What do sea crabs eat: Characteristics and habits of these crustaceans

Many people are unaware about what do sea crabs eat but nevertheless they love having them in their aquariums or fish tanks.

Crabs are decapod crustaceans that live in the sea. Therefore they have four pairs of legs and powerful claws that they use to hunt.

Main Characteristics of  the Sea Crabs

There are more than four thousand species of crabs, and we find the sea crabs among them. These crustaceans are characterized by being benthic, which means that they make their life on the ocean floor. However, some of these sea crabs, in addition to being benthic, have also acquired the habit of being nectonics that is to say, that instead of living on the bottom of the sea, they live between two depths.

The first pair of legs of the sea crabs evolved throughout the years, to become in a pair of tweezers which are very useful for them. Crabs employ these limbs to capture and manipulate their food, defend themselves from rivals or predators and woo their potential partners.

what do sea crabs eat : crabs´characteristic anatomy

Common Properties of the Sea Crabs

We will begin by pointing out that these crustaceans have a characteristic that is common for all, which is that they are endowed with an exoskeleton made up of chitin, which hardens to become a powerful shell. But as they grow such shell becomes small for them, so they molt it several times during their lives. For example, the shell molting of the horseshoe crab  usually lasts a long period of time, while the rest of the sea crabs usually swallow abundant water to widen their body, and when their carapace has loosened, they begin to extract it slowly and very carefully, since during this process they may lose some of their limbs. Even if they get stuck, they could die.

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What do sea crabs eat?

As we mentioned earlier, the sea crabs have tweezers that allow them not only to capture their preys, but also to manipulate their food. As the crabs grow, so do their pincers, acquiring greater strength and size, which makes it easier for them to capture larger prey. The pincers are used to tear, chop and crush pieces of food such as crustaceans, fish, algae and dead fish that are common prey of the sea crabs. On rare occasions the sea crabs share their food with other specimens of their family. The only exception could be a female with whom they want to mate.

What do sea crabs eat in domestic aquariums?

Sea crabs are opportunists and scavengers, who can eat practically everything, be it algae, fish or even carrion. When they are in captivity, the difference is not much, because they can eat everything that is offered to them. Bread, leaves and petals of flowers, cookies, insects, meat, fruits, vegetables, shells, remains of food. They are sometimes considered a vacuum cleaner, because what is offered to them, they will eat it.

However, sea crabs do not have a digestive system like that of humans, so this type of food is not the most suitable for them, and it can even be harmful. Crayfish  can sometimes adapt better to life in captivity, so we invite you to read our article crayfish, to learn more about them. In the case of sea crabs, it is better to leave them in their natural habitats since these individuals have a hard time adapting to life in captivity.

Sea Crabs Digestive System

The sea crab has a digestive system that is formed by a straight tube, which transforms into a gizzard on its extreme.  Such gizzard has the function of crushing and shredding the food. It also has two glands that secrete digestive juices, which help metabolize food, to absorb nutrients.

As you can see, this digestive system is not similar to that of a human being, and for this reason if you decide to have  a sea crab in your aquarium,  you should provide him with the common food that he eat in their natural environments. Don´t include processed food in their diet so that these crustaceans can live for much longer.

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