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Can Blue Crabs Live in Freshwater? (Quick Answers)

Crabs as a dish are quite popular in almost all the coastal communities of the world. But blue crabs are surely an exceptional variety, as it is a very dynamic source of protein.

Blue crabs are commonly found in the Chesapeake Bay of Maryland, Nova Scotia, in the Gulf of Mexico and also on the coasts of Argentina and Uruguay.

Not to mention, commercially Louisiana has the world’s largest blue-crab fishery and these can be harvested all-round the year.

Can blue crabs live in freshwater?

Blue crabs can surely live in freshwater. But for completing the life cycle of blue crabs, the female blue crabs usually need to migrate to salt water to release their eggs. Usually, when the temperature of the water comes down, blue crabs tend to swim towards the warmer water bodies.

Can blue crabs live in freshwater lakes?

Freshwater lake is an ideal estuary for the blue crabs. There are many lakes all over the world where blue crabs are abundantly available. The largest lake of North Carolina, i.e. Lake Mattamuskeet has got plenty of big blue crabs in it. 

Besides, Lake George of Florida is a blue crab fishery hub where these crabs are harvested commercially. The water of Lake George is a mixture of salt and freshwater, which makes the ideal marine environment for the blue crabs. 

The scientific name of blue crab is Callinectes sapidus which means “savory beautiful swimmers”. These crabs are very strong swimmers in nature. Blue crabs are also known as blue claw crabs because of their sapphire-tinted claws. 

On the other hand, blue swimmer crabs and blue legged hermit crab are another two species of crabs. Both of these species of crab are usually marine in nature. 

3 reasons why blue crabs can live in freshwater:

Blue crabs can certainly live-in freshwater and there are multiple facts that make it possible for this marine species to live in freshwater. Check below to know more about them.

Rapid rate of growth:

When blue crabs live in freshwater, they tend to show a rapid rate of growth. This was proven by none other than Dave Eggleston, who is the director of NC State’s Center for Marine Sciences and Technology (CMAST) and professor of marine, earth and atmospheric sciences. 

In one of his experiments, he discovered that the blue crabs demonstrated some record breaking growth rate in freshwater. This is one of the reasons why blue crabs can live in freshwater.


Blue crabs have the ability to adapt as per the drastic changes to their habitat environment. They can survive and cope with any kind of unwanted situation like a change in salinity of the water body.

For harvesting and many other purposes, blue crabs are sometimes brought from oceans to freshwater for which they have to face a change of salinity level in water.

But, they are capable enough to adapt and that’s another reason why blue crabs can live in freshwater.

Versatile food habits:

Blue crabs have a versatile food habit because they will eat almost anything, including lifeless fish, algae and other plant materials, clams, snails, oysters, worms, insects, and mussels.

They are also predacious in nature and that’s why they also tend to eat small crustaceans including its own species who are mostly small, vulnerable and soft-shelled blue crabs.

The versatile food habits of blue crabs is another reason why they can live in freshwater.

How long can blue crabs live in freshwater?

Blue crabs can live in freshwater as long as they remain well-oxygenated. There is no fixed time period for crabs to live in freshwater. To stay alive, blue crabs use their gills to extract oxygen from the water. 

The male blue crabs have the flexibility to live in any kind of aquatic environment. So, they can live in freshwater for an indefinite period of time.

On the other hand, the female blue crabs have to migrate to saltwater as they need a threshold amount of salinity to release their eggs. So, as for female blue crabs, they can live in freshwater till they become sponges i.e. get pregnant.

What type of water do blue crabs live in?

Blue crabs live in both shallow and deeper brackish water. They live in high salinity ocean waters as well.

Moreover, blue crabs can also live happily in freshwater. The Atlantic coast and the Gulf of Mexico are the two such hotspots where blue crabs can be found in abundance. 

An ideal aquatic environment which contains an adequate amount of oxygen in the water, food that is suitable for the marine crustaceans, and has the salinity from 40 to 0 ppt, blue crabs can easily live in that kind of environment.

Blue crabs are commercially harvested in many parts of the world in freshwater. 

How to raise blue crab in freshwater?

You can easily raise blue crabs on your own just by following a few easy steps. Some common precautions and tips are very much essential for raising blue crabs in freshwater.

Otherwise, the crabs might lose their life if they do not get the suitable environment to grow up. Follow the steps below thoroughly to raise your blue crabs in freshwater:

Catching the small blue crabs:

The first and foremost thing you need to do is catch some blue crabs from your nearby ocean. You have to be very careful in selecting the crabs. 

Make sure that the crabs are small enough and not fully mature. You should also ensure to collect adequate specimens of both male and female blue crabs in order to raise them in freshwater. It would maintain a nominal balance of population.

Selecting a freshwater medium for the crabs: 

A clean pond is an ideal choice for raising the blue crabs in freshwater. So, after you are done catching the crabs from a viable source, put the crabs in the pond. 

Arranging the suitable food for the crabs: 

The blue crabs need few food items to stay alive in the freshwater. Algae is the most feasible food for the blue crabs. 

To create an appropriate habitat and providing proper nutrition to the blue crabs, pour a bucket of algae to the pond everyday.

Try to collect the algae from your nearest river, lake or ocean and ensure that the algae is reproducing itself after you have discharged them into the pond. 

The blue crabs approximately take 105 days to mature fully. So remove the blue crabs from the pond after they reach their adulthood. 

When do blue crabs need saltwater?

Male blue crabs don’t need saltwater for any specific purpose. But females do need saltwater for reproduction. When the female crabs need to release its eggs, at that time, they need saltwater.

After passing their larval stage, blue crabs develop a hard shell in their early life. In every growing stage, the blue crabs tend to molt. Molting is basically a process of shedding or casting off the shell. 

During molting, the soft-bodied larva comes out of the hard shell by splitting the exoskeleton. The infant blue crabs then swell up by absorbing water. The exoskeleton i.e. the hard shell again starts to develop gradually.

This exoskeleton needs saltwater as the calcium in it will make the outer covering of the shell hard and strong. So, the blue crabs need saltwater in order to complete their life cycle.

Could I put blue crabs in my pond?

You can definitely put the blue crabs in your pond. Among all the aquatic ecosystems in the world, the pond is considered to have the most accurate aquatic environment for the blue crabs. 

From research, it was proven that the habitat structure of the pond ensures a 12% raise in the growth rate of blue crabs.

As the blue crabs have the ability to adapt with different aquatic environments, they can easily adapt in pond habitat. So, if you want to raise blue crabs, put them in your nearest pond without any worries.

Can blue crabs be farm-raised? 

The blue crab can be very well-raised in farms. Currently, the natural habitat of the blue crabs are getting affected due to the massive population and the growing pollution in water bodies.

That’s why, scientists have made a thorough research and found that the blue crabs can easily be grown in small farms. 

Many might think that the farm-raised blue crabs and the ocean ones might differ in taste and deliciousness.

But that’s completely a wrong concept. The farm-raised blue crabs and the ocean blue crabs have absolutely no difference in taste. The farm-raised ones are as mouth-watering as the ocean ones. 

Tap water is also suitable for raising blue crabs. Just make sure that the crabs are well-oxygenated and their gills are moist enough for smooth respiration. 

The blue crabs usually can’t tolerate cold water as they like warm water bodies with a basic temperature.

Final Thoughts

There are different types of crabs around the world. However, blue crab is surely an exceptional marine crustacean. It is an ideal choice for feasting for sea-food lovers. Apart from its ability of versatility in coping with different habitats, it is abundantly available and can live in freshwater.