Velvet crabs are medium-sized crabs found in British coastal waters. Depending on your background or interest, you can call them velvet swimming crabs, lady crabs, devil’s crabs, or ‘fighter crabs.’ That’s not all. Scientists or people with a deep interest in science often refer to this swimming crab as the Necora puber.

Many people have considered this swimming crab a pet species for years. However, due to the advancement in knowledge about their characteristics, habitat, reproduction, and much more, that is changing fast. Due to their dietary value, these crabs are currently deemed one of the most important commercially viable export species in Ireland, the United Kingdom, and many other places.

This article provides up-to-date information about the velvet swimming crab. It has been designed to empower every reader who intends to understand the value of this crab and gain useful insights on the best ways to protect it from serious threats like habitat destruction, overfishing, and ocean acidity.


The name ‘velvet swimming crab’ indicates this animal’s appearance. It has a velvet appearance. How? The short hairs that cover the crab give them a velvet appearance. These animals are also amazingly soft to the touch, like the woven, tufted fabric known as velvet.

Like other species of swimming crabs, the rear-most legs of these velvet-like sea creatures are flattened exactly like paddles, empowering them to swim against tides and currents. Because of these well-adapted rear-most legs, velvet crabs have above-average speed underwater, meaning they are aggressive at catching various swimming prey.

Many experts think this aggressiveness has earned it the common nickname, ‘the devil’s crab.’

If you want other ways other than the short hairs to identify velvet crabs, think about their distinctive bright red eyes.

Velvet crab's distinctive red eyes
Velvet crab’s distinctive red eyes

It would be best if you also remembered that the body parts of their bodies are usually multicolored, ranging from brown to green. Nonetheless, you can see bright-orange velvet swimming crabs in a few cases.

If you are asking about the size of adult velvet swimming crabs, it’s between 8cm and 9 cm across the shell.


Velvet swimming crabs are available in large numbers throughout European waters. You can find them in Ireland and UK coastlines, particularly in places where there are rocky and broken grounds.

Velvet crab underwater
Velvet crab underwater

Moreover, you can find these swimming crabs in offshore waters down to depths of about 100 meters.


Do you recall that the velvet crab uses its rear-most legs to feed? Yes, they enable the crab to catch swimming prey. Some of these prey are fish and prawns. At the same time, velvet crabs use these legs to munch on sea snails, clams, worms, and other easier catches.

Other than that, these crabs can feed on dead animals whenever they don’t catch their prey.


Research shows that a velvet crab can reproduce after its first year. Females carry fertilized around.

If you see a swimming scrap with the features we’ve seen above, plus a mass on its underside, don’t worry. That’s a female velvet swimming scrap carrying its fertilized eggs around to protect them from hungry predators.

After hatching, the young crabs can live for between four and five years.


Due to velvet crabs’ commercial value, some anglers have overfished them. Most use pot and trap fishing methods to capture this species in unstainable numbers over a short period.  

There are concerns that UK, France, and Spain fishers have perfected the art of using these unstainable fishing techniques.

Anglers sometimes mistakenly catch the velvet crab. Some of them still view them as bait-stealing pets. So, they kill them without any valid reason. So, we need tighter regulations to protect the available stocks.

A few enlightened fishers return young velvet swimming crabs un-harmed. Others take the males and return the females to replenish their stock. At the same time, some anglers only have mercy on females carrying eggs. These actions should be encouraged, and the anglers should be appreciated.

However, we need to do more than that. The increasing ocean acidification destroys the red-eyed crab’s exoskeleton (external skeleton). This shows that the ocean needs more attention.

Facts about Velvet Crab

  1. The velvet swimming crab is not as soft as the name implies in every aspect. Its aggressive behavior is thought to have resulted in a funny nickname, the devil’s crab.
  2. The red-eyed crab is distinguishable from other crab species by their rear flat paddle-like flippers that aid in swimming, the color of the eyes, and the body covered with hair, giving them a velvet appearance.
  3. These swimming crabs are small but tasty.
  4. The velvet swimming crab’s shell is 10 cm, but the body is 8 and 9 cm across the shell.
  5. Female velvet crabs carry fertilized eggs all the time to protect them from hungry predators.


How long do velvet crabs live?

Velvet crabs live for between four and five years in the wild. The female can reproduce up to 250,000 eggs per season and protect them to prevent predators from eating them. So, one velvet swimming crab can release at least one million offspring in her lifetime. Her offspring begins to reproduce about one year later, and the circle continues.

How are microplastics a threat to velvet crabs?

Due to widespread contamination, velvet crabs ingest microplastics in large numbers every day. This causes a serious problem because these pollutants are associated with chemicals that poison the environment. So, many velvet swimming crabs that consume them are at risk of suffering from terminal diseases, which in turn present a direct threat to humans who consume the affected animals.

How can I conserve velvet crabs?

You can conserve velvet swimming crabs using sustainable fishing practices, like pot fishing. If you capture young or female velvet crabs, consider returning them to the sea unharmed. You should do the same if you unintentionally capture this crab species. At the same time, be sure you preserve the environment to limit ocean acidification, which harms the animal’s external skeleton.

Can you eat a velvet crab?

You can eat a velvet crab even though it’s more difficult to prepare than the larger brown crab. Other than the preparation process, its meat is delicious. Fishers in Northern Ireland, Scotland, and Cornwall catch them alongside the brown crabs. However, in some places, fishers specifically target this crab species, giving cooks plenty of options in the kitchen.

About Ocean Info

At Ocean Info, we dive deep into ocean-related topics such as sealife, exploration of the sea, rivers, areas of geographical importance, sailing, and more.

We achieve this by having the best team create content - this ranges from marine experts, trained scuba divers, marine-related enthusiasts, and more.

Sea Anemone with Clownfish

Dive into more, the ocean is more than just a surface view

Bottlenose dolphins are known to help stranded humans back to the shore

8 of the Most Intelligent Marine Animals

From dolphins' awe-inspiring communication skills to orcas' social complexity, the ocean is home to some of the most intelligent marine animals.

Share to...