Even though Cambarellus shufeldtii (also known as Cajun Dwarf Crayfish, and Swamp Dwarf Crayfish) is pretty common in North America, these small crayfish are rather rare on the pet trade market yet.
In my opinion, this is one of the most underrated and overlooked crayfish species in the aquarium hobby. Why?
Because Cambarellus shufeldtii is easy to breed and care for. They do not require frequent water changes or a huge tank, and they are one of the most peaceful crayfish species (by crayfish standards of course) you can ever find.
These small animals compensate for their size with personality and tons of energy.
Keep reading for more information about these amazing pets and how to care for Cambarellus shufeldtii in your home aquarium.
Quick Notes about Cambarellus Shufeldtii
| Name | Cambarellus shufeldtii |
| Common Names | North American Cajun Dwarf Crayfish, Cajun Dwarf Crayfish, and Swamp Dwarf Crayfish |
| Scientific Name | Cambarellus shufeldtii |
| Tank size (optimal) | 10 gallons (~40 liters) |
| Keeping | Easy |
| Breeding | Easy |
| Size | up to 3.5 cm (~ 1.5 inches) |
| Optimal Temperature | 20 – 24°C (~68 – 75°F) |
| Optimal PH | 5.4 – 7.4 |
| Optimal GH | 3 – 18 |
| Optimal KH | 3 – 15 |
| Nitrate | Less than 20 ppm |
| Diet | Detritivore / omnivore |
| Temperament | Conditionally Peaceful |
| Life span | up to 2 years |
| Color Form | Brown/reddish to blue with two distinct color patterns (spotted and striped) |
Origins and Natural Habitat
Cambarellus shufeldtii is a species of crayfish in the family Cambaridae.
This is a freshwater crayfish native to the Gulf Coastal Plain of the United States which includes the states of Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, and Texas.
This species has a large distribution and is able to inhabit a wide range of habitats. For example, it is present in Georgia as an introduced species.
In nature, Cambarellus shufeldtii prefers habitats with standing to slow-moving shallow water, including swamps, marshes, lakes, ponds, ditches, sluggish streams and slow rivers.
This species favors shallow water with plant cover.
Description
Cambarellus shufeldtii is pretty small compared to some of the other crayfish species available in aquarium stores.
They can grow up to 1.5 inches (about 3.5 cm) long; however, the average size is around 1.25 inches (3 cm), with females being slightly larger.
The claws are narrow and long.
Cambarellus shufeldtii has dimorphic color patterns that make them really hard to identify. Some individuals are brown, some more reddish, some tan with reddish claws. Background color can be tan to light brown, and some individuals may have longitudinal dark stripes on the carapace and abdomen.
Blue strains of this species also exist. For example, according to the study, they can have several bluish color patterns:
- A spotted form, characterized by several rows of dark steel-blue spots on the dorso-lateral surfaces of the carapace and abdomen.
- A stripped form, characterized by several rows of dark steel-blue stripes alternating with pigmentless stripes of equal width running the length of the carapace and abdomen.
There is no intermediate or blending of the two patterns.
Note: Their color is variable and it also changes as they grow and molt. Also, some crayfish owners are still trying to create a pure blue strain. Unfortunately, those Cambarellus shufeldtii are not yet breeding true yet. It means that not all color characteristics are passed from parents to offspring.
As with many crustaceans, Cambarellus shufeldtii do not really show any color when they are young.
Lifespan
Cambarellus shufeldtii live rather short lives of no more than 15 – 18 months (up to 2 years in captivity under optimal conditions).
According to some studies, females live about 1 year or so during which they may have at least two broods. Their lifespan is probably dependent on physical exhaustion because of the high energetic costs associated with breeding in species with direct development.
In a poorly maintained aquarium, these crayfish can suffer and die prematurely.
Cambarellus Shufeldtii and other Dwarf Species of Crayfish
According to some studies, there are 19 species belonging to the genus Cambarellinae.
They are all pretty small and may look quite similar. So, differentiating them is almost impossible unless you are a professional biologist.
Of course, some people may disagree and say that there is an easier way and these species have different coloration and/or color patterns, for example:
1. Cambarellus ninae – brown-colored.
2. Cambarellus montezumae – yellow-colored.
3. Cambarellus patzcuarensis – orange-colored.
4. Cambarellus shufeldtii – grey/reddish to brown-colored.
5. Cambarellus texanus – olive to brown-colored.
6. Cambarellus diminutus – grey/reddish to dark grey.
7. Cambarellus puer – orange-red to light brown.
The only problem is that this method of “classification” is not accurate and, in some cases, it is totally compromised. Why?
Because color can vary even within the same species! Their diet can also affect coloration. We also have a culling (selection).
Moreover, many species of the genus Cambarellus have been found to hybridize (crossbreed) in the wild creating some new color variations and patterns. Actually, some aquarists use it to create new color morphs.
Under these circumstances, it makes really hard to find out what kind of species you might have in the tank.
Behavior
Cambarellus shufeldtii has some fascinating behavior and personality.
In the absence of large or aggressive fish, they are pretty active and not timid at all. Even though you will often see them crawling around the tank day and night exploring, they are still considered to be nocturnal animals.
Cambarellus shufeldtii is also outgoing crayfish. They are a lot more social than other species. Unlike Dwarf Mexican crayfish that will not tolerate another male where they can see them, generally, it is way easier with Cambarellus shufeldtii.
Of course, they can spar with each other at times (mostly because of the food). However, they usually do not damage and prefer to retreat.
In nature, they can burrow during dry periods, however, Cambarellus shufeldtii is not an obligate burrower. Given a chance, they mostly occupy the existing ones and hollow out these cells.
They are not messy and/or destructive. These crayfish will not redecorate your aquascape to their liking.
They are fantastic aquarium invertebrates and always fun to watch.
Features:
- Social: Yes
- Active: Yes
- Peaceful: Yes (generally)
- Burrowers: No (generally)
Feeding Cambarellus Shufeldtii
Cambarellus shufeldtii are natural-born scavengers. They are omnivores and opportunistic eaters that will eat anything they can find!
In captivity, for the best growth, they need a good mix of meats, vegetation, and calcium. I would say that their feeds should contain protein at a level of about 30 – 40% of the diet.
Foods Cambarellus shufeldtii will enjoy (examples with links to check the price on Amazon), for example:
- Shrimp pellets.
- Shrimp Granules.
- Fish food (TetraMin® flakes, etc.)
- Shrimp food (Hikari’s crustacean food like Hikari Shrimp Cuisine, etc.)
- Vegetables (broccoli, cabbages, carrots, cucumbers, lettuce, corn, spinach, peas, squash, leafy greens, etc.).
- Fruits (Apple, banana, pearl, melon, mango, etc.).
- Leaves.
- Frozen blood worms.
- Detritus worms.
- Brine shrimp.
- Tubifex worms.
- Blackworms.
- Earthworms.
- Freshly crushed snails.
- Dead fish or shrimp, etc.
Leaves (for example, Almond leaves, dead beech, oak leaves, etc.) should always be on the menu, as they feed on these and require the detritus from the leaves.
It is absolutely important to supplement their diet with eggshells, cuttlebone, etc. Also, make sure they get enough calcium (for the exoskeleton) by regularly feeding specialized invert foods.
Note: Cambarellus shufeldtii can be pretty awkward during feeding. For example, the tubifex worms can get away faster than they can find them.
| I highly recommend reading my article “How to Supplement Shrimp and Snails with Calcium”. |
Related article:
- How to Blanch Cucumbers and Zucchini for Shrimp, Snails, and Fish the Right Way.
- Indian Almond Leaves and Alder Cones in a Shrimp Tank.
- What Do Crayfish Eat?
Features:
- Diet Type: Omnivore
- Feeding Frequency: 3 – 4 times a week
How often should we change the food for Cambarellus shufeldtii?
You can leave their food for 24 hours before removing it. Leaves can be left for several days or even weeks in the tank, Cambarellus shufeldtii will love that.
In spite of their active behavior, it is better to feed them at night (at least in the evening). After all, they are nocturnal animals. Therefore, by doing so, you will replicate the conditions and environment under which they eat naturally.
How Often to Feed Cambarellus Shufeldtii?
Adults can be fed 3 – 4 times a week whereas juveniles Cambarellus shufeldtii should be fed daily.
Obviously, you will have to change it to your livestock’s requirements. Don’t forget that crayfish are scavengers, so when you feed your fish, shrimp, or snails, they will also get their share.
However, do not let them starve or Cambarellus shufeldtii can try to go after shrimp, fry, or even cannibalize.
That is why it is absolutely important that crayfish be fed enough to keep the balance in the tank.
Cambarellus Shufeldtii and Live Plants
In nature, Cambarellus shufeldtii is found in dense aquatic vegetation. However, they are safe to keep with any type of live plant.
Because of their small size, there is little danger. They will not dig up plants (like all bigger crayfish do – Blue crayfish, Red crayfish, Marbled crayfish, Cherax Destructor, etc.), they will not eat plants as well.
This species does not eat healthy plants and can, therefore, be kept in beautifully planted aquariums.
Keeping and Housing Cambarellus Shufeldtii
If you are a first-time crayfish owner it is important that you cycle your tank before bringing any crayfish home. Once the tank is cycled you need to check the quality of the water using a test kit.
Even though Cambarellus shufeldtii are low-maintenance pets and easy to care for, you should always try to replicate their natural environment into their aquarium as closely as possible.
Tank Size and Stocking Density:
This depends on the number of crayfish you are planning to keep. For example, you can put between 5-10 adult Cambarellus shufeldtii in a 10-gallon (40 liters) tank that has lots of covers.
Does it mean that you can put 1 adult crayfish in a 2-gallon tank? Technically yes, but practically no.
Cambarellus shufeldtii are active and need plenty of room to crawl, eat and explore. In addition, you will have to be in constant control over your water parameters. Unfortunately, in small tanks, everything can go wrong very fast.
Therefore, the smallest recommended size for keeping them is 5 gallons (20 liters). If you are going to breed them, you should consider going bigger, just to give them more space for their offspring.
Another thing that you should remember that these crayfish are excellent escape artists and can spend some time out of the water.
So, it will be a good idea to use a lid and make sure the water line in your aquarium is not too high.
Water Parameters:
Temperature: Cambarellus shufeldtii can easily live in a wide range of temperature conditions 18 – 26 °C (64 – 79 °F). However, the optimal temperature in the aquarium should be in the range of 20 – 24 °C (68 – 75 °F). They do not require a heater. Room temperature will suit them absolutely fine.
pH: According to the study, Cambarellus shufeldtii can tolerate a pH range of at least 5.4 – 7.4.
Hardness: Cambarellus shufeldtii will appreciate optimal KH 3 – 15 and GH between 3 – 18 GH.
Filtration:
Considering the tank size, sponge filters are the simplest option (cheap and effective). In addition, Cambarellus shufeldtii will not damage and tear apart the sponge as large crayfish species often do.
They only do so if lots of gunk has accumulated in the sponges and they try to get the gunk inside the sponge by chewing on the sponge.
Note: Basically, you can use any filter that will not allow their young to be sucked up into the filter. So, if you have a canister or hang on the back filter and plant to breed them, the filter intake should be covered with a sponge or net.
Lighting:
As for lighting, they will prefer subdued lighting.
However, if you decide to keep Cambarellus shufeldtii in planted tanks, lighting should be adapted to the needs of plants.
Read more about it in my article “Advanced Guide to Planted Tank Lighting”.
Substrate:
In the aquarium, Cambarellus shufeldtii should be provided with soil and/or sand substrates. It will be an ideal setup for them.
Decorations:
Absolutely yes! You need to give them a lot of places to hide. A LOT! At least 2 places per crayfish.
It can be all types of live plants, artificial plants, leaves, rocks, driftwoods, PVC pipes, bricks, cones, etc. in your tank. They also like spots that are as narrow as possible for themselves to fit in.
Tip: Use large items (like big rocks) throughout the tank so that they have less of a chance of bumping into one another.
This is also crucial for the molting process. Cannibalism after molting can become a problem as well.
Related article:
Regardless of their hardiness, it will be better to acclimate them (read more about it).
Basic Tank Equipment (links to check the price on Amazon)
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Male and Female Difference
Cambarellus shufeldtii are sexually dimorphic. There are a few indicators that give away the gender of the crayfish.
- Abdomen. The female and male of this species can be told apart by looking at the lower part of their abdomen (the lower part of the white section of the underbelly).
The male’s pleopods (the first legs of the swimmerettes) are more rigid. Also, the female has a seminal receptacle.
Males have an extra set of pleopods used for internal fertilization. Therefore, if you see that there is a triangular-ish forming of small legs. That will indicate a male.
Females have seminal receptacles and lack the extra pleopods found behind the walking legs. There will not be that triangular-ish forming of small legs. What you will see is a small nub. That will indicate a female. Females have a wider abdomen.
- Size. Females are a little bit larger than males. They usually reach about 33 mm (1.3 inches) total body length, while male Cambarellus shufeldtii generally range between 15 and 30 mm (up to 1.1 inches) total body length.
- Claws. The female pinchers are shorter and thicker. Male dwarf crayfish have relatively slender and long pinchers.
Related article:
Molting Process
The molting process (or the molt cycle) is the process by which Cambarellus shufeldtii grows. It also allows them to restore lost limbs.
It involves shedding of the exoskeleton and for a short time afterward, the crayfish cannot move until it regains muscle control and the new exoskeleton hardens up.
When they are about to molt they start looking for a place to hide. Otherwise, they can easily fall prey to their tankmates.
Important:
- NEVER disturb your crayfish when they are molting. Do not panic even if you have not seen them for a few days in a row! Give them time. This is the most stressful moment in their
- Keep putting and replacing food in the tank! You never know when they can come up from the molt.
- Keep giving them calcium-rich food.
- Also, do not remove the old exoskeleton from the tank. It contains lots of minerals and your crayfish will eat it later.
You can read more about it in my article “Crayfish and Molting Process.”
Breeding
Cambarellus shufeldtii are very prolific and breed readily.
Mating:
The young Cambarellus shufeldtii grow rapidly, maturing after about 2 months when they reach approximately 18 mm (0.7 inches) in total length.
During its lifespan, the average female produces at least 2 broods of young.
If a female is ready to mate, she will allow a male to approach. After that, the male clamps her claws and puts her on the back. Mating can last from several minutes to an hour or so.
Eggs:
According to the study, reproductive traits of female Cambarellus shufeldtii positively correlate to their body size, number of eggs, and number of juveniles.
Females of this species can usually have anywhere between 15 – 74 (average = 45) eggs.
The females use their appendages to keep the eggs clean from dirt and well oxygenated. Nonetheless, there is high mortality (up to 44%) in egg and early juvenile stages.
Young crayfish:
It usually takes from 3 – 4 weeks to hatch depending on temperature.
After hatching, young crayfish are a little bigger than baby cherry shrimp (about 3 mm). They also grow faster than cherry shrimp.
Young Cambarellus shufeldtii remain with the mother for about 7 – 10 days.
The females usually do not attack their babies. Nonetheless, ideally, you need to isolate them in a separate rearing tank.
Babies can be fed the same thing you feed the adults, it just needs to be in smaller proportions. There is no much cannibalism as long as I do not overcrowd them.
Cambarellus Shufeldtii and Tankmates
Generally, Cambarellus shufeldtii is safe with plants, fish, and shrimp. However, we should not forget that they are opportunistic. Therefore, on occasion, they may get an appetite for one of their tankmates.
It could be due to underfeeding, improper diet, overstocking, or the individual temper.
Fish:
No aggressive, bottom-dwelling, slow-moving, or fish with long fins (like Betta) should be kept in the same tank with Cambarellus shufeldtii.
They do not have the capability to kill most fish, but they may damage fins at night. So, not a good idea to mix them.
People often keep them with small and peaceful fish like Guppies, Neon Tetras, Mollies, Endlers, Dwarf swordtails, etc.
Shrimp:
There are many reports where people kept Cambarellus shufeldtii in shrimp tanks without casualties among the shrimp.
Nonetheless, I take these statements with a grain of salt.
The point is that even if you do not notice crayfish chasing around shrimp, they regularly snap at them when they come too close. Many shrimp in crayfish tanks lose their antennae because of that. The accumulation of such small harassment causes stress to the shrimp.
Therefore, I would not risk putting them with expensive shrimp. Even though shrimp are pretty fast movers with a quick reaction, there is always the chance they can be caught by a crayfish, especially when shrimp molt.
Note: If you still want to keep them together – keep Cambarellus shufeldtii well-fed, it will reduce their potential aggression. Also, make sure that there are enough hiding places for the shrimp and crayfish.
Snails:
Cambarellus shufeldtii usually do not mess with big snails, it takes too much time and energy for that.
However, as with shrimp, they can nip off their antennae periodically.
But baby snails can end up a snack.
Summary of Bad Tank Mates for Cambarellus shufeldtii:
- Larger or aggressive fish.
- Bottom-dwelling, slow-moving, and fish with long fins.
- Any other crayfish species.
- Other freshwater crab species.
- Dwarf frogs.
In Conclusion
Cambarellus shufeldtii is easy to feed and take care of and is a great choice for beginners to the hobby.
They are very nice and active dwarf crayfish. Cambarellus shufeldtii is full of personality and would make a great addition to a planted tank.
I hope this complete care guide can help you decide whether they are the right pet for your tank.
References:
- Elizabeth Hinkle and Neil B. Ford ” Reproductive traits of North American Cajun dwarf crayfish (Cambarellus shufeldtii) from the neches river national wildlife refuge,” The Southwestern Naturalist 65(1), 56-60, (10 May 2021). https://doi.org/10.1894/0038-4909-65.1.56
- Cajun Dwarf Crayfish (Cambarellus shufeldtii). U.S. Fish & Wildlife Service, April 2014
- Adams, S. B. 2012. Cambarellus shufeldtii, version 1.2. USDA Forest Service, Crayfishes of Mississippi website, Oxford, Mississippi.
- Penn, G. H., Jr. 1942. Observations on the biology of the dwarf crayfish, Cambarellus shufeldtii (Faxon). The American Midland Naturalist 28(3):644-647.
- GBIF backbone taxonomy: Cambarellus shufeldtii (Faxon, 1884). Global Biodiversity Information Facility, Copenhagen.
- Distribution and habitat use by dwarf crayfishes (Decapoda: Cambaridae:Cambarellus). Wetlands, Vol.16, № 4, 1996.