should be replicated in captivity, as hermit crabs are much happier with others.
Sometimes, a hermit crab’s fear has nothing to do with you but with another colony member.
Hermit crabs may look like they’re fighting when they’re playing. They may engage in ‘feeler fights’ for fun or attempt to impress a potential mate. Sometimes, these conflicts turn aggressive.
Reasons for hermit crabs to fight include:
- Jealousy over shells – One hermit crab may try to eject another to steal its shell.
- Territoriality – Some hermit crabs dislike sharing resources or space.
- Alpha status – Hermit crabs may fight to establish a pecking order within a colony.
- Mating rights – A female will have a choice of mates, and males compete for her attention.
As explained by Ethology, most hermit crabs remember their relationships with conspecifics in the wild. If one hermit crab bullies another, it’ll be stressed during its time in the tank.
If this happens, the aggressive hermit crab should be moved to another tank.
7/ Nervous Nature
Some hermit crabs are more nervous than others. If you have a large colony of hermit crabs in a tank, check how they interact. One or more hermit crabs may prefer space and privacy.
If the nervous hermit crab isn’t being bullied and is eating and drinking, there’s no need to worry. Let the hermit crab do as it pleases, as you can’t force it to become more outgoing.
How Do I Make My Hermit Crab Not Scared of Me?
Once the hermit crabs overcome PPS and have gained enough confidence to venture outside their shells and substrate, maintain trust by following these guidelines:
- Provide an environment that mirrors their natural habitat.
- Avoid handling unless necessary.
- Provide a varied diet, occasionally by hand.
- Add new shells and hiding places to the tank.
- Provide opportunities to play and exercise.
Although popular pets, hermit crabs were never bred for captivity. Thankfully, with the right care and support, hermit crabs can overcome their initial fear of humans and flourish in their new lives.