All You Need To Know About Red Hermit Crab

red hermit crab
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Red Hermit Crab Introduction

The red-clawed hermit crabs are a group of small, terrestrial isopods that live in the intertidal zone. They have been found on all continents except Antarctica and Australia. The species vary greatly in size from less than 1 cm to over 10 cm long. Most species can be distinguished by their coloration: they range from dark brown or black with white spots to bright orange with yellowish stripes. Some species also have distinctive markings such as large eyespots or even spines along their backs. Red-clawed hermits are omnivorous scavengers; however, some species will eat other invertebrates including insects, worms, snails, slugs, mollusks, sea anemones, jellyfish, and fish eggs. In addition, many species feed on algae and detritus.


There are three main characteristics used to identify a red hermit crab: size, coloration, and shape of the carapace. Size refers to how big the animal is compared to other animals of similar age. Coloration includes patterns on the body and legs, and whether the eyes are orange or black. Shape describes the general appearance of the shell. A hermit crab’s carapace looks more rounded than an oyster’s flat one.


A red hermit crab grows larger over time. At birth, the average length of a hermit crab is between. After six months, the average adult hermit crab measures around, although individuals can grow much bigger. Adult males usually reach lengths greater than females.

red hermit crab
A red hermit crab – Photo by Neil Turner

Red-clawed hermit crayfishes grow up to about 2 inches long. Their shells are usually between 3/4 inch and 11/16 inch. There are two types of hermit crabs: those who have a hard outer covering called a “carapace” and those without this cover. Those with a carapace tend to be larger because it protects them against predators. Hermit crabs without a carapace may not survive for very long if attacked by a predator.


Hermit crabs come in different colors depending on what part of the world they’re from. For example, there are four basic colors in North America: blue, green, pink, and purple. These colors correspond to the following regions:

Blue – Pacific Northwest

Green – California coast

Pink – Gulf Coast

Purple – Atlantic Ocean

In Europe, most hermit crabs are light gray or tan colored. However, there are exceptions like the European common hermit crab which has reddish-orange claws. Other examples include the Mediterranean hermit crab, which comes in various shades of grey, and the Japanese hermit crab, which ranges from pale cream to deep maroon.

Most hermit crabs have dark brownish-colored exteriors. Some species have white spots on their backs, whereas others do not. There are four basic colors: yellow, green, blue, and purple. Yellow hermits are often referred to as snowmen due to their resemblance to the cartoon character. Green hermits are sometimes called sea turtles because of their large size and round carapaces. Blue hermits are commonly called clownfish because of their bright coloring. Purple hermits are typically smaller than the rest of the hermit crabs and tend to be darker in color.

Hermit crabs come in different colors depending upon what type of food source they prefer. For example, blue crabs like to eat shrimp while green crabs like to eat seaweed. If you see a hermit crab eating something else besides its usual diet, then chances are it has just moved into a new area where there is no suitable food available yet. This could mean that the hermit crab was recently released from captivity or that it is looking for a mate.


Shell shapes vary among different types of hermit crabs. Most hermit crabs have a broad oval-shaped carapace. However, there are two exceptions: the first exception has a very narrow carapace and the second type has a triangular-shaped carapace. These two types of shells are known as “snowman” and “diamondback”, respectively. Snowmans’ bodies are covered in tiny bumps while diamondbacks lack any bumps at all. Both types of hermit crabs are rare but still exist today.


Red claws live in shallow water habitats such as mudflats, mangroves, coral reefs, seagrass beds, estuaries, salt marshes, tidal pools, rocky shores, and beaches. They also inhabit freshwater environments including rivers, lakes, ponds, streams, springs, and even aquarium tanks. The most common place for these creatures to reside is near the ocean shoreline. In fact, some people believe that hermit crabs were originally created by God so he would know when his children needed him.


Red Claws Are Found Throughout the World. Red hermit crabs can be found throughout the United States, Canada, Mexico, Central America, South America, Africa, Asia, Australia, New Zealand, and many other countries around the globe.

Although most hermit crabs live only within coastal regions, several species have expanded into freshwater habitats. One notable example is the American river hermit crab. This species was once thought to be restricted to rivers in Florida until it was discovered in New York City’s Hudson River. Another species, the Australian red-clawed hermit crab, was originally believed to be native to Australia before being identified in North America. Today, this species is considered invasive and is now present throughout the United States.


The predators of hermit crabs include birds, fish, snakes, eels, sharks, octopuses, starfish, lobsters, crabs, shrimps, prawns, frogs, salamanders, lizards, and other invertebrates. Hermit crabs can easily escape danger if they hide under rocks or logs. When threatened, they will curl up into a ball with their legs tucked underneath them. Their hard shell protects them from many dangers.


The primary purpose of a hermit crab’s digestive system is to break down organic matter found in the environment. It does this through the use of enzymes and bacteria. Once digested, nutrients are absorbed via the gills located behind each leg. When a hermit crab eats, it will either take in small amounts of sand or algae along with the food item. Sand helps keep the stomach clean and prevents harmful organisms from entering the gut. Algae provide energy for the hermit crab.

Life Cycle

Like many other arthropods, hermit crabs undergo metamorphosis. During early development, young hermit crabs look almost identical to adults except for their claws. As they mature, however, their claws change shape and become longer. Once fully grown, hermit crabs will mate and lay eggs. Females deposit them onto hard surfaces such as stones, coral reefs, and mangroves. Eggs hatch after about five days and then develop through eight stages. Finally, larvae turn into juvenile crabs with soft, spiky limbs. Juveniles stay close to their parents until they are old enough to fend for themselves. At this point, they leave home to find new homes or join existing colonies.


Most hermit crabs reproduce sexually. Males usually court females using elaborate courtship rituals. After mating, males transfer sperm to the female’s reproductive tract via an organ called the gonopore. Female hermit crabs store sperm inside special chambers located between their legs. Each chamber contains millions of sperms which can last up to three years. If fertilization does occur, the developing embryo attaches itself to the mother’s body. It remains attached until hatching occurs approximately seven weeks later. Hatching typically takes place overnight. Some hermit crabs give birth to live offspring rather than laying eggs. These babies grow quickly and begin eating immediately upon reaching adulthood.

red hermit crab
A red hermit crab – Photo by Leo

Relationships With Humans

In addition to being eaten by humans, hermit crabs are sometimes kept as pets. People keep hermits as aquarium inhabitants, decorative items, or scientific specimens. Although hermit crabs are generally docile, they can bite if handled roughly. Also, they should never be fed raw meat.

Feeding and diet

Red hermit crabs feed on dead animals that have been washed ashore. They also eat decaying plants and fungi. In captivity, hermit crabs often consume dried seaweed, lettuce leaves, spinach, alfalfa sprouts, bread crumbs, and cooked vegetables. The most common foods given to captive hermit crabs are shrimp shells, mussels, clams, oyster shells, squid tentacles, and pieces of wood. Crabs prefer these types of food because they contain calcium carbonate. However, some people may offer hermit crabs fresh fruits and vegetables. This type of feeding encourages growth and improves health.

Hermit crabs are opportunistic predators who consume whatever food items come within reach. Their diet consists mainly of dead organisms such as decaying plants, leaves, woody material, seeds, fruits, and fungi.

Other behaviors and adaptations

Some species of hermit crabs use camouflage to hide from potential predators. For example, one species has a shell-shaped like a snail’s foot. Another uses its tail as a shield when it is frightened. Hermit crabs also exhibit social behavior. When threatened, individuals in groups form tight clusters known as “herdings.” A herd member will protect another individual by covering him/herself over with his/her own carapace. Sometimes hermit crabs even help each other out during times of danger. One group of hermit crabs was observed protecting a smaller group of crabs against larger ones.

The hermit crab genus Pagurus includes two subspecies: P. pagurorum and P. graeffei. Both subspecies are native to Europe but were introduced to North America around 1900. Today, both subspecies are found throughout much of eastern Canada and the United States.

Pagurus graeffei is more commonly seen in the wild while P. pagurorum is less frequently encountered. Because of this difference, scientists believe that P. pagurorum originated first. Scientists think that P. pagurronis evolved from P. pagurorum due to changes in habitat. Over time, P. pagurorum adapted to living near human settlements. Eventually, he became so accustomed to life among humans that he lost his fear of people.

Hermit crabs have a variety of defensive mechanisms that help protect themselves from potential threats. They may hide under rocks, logs, seaweed, or debris for protection. Hermit crabs also possess spines along with their bodies that act as weapons. When threatened, these animals often retreat into holes or crevices where they remain hidden. In order to escape danger, hermit crabs may climb out of their shells and run away. This ability allows them to move rapidly through water and land.


In conclusion, we can say that hermit crabs are very interesting creatures. Although many people view them as pests, there are actually several reasons why you should keep an aquarium full of hermit crabs. First off, hermit crabs make great pets if you take care of them properly. Second, hermit crabs provide entertainment value since they perform various activities including eating, swimming, crawling, walking, hiding, and mating. Finally, hermit crabs are beneficial to our environment because they recycle nutrients back into the ocean.

Below is the video about the Scarlet Reef Hermit Crab. Enjoy!

We hope that you found this article helpful when we help you to answer the question about how often do hermit crabs eat. Would you please share any questions or comments below? Thank you!

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