Crayfish vs Crawfish: Unraveling the Mystery of These Aquatic Creatures

Crayfish and crawfish are terms often used interchangeably to describe a group of freshwater crustaceans. They resemble small lobsters and can be found in a variety of aquatic habitats, such as rivers, lakes, and streams. The distinction between these terms is mainly geographic: in the United States, “crawfish” is more commonly used in the South, while “crayfish” is favored in the North and other regions.

These crustaceans play an essential role in aquatic ecosystems, serving as a critical food source for many fish, birds, and other animals. They are omnivorous, consuming a diverse diet that includes plant matter, insects, snails, and even small fish source. As a key part of the food chain, their population dynamics can significantly impact the overall health and balance of the ecosystems they inhabit.

Crayfish and Crawfish: Understanding the Terminology

Language and Regional Differences

Crayfish and crawfish are two terms used interchangeably to describe the same small crustacean species. The differences in terminology stem from the regional variations in language:

  • Crayfish: This term originated from the Old French word “crevice” and is more commonly used in Northern regions, such as the United States and Canada.
  • Crawfish: Predominantly used in Southern states of the US, particularly in Louisiana where they are a staple in local cuisine.

Scientific Classification and Naming

Crayfish and crawfish both belong to the family Astacidae. Members of Astacidae are freshwater crustaceans closely related to lobsters. To better understand their classification, here is a comparison table of the scientific taxonomy:

Classification Crayfish/Crawfish
Kingdom Animalia
Phylum Arthropoda
Class Malacostraca
Order Decapoda
Family Astacidae

While there are several species within the family Astacidae, they are all grouped under the common names of crayfish and crawfish – regardless of regional vocabulary.

Some notable characteristics of crayfish/crawfish are:

  • Ten appendages: 4 pairs of walking legs and 1 pair of pincers
  • Lobster-like body, including a tail fan flattened from top to bottom
  • Found in freshwater environments like lakes, rivers, and streams

When distinguishing between crayfish and crawfish, remember that the terms refer to the same crustacean and the usage varies based on regional language preferences.

Similarities and Differences of Crayfish and Crawfish

Appearance

Crayfish and crawfish are terms that refer to the same freshwater crustacean. They are small, lobster-like creatures with hard shells and ten legs. Some of their distinct features include:

  • Two large front claws
  • A fan-shaped tail
  • Four pairs of walking legs
  • Gills for breathing

These creatures come in various colors, ranging from brown to vivid red.

Habitat and Distribution

Crayfish, also known as crawfish, freshwater lobsters, or mud bugs, can be found in different types of aquatic habitats:

  • Rivers
  • Streams
  • Brooks
  • Swamps
  • Ponds
  • Lakes

They mainly inhabit the United States and North America, and they are especially common in regions such as the West Coast, Oklahoma, and Kansas.

Crayfish are known to be omnivores, feeding on algae, small fish, and insects. They act as both predators and prey within the ecosystem.

Comparison Table

Features Crayfish/Crawfish (same)
Appearance Lobster-like with hard shell and ten legs
Habitat Freshwater lakes, rivers, streams, ponds, and swamps
Distribution United States, North America
Diet Omnivorous
Role in Ecosystem Both predator and prey

Their similarities in terms of appearance, habitat, and distribution indicate that crayfish and crawfish are different names for the same freshwater crustacean.

Culinary Uses and Impact on Culture

Louisiana Cuisine

Crayfish, also known as crawfish or crawdaddies, hold a prominent place in Louisiana’s culinary heritage. They are a key ingredient in many traditional dishes, especially in Cajun cuisine. Some popular examples include:

  • Crawfish étouffée: A stew-like dish with a spicy, flavorful roux and aromatic vegetables.
  • Crawfish boil: A social event that involves boiling large quantities of crawfish with spices, corn, potatoes, and other vegetables.

Crayfish and Crawfish Dishes around the World

While Louisiana is famous for its crawfish dishes, other countries also have their unique takes on preparing these crustaceans:

  • Australia: Yabbies, a type of crayfish, are prepared in various ways, such as grilling or adding them to salads.
  • Singapore: Chili crayfish, a dish similar to chili crab, features stir-fried crayfish in a flavorful and spicy sauce.
  • Sweden: Crayfish parties or Kräftskiva are outdoor gatherings where people enjoy boiled crayfish, often seasoned with dill.

Preparation Methods and Recipes

Crayfish can be cooked using different methods, with some popular options being:

  • Boiling: The most common method, used in dishes like Louisiana crawfish boils.
  • Grilling: Crayfish can be split in half, cleaned, and grilled with butter and herbs.
  • Sautéing: In dishes like étouffée or bisque, crayfish tail meat is often sautéed with aromatic vegetables.

Pros of Using Crayfish

  • Versatile and flavorful ingredient in various cuisines
  • Rich source of protein and lower fat content compared to some other types of seafood

Cons of Using Crayfish

  • Limited availability in some regions
  • Labor-intensive preparation, as it involves cleaning and deveining
Ingredients Louisiana Crawfish Australian Yabbies Singapore Chili Crayfish
Crustacean Crawfish Yabbies Crayfish
Spices Cajun spices Varies Chili, garlic, ginger
Cooking method Boiling Grilling Stir-frying
Accompaniments Corn, potatoes Salads Rice

Environmental and Conservation Issues

Aquatic Life Impact

Crayfish, also known as crawfish or crawdad, are freshwater crustaceans found predominantly in the United States, particularly in the southeastern regions. Their impact on aquatic life is significant, as they contribute to the overall health of the ecosystem by serving as both a food source and a scavenger of dead and decaying matter.

  • Diet consists of twigs, dead fish, decaying vegetation, frogs, and small turtles
  • Predator examples: raccoons, fish, and birds

Despite their mostly positive impact on aquatic life, some crayfish species are at risk due to habitat loss and environmental threats, like the Shasta crayfish, which has seen significant decline in California.

Invasive Species and Their Effects

There is a growing concern over invasive crayfish species, such as the Procambarus clarkii (red swamp crayfish), which can have negative consequences on native crayfish populations and ecosystems:

  • Competes with native species for food and habitat
  • Increases sedimentation through burrowing activities
  • Overgrazing on aquatic vegetation, decreasing water quality

Comparison table of native versus invasive crayfish:

Native Crayfish Invasive Crayfish
Essential to ecosystem health Harmful to ecosystem
Serves as food and cleans up dead matter Competes with native species for resources
Limited impact on vegetation Alters vegetation through overgrazing

Efforts are being made to protect native crayfish species and their habitats. For example, critical habitats have been designated for the Big Sandy and Guyandotte River crayfish in Kentucky, Virginia, and West Virginia to curb the effects of erosion and reduced water quality.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Crayfish missing its claws

 

Weird looking yard bug found today-Shrimp?
Mon, Mar 9, 2009 at 10:16 AM
My wife found this bug on our yard this morning. We live in Tampa, FL and I’ve never seen one of these on my lawn. Looks a lot like something between a freshwater shrimp and a crawfish.
Pat Ryan
Tampa, FL

Clawless Crayfish
Clawless Crayfish

Dear Pat,
This is indeed a Crayfish or Crawfish, but alas, some trauma has caused it to lose its claws.  Fear not, the claws can grow back, but the poor crustacean is helpless until the regeneration.

Letter 2 – Crayfish, or Crawfish, or Crawdad, or Clawfish

 

What is this bug??????
August 4, 2009
Please help me identify this bug! This is the second in a week of these things that has appeared at my house in South Florida. They look like mini lobsters with scorpion pinchers. Are they something to be worried about?
Mike Paulson
South Florida

Crayfish
Crayfish

Hi Mike,
This is a Crayfish and it is a Crustacean and there is nothing to worry about.

Daniel:
Hmmmm.  I guess it is!  Given the amount of rain we are having in Florida, the preserve behind my house has water in it, where it doesn’t usually.  I guess that’s causing crayfish to move in.
Thanks for the clarification!
Mike

Letter 3 – Crayfish and Fly

 

Subject: Spider or crayfish?
Location: Indianapolis, indiana
June 22, 2016 4:36 pm
Came across this critter flipped over, struggling at the edge of a creek. Managed to take this photo of the ventral side, but some kids crushed it with a rock before I could turn it over. It was quite big, four or five inches at least, large enough that I could have cradled it in my hand. Looking at photo, it appears to have eight legs, but spiders in this region are not normally this big or robust, so my guess is that it was a crayfish and that the other limbs are not apparent in the photo and/or were pulled off by something.
Signature: Anonymous

Crayfish and Fly
Crayfish and Fly

Dear Anonymous in Indianapolis,
This is most definitely a Crayfish (Crawfish, Clawfish or Crawdad) and it appears to be missing its claws or more correctly, its Chelipeds.  Though it is not very distinctive, we are curious about the identity of the Fly in the upper right corner of your image.  We hope we never hear again about the kids who crushed it.

Letter 4 – Crayfish Burrow

 

What’s that nest?
Hello,
We have spotted two nests in the yard of a home we’re looking to purchase in southern Illinois that we’d like to have identified. The picture shows one of these nests from above. The nests are pillar-like, and knobby, not just piles of dirt. At the core of the pillar is a hole that’s approximately 1 inch in diameter, the opening of a tunnel that runs into the yard, evidenced by a curvy path of dead grass. The tunnel is not soft like that of a mole. Any ideas? Thanks!
Kevin
Dayton, OH

Hi Kevin,
Your hole sure looks like a Crayfish burrow to us. These lobster-like crustaceans will bury themselves in the mud when their ponds dry up.

(04/08/2005) Crayfish Burrow
I would like to open by saying that I look at your website a lot and find it very fascinating. Thanks for a great service. I have never mailed before but I had to respond to a picture that you put up today. I am born and raised in New Orleans, Louisiana and would like to offer some info on the picture titled ” Crayfish Burrow (04/07/2005) What’s that nest?” You are correct that is a crayfish hole or down here better known as a Crawfish. We have them anywhere near fresh water and they are great to eat!
Thanks again.
Maureen

Letter 5 – Crayfish, but is it real or is it a rubber lure???

 

(Never seen one like this)
Location:  Charlottesville, VA
July 24, 2010 8:08 pm
Hello Bugman,
The bug seen in the picture below was seen while going for a hike on the Ragged Mountain trail in Charlottesville, VA. It was about 3-4 inches long, and was perched on a stick above the water.It did not move while I observed it, so I am not sure if it emerged from the water or how long it had been there. I go hiking in this area and in Shenandoah quite a bit, and while I have seen some odd insects, I have never seen one quite like this (if it even is an insect). Please enlighten me as to the nature of this strange beast. Thank you for your time, and please keep up this ”labor of love” for as long as you are able, it truly is an invaluable service.
Peter Oliver

Crayfish: Simulacra or the Real McCoy???

Hi Peter,
Our co-worker Amy told us to expect your email.  This is a Crayfish, a freshwater crustacean that goes by some other local names, including Crawfish, Crawdad, and Clawfish, but our real question is whether it is a real dead Crayfish left behind by a fisherman, or perhaps a Crayfish Fishing Lure made of of rubber, which is our first choice.  Crayfish are eagerly eaten by big fish like Largemouth Bass, and we suspect lures are readily available in shops catering to the needs of fishermen.

Ah, I see!  No wonder it looks like a prop left over from the first Alien movie; I had a hunch it was an unnatural critter.  Thanks for getting back to me so quickly, I think we met at Amy’s wedding but the whole trip is kind of blur.  I appreciate your input, and will share it with my fellow hikers who were also puzzled by its presence.  Thanks again!
Peter

Letter 6 – Crayfish Claw, we believe

 

Subject:  Found bug claw in clean laundry
Geographic location of the bug:  North Florida
Date: 04/01/2018
Time: 06:54 PM EDT
Your letter to the bugman:  I found a brown 1″ long pincer claw hanging onto a sock in my laundry. Any help figuring out what bug it could have belonged to is appreciated!
How you want your letter signed:  Grace

Crayfish Claw

Dear Grace,
This looks to us like the claw of a Crayfish, a small, freshwater Crustacean that resembles a lobster.

Letter 7 – Crayfish from Australia

 

Subject: Strange bug!
Location: Fern Tree Gully, Victoria, Australia
October 28, 2012 6:55 am
Hi!
While walking through the Fern Tree Gully reserve in Australia, we came across a strange bug. It looked like it was trying to burrow down into the soil.
There was a creek near by, so we also wondered if it was some kind of crab/lobster type bug that perhaps a bird had just picked up and dropped?
Never seen anything like it. Hopefully you can help identify!
Thanks a lot
Signature: Jason OConnor

Crayfish

Dear Jason,
This is a Crayfish, an aquatic, freshwater Crustacean that burrows into the mud and is able to survive periods of drought underground.  It appears that this Crayfish is missing its front claws, however, they are able to regenerate.  According to Encyclopedia Britannica:  “Lobsters and crayfish regenerate claws and legs in a straightforward manner as direct outgrowths from the stumps. As in other crustaceans, however, these regenerates lie immobile within an enveloping cuticle and do not become functional until their sheath is shed at the next molt.”

Letter 8 – Crayfish: Mangled by Dog or Dispatched by Dog Owner?

 

Found in some leaves
Wed, Mar 11, 2009 at 7:09 PM
I found my dog attacking one of these last night and it sure does look like a scorpion to me, but living in Indiana I have been led to believe that they are not native to this area. We have recently had a lot of water activity and this was found nighttime on cement…i think they are living in some leaves that blew onto the cement. I would really like to get at least an idea of what type of bug this is.
Ashley H.
North Eastern Indiana

Crayfish Carnage
Crayfish Carnage

Hi Ashley,
This is a Crayfish or Crawfish, or Crawdad in the South, a freshwater Crustacean that can survive on land, in damp conditions, that is found throughout much of the U.S.  We are uncertain if the mortal wounds were inflicted by your dog or by you, but we are posting this image to our Unnecessary Carnage page nonetheless.  Crayfish are edible and taste much like lobster.

Letter 9 – Crayola Katydid

 

Subject:  Locust in Peru
Geographic location of the bug:  Amazon jungle of Peru
Date: 11/14/2017
Time: 04:16 PM EDT
Beautiful bug, a kind of locust or similar, but I can’t identificate it.
The photo was on august 2009.
Thanks for helping.
How you want your letter signed:  Ferran Lizana

Crayola Katydid

Dear Ferran,
The blue and red legs on this Katydid are very distinctive.  We found a very similar looking individual posted to Alamy that is identified as a Crayola Katydid,
Vestria species, but the abdomen appears to be striped unlike your individual.  Gil Wizen, entomologist and photographer has a similar image posted to his site and he writes:  “As adults, the Vestria katydids take a different look completely. They are no longer flat and look like the huntsman spiders. In this stage they are known as rainbow katydids or crayola katydids because of their striking coloration, which is an advertisement of their chemical defense against predators.  When provoked, Vestria katydids curl their body and hunker down, revealing a brightly colored abdomen. They also expose a scent gland from their last abdominal tergum and release a foul odor that is easily detectable from a close distance. Different species of Vestria have different odors, and from my personal experience I can attest that some species smell as bitter as bad almonds while others smell like a ripe peaches. The compounds released are pyrazines, and there is evidence that this chemical defense is effective against mammalian predators such as monkeys. While many katydids have bright aposematic coloration, Vestria species are one of the only examples of katydids successfully deploying chemical defense against predators, making them distasteful. But don’t listen to me, I actually like peaches.”  Terry Wild Stock Photography has an image of an individual from the genus that most closely resembles your individual.  

Oooh!! You are great!!
What a strange species, I’m very happy to had been taken this picture!!
X)))

Letter 10 – Crayola Katydid from Belize

 

Insect from Belize…
Location:  Mountain Pine Ridge in Cayo, Belize
July 28, 2010 10:21 am
We think it’s a sort of locust, what do you think? We were fascinated with this bug! I took this picture on Thursday, July 22, 2010. Thanks for your help!
Sandie Young

Crayola Katydid from Belize

Hi Sandie,
This appears to be a Katydid, though we sometimes mistake other Long Horned Orthopterans in the suborder Ensifera for Katydids.  We are going to check with international Katydid expert Piotr Naskrecki to see if he recognizes your species.

That is wonderful, thank you so much.  Will you please let me know what you find out?  I’ve never seen such a beautiful colorful bug !  🙂

Hi Daniel,
This is a female of the Crayola katydid, Moncheca pretiosa (Tettigoniidae: Conocephalinae), one of the few katydids that probably uses chemical defenses. Although this species has not yet been tested, its closest relative,  a similarly colored genus Vestria, produces volatile pyrazines that are known to act as repellants to monkeys and birds.
Cheers,
Piotr

Wow Piotr,
That is wonderful.  The Crayola Katydid sure has a fitting name for such a colorful Katydid, and those of us who grew up with the 64 pack of crayons appreciate the significance.

How cool is that!!  I love his name.  We were calling him the disco bug 🙂  Thanks for the info !  What a great website you have !  🙂
Sandie

Letter 11 – Red Admiral Supplants Crayfish as photo subject

 

Subject: Red Admiral butterfly
Location: Mercer county NJ
October 7, 2012 3:04 pm
I’m more and more amazed at the butterflies I keep finding as I actually start to look for them. I usually go crayfish hunting at lunch and have gotten some very nice pictures like the one below and sometimes a new addition to my fish tanks.I’ve almost stopped looking for crayfish the last couple of months to try and find, identify and take pictures of new butterflies before the cold weather kills them or forces them to migrate. My latest is this Red Admiral. As always thanks for being such a great source of information and great pictures
Signature: David from NJ

Red Admiral

Hi David,
We are happy to hear you find our website so helpful and we are definitely benefiting from your fine photographic additions.  Your Red Admiral photo is quite lovely.  Though many Red Admirals migrate, we thought we recalled information that Red Admirals may hibernate as well, and we found some information on the Convention on Biological Diversity website, though that British website is speaking about the Eurasian population of this species since Red Admirals are found throughout the northern Hemisphere.  The site states:  “Some individuals don’t migrate, especially when there is a gentle winter. They will hide in small holes and hibernate waiting for warmer days.”  We are very intrigued with your interest in crayfish.  When in our childhood, we had a small crayfish in a tropical aquarium, but it was returned to a local pond after it caught and ate our Serpae Tetra.  Just yesterday we made a trip to the local aquarium store, Tropical Imports, and we noticed they had several red crayfish that resembled boiled lobsters in color.

Crayfish

I’ve been studying/collecting crayfish for about 3 years now. I’ve learned to identify the species from NJ and a few others. It’s a fun hobby and ties in well with my other hobbies of fishing and exploring the outdoors. I always find myself turning over rocks and logs in and along the water so I tend to come across a lot of wildlife. That’s where Whatsthatbug comes in so handy. Between your website, various forums and state wildlife sites I’ve done a pretty good job of educating myself (hurray internet lol).
So thank you again for having such a great site and such friendly staff. The red crayfish you saw at the pet store are most likely Procambarus clarkii commonly called the Red Swamp crayfish. They are the ones you see at crayfish boils in Louisiana and are very common down south. I have the dubious distinction of being one of the few people to know that they are found in NJ now as an invasive species.


Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

9 thoughts on “Crayfish vs Crawfish: Unraveling the Mystery of These Aquatic Creatures”

  1. Mike,

    You need to find somebody that can get you some pond grown crawfish, or crayfish depending on where your from. The tails are good in a gumbo or by themselves. Boil them, like a lobster, and get some Cajun seasoning to go with it. Bon apetit.

    Reply

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