Difference Between Crayfish And Lobster

Crayfish and lobster are often mistaken for one another or even at times assumed to be the same thing. While they may seem to appear to be similar at a glance, these two underwater dwellers are pretty different.

Lobsters are found in saltwater, and crayfish are found in freshwater. Crayfish are much smaller than lobsters, and both differ in color. The lifespan of a lobster is longer (up to 50 years) than a crayfish (1-20 years). Their difference in diet and habitat further add to their variance in flavor.

Whether your interest in these crustaceans is purely biological or they relate to your penchant for seafood, there is much to learn about these two clawed species.

Anatomical And Biological Differences Between Crayfish And Lobster

If you were to envision these creatures, they might not appear to have many or any physical differences apart from size. After all, they are both water-dwelling decapods with antennae and a hard shell.

A closer look at these bottom feeders, and you will realize how easy it is to confuse them at first but also wonder how you could have had them mixed up.

Size Of Lobster Vs. Size Of Crayfish

Lobsters are significantly more giant than crayfish, measuring between 8 and 20 inches in length. A crayfish will grow between 2 and 6 inches in length. So even in their infancy, lobsters will always be larger than crayfish.

In terms of weight, lobsters are the heavy hitters when compared to crayfish. Lobsters can weigh between 1-5.5 lbs. although lobsters weighing up to 44 lbs. have been reported. Crayfish weigh between 1.7 -123.5 oz.

Other Physical Differences Between Crayfish And Lobster

While lobsters and crayfish both have claws at the end of their front legs, the claw in question will differ in size. Often the claws of a lobster are far more prominent. Lobster claws are large enough to be eaten as a delicacy on their own when considered a cuisine.

Rock lobsters have other developed physical features that aid them in defense and hunting. However, rock lobsters are entirely devoid of claws. It is for this reason that they are often mistaken for crayfish.

Color Differences Between Lobster And Crayfish

When considering color distinction, there are many contradicting theories and opinions out there. Some argue that the crayfish is the more colorful of the two species, while others will argue the opposite.

The fact is that their colors are not constant and can change due to several factors.

The Color Of A Crayfish

A crayfish’s color will change in accordance with the time of year, their species, maturity, age, location, and diet. Their colors will change from black to orange to red to green. A table compiled and posted by Robert Ceran illustrates the color changes in relation to the seasons specific to the North American regions. You may note that on this table, crayfish are referred to as crawfish. They can also be called crawdads or mudbugs.

The Color Of A Lobster

Factors affecting the color change in lobsters are similar to those affecting the crayfish. A key difference to note is the distribution of a pigment (found in the aquatic plants they consume) called astaxanthin. This pigment is stored in the lobster’s skin but eventually moves to its exoskeleton. The different proteins that are found in the exoskeleton will further cause a change in color.

Eventually, the lobster is left sporting three different layers of color: red on the skin, blue on the shell’s undercarriage, and orange on the outer shell. With all these colors existing on top of each other, lobsters are sometimes mistaken as brown in color.

Due to the fact that lobsters shed their exoskeletons as they grow, the age of the shell will also vary in color. Newer shells will appear lighter, and more rigid older shells will be darker.

Lobsters do exist in a wider variety of colors in comparison to crayfish. Blue, white, and even pastel-colored lobsters have been spotted, but they are quite a rarity. This color phenomenon can be caused by genetics, diet, and location.

Crayfish And Lobsters Difference In Location And Habitats

The most distinguishing difference between crayfish and lobsters is that lobsters are found in saltwater (oceans), and crayfish are found in freshwater (rivers, ponds, streams, brooks, and lakes).

Crayfish Habitats And Geographical Locations

As mentioned, crayfish can be found in any number of freshwater locations, where they keep themselves hidden beneath rocks and logs. If crayfish are found in certain bodies of water, it is generally a good indication of an unpolluted and calcium-rich environment. They are also known to be quite intolerant of water that is polluted.

Geographical locations of crayfish are:

The term “crayfish” is known to be misused in Australia, New Zealand, and South Africa and refers to a kind of saltwater spiny lobster. There are valid species of crayfish found in New Zealand and Australia, but none are found in South Africa. In fact, crayfish can be found on every continent except for Africa and Antarctica.

Lobster Habitat And Geographical Locations

Lobsters mainly live on the bottom of the ocean and are partial to climates between 59-64°F. They are beneath rocks and among the seaweed. This ensures that they are safe from predators and near their food sources. There are between 80-90 different species of lobster. With such a wide variety, it is not surprising that you will find some form of lobster in every ocean in the world.

Differences In The Life Cycles Of Crayfish And Lobster

The lifespan of each crayfish and lobster will depend on the species of each in question. There are many differences in their mating habits as well as the time taken to reach full maturity.

Life Cycle Of Crayfish

  1. Reproduce in the Autumn or Fall
  2. Eggs are laid in the Spring
  3. The eggs are attached to the stomach of the female crayfish
  4. Eggs hatch in 5-8 weeks
  5. The sexual maturity of a crayfish can be reached in a few months or a few years.
  6. The lifespan of crayfish is dependent on their species.

Life Cycle Of Lobster

  1. Female lobsters are ready for sexual reproduction when they reach the age of 5 years.
  2. Sperm is transferred from the male lobster to the female lobster during the summer.
  3. Eggs are only fertilized in the Spring
  4. The female lays up to 3000 eggs
  5. Eggs will remain attached to the bottom of the female’s tail until they hatch several months later.
  6. The larvae swim around for 12 days before molting and gaining enough weight to descend to the floor.
  7. Molting will occur four  times during the larvae stage,
  8. It takes 5-7 years before they reach adulthood.

*Lobsters continue to grow and molt throughout their lifespan

Dietary Habits Of Lobsters And Crayfish

Crayfish and lobsters are both omnivores. Both lobsters and crayfish have a tendency to be scavengers. For crayfish, they rely on a diet of insect larvae, worms, snails, plants, and tadpoles. Lobsters eat seaweed, prawns, clams, fish, and mollusks, and in dire circumstances when food is scarce, they are known to resort to cannibalism.

 It is also said that crayfish will eat their exoskeleton when it has shed in order to retain their calcium level.

Given the differences in their environments and dietary intakes, it is easy to see why they may have a difference in flavor.

Cooking Lobster And Crayfish: Difference In Taste, Texture, And Color

When cooked, the shell of both lobsters and crayfish change color. The lobster will become more of an intense shade of red, and the crayfish resembling a deeper orange color.

The cooked meat of a crayfish is tender and soft but still has a kind of firmness to it. Its flavor is slightly sweeter and has a “meatier” taste.

Seafood connoisseurs will tell you that lobster’s “seafood” flavor is more intense and similar to that of shrimp. Cooked lobster will lack the sweeter taste that you find in crayfish. Instead, they are saltier.

When cooking and serving lobster or crayfish, there are also differences. Given the larger size of lobsters, only certain parts of their body may be served. At the same time, it is not uncommon for an entire crayfish to be served.

Other species that eat crayfish apart from humans include:

  • Raccoons
  • Various birds
  • Water Snakes
  • Turtles
  • Muskrats
  • Red foxes
  • Larger fish
  • Mink
  • Otters

Other species that eat lobster apart from humans include:

  • Large fish
  • Eels
  • Crabs
  • Seals
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Nutritional Differences Between Lobster And Crayfish

It may interest you to know that crayfish contains five percent more calories than lobster. Health practitioners believe lobster is the healthier option for consumption compared to crayfish as they contain high amounts of essential amino acids, vitamin B12, and Omega 3 fatty acids.

Crayfish do contain 59% more fat, 1% more protein, 47% more potassium, 42% more niacin, 71%more vitamin E, and 219% more iron than lobster. Crayfish are also considerably higher in content value when it comes to thiamine, riboflavin, and folic acid. In contrast, lobster contains 3% more water, 22% more sodium, 40% more calcium, and 37% more vitamin B6 than crayfish.

It is ultimately going to be up to you to discern whether or not eating crayfish or lobster is going to affect your health in any way, especially when taking your dietary requirements and lifestyle into consideration. The amount of these foods you consume will also be an important factor. It is a safe idea to stick to the “everything in moderation” rule.

Is There A Way To Tell If You Have Been Served Lobster Or Crayfish?

If dining out at a restaurant, you may find yourself curious or perhaps skeptical about what is stated on the menu and what has been served to you. If the dish you are served contains only the flesh or meat of either lobster or crayfish, the only discernible difference would be in the flavor and texture.

It is likely that your dish has other components, which may make your task of finding either the sweet or salty flavor that much more difficult. Likewise, the texture of the meat may be altered when combined and cooked in different ways.

If whole parts of the crayfish or lobster are being served to you, it will be easier for you to conclude whether or not the crustacean on your plate is the same one mentioned on the menu. The apparent differences in size and color will be distinctive.

Price Difference Between Crayfish And Lobster

Lobster is the more expensive of the two. It has become something of a delicacy and is highly sought after. Besides this, the size of the lobster and the effort that goes into capturing them (when compared to crayfish) is another reason for its high cost.

There is some irony here, considering that lobster was considered a “poor man’s” meal during the colonial era and was even served in prisons. It was so common that one such prison in Boston had to implement a new rule that lobster could only be served three times a week due to the prisoners growing sick (I’m guessing literally and figuratively) from eating it.

In those times, lobsters were easily accessible and thought to be tasteless. Oh, how the times have changed.


When it comes to a cooked lobster or crayfish, they have more similarities than differences. One could easily be swapped out for the other. They are both incredible species in their own way (on or off your plate) and should be recognized and appreciated for their differences.