Cherax destructor is common in aquaculture and is gaining popularity as an aquarium species. So, if you are thinking of keeping a Cherax destructor crayfish (or Yabby) in your aquarium, you have come to the right place. Below is my complete care guide for Cherax destructor crayfish. It covers all aspects, from natural habitat conditions and how they should be translated within your aquarium, to dietary requirements and how to breed them.
Cherax destructor crayfish are easy to care for as they are very hardy. This species is an opportunistic feeder that can be found in a wide range of habitats and water conditions. In addition, it has an extended breeding period with multiple spawning events, a high spawning frequency, a rapid growth rate and the attainment of maturity.
Cherax is known for its abilities of hibernation and destruction it can cause as it can eat anything and can burry deep in mud or holes when required. When you’re done with this article you’ll find that you’ll be fully grounded in the art of keeping a Yabby.
Important: I want you to be fully aware that Cherax destructor is considered an invasive species.
|The U.S. Fish and Wildlife Service (in 2016 under the Lacey Act (18.U.S.C.42) (USFWS 2016a)) officially listed Cherax destructor as an injurious wildlife species.
As far as I know, It is unlawful to possess, import or sell Cherax destructor in Illinois, Pennsylvania, Ohio, Michigan. For example, the Florida Fish and Wildlife Conservation Commission has listed it as a prohibited species. Check your state laws before purchasing. NEVER release Cherax destructor into the wild!
Quick Notes about Cherax Destructor
|Common Names||Yabby, Blue Claw Fresh water, Blue Pearl|
|Scientific Name||Cherax destructor|
|Tank size (minimum)||30 gallons (~120 liters)|
|Size||10 – 20 cm (4 – 8 inches)|
|Optimal Temperature||25 – 28 C (77– 82 F)|
|Optimal PH||7.5 – 8.5 (7.0 – 9.0)|
|Optimal GH||6 – 12 (3 – 22)|
|Optimal KH||4 – 6 (2 – 18)|
|Optimal TDS||150 – 300 (100 – 1000)|
|Nitrate||Less than 20ppm|
|Life span||up to 6 – 8 year|
|Color Form||Different color variations: green-beige, black, blue, dirty-white, light pink, orange, and light brown.|
Interesting fact: The term “Yabby” seems to derive from the word “Yabij “in the aboriginal language, which was used by wandering tribes to describe the native crayfish from central Australia. The generic name Cherax is thought to be a misspelling of the Greek word ‘charax’, meaning a pointed stake.”
Origins, Natural Habitat of the Cherax Destructor
This crustacean’s natural habitat is Southern Australia. They are commonly found on muddy or silted bottoms of streams, swamps, reservoirs, and rivers. Cherax destructors are rarely found in clear water habitats; they seem to prefer water with moderate levels of turbidity.
This species can also survive for long periods in areas where a body of water has dried up by lying dormant in burrows in the mud.
Description of the Cherax Destructor
Their eyes are not their best sense, the senses of touch and taste are far more important, and are perceived using a pair of large feelers (or antennae) and a pair of small, fine, centrally located feelers (or antennules).
The color of the Cherax destructor is highly variable and includes green-beige, black, blue, dirty-white, light pink, and orange forms in addition to the more common light brown.
The type that is bred for the aquarium trade is often bright blue. Their specific coloration can vary widely depending on water conditions, season, diet, environment and genes.
Yabbies grow pretty big and range from 10-20 cm in length about 4-8 inches. Most Cherax destructor can grow from juvenile to over 15cm (5.9″) in time as little as 12 months. Fully grown, they can weigh up to 350g.
Cherax destructor has a relatively long life span (from 3 to 6 years), compared to other crayfish species. However, there are also reports that some individuals lived up to 8 years.
The Behavior of the Cherax Destructor
Cherax destructors can be great aquarium pets if you understand their natural tendencies and behaviors and care for them accordingly.
First of all, they are extremely efficient diggers. Actually, this is why it got the name “Destructor” – because of the damage, it can cause to dam walls and levee banks after burrowing. It buries itself 0.5-2 m deep in the mud or the holes and able to survive several months in the burrows.
Cherax destructor is a nocturnal species. Feeding behavior is mostly controlled by the amount of light filtering through the water and it is often found that the greatest periods of activity occur shortly before dawn and just after dusk.
These crayfish are very aggressive and territorial with their own species.
Cherax Destructor Molting
The Cherax destructor needs to shed its exoskeleton to grow, so be sure not to confuse this for a deceased yabby. Also, take care not to discard the exoskeleton as the yabby may will it to recycle the calcium and other minerals.
The frequency of molt depends on age and temperature. Baby Cherax destructors can molt every 5 – 7 days, juvenile yabbies usually molt every 3 to 4 weeks and the length of time between molts will increase as the crayfish gets older. Adult yabbies only molt 1 or 2 times a year.
Most metabolic activities are reduced during the pre-molting process. So, if you see that your crayfish does not eat as it used to – this can be the sign of molting.
After removal of the old shell, Cherax destructors will need a place to hide till it’s new shell has hardened. Keep in mind that freshly molted crayfish are exhausted, stressed and vulnerable to predation due to the lack of protective covering.
After molting, the metabolic demand (to harden the shell) for calcium is particularly great. Crayfish use calcium to produce a new and healthy shell. I highly recommend reading my article “How to Supplement Shrimp and Snails with Calcium”. These nutrients are necessary in abundance especially following the molting of your crayfish.
Is Cherax Destructor Plant Safe?
No, Cherax destructor is not plant safe. It is absolutely not possible to keep them in planted aquariums. They will eat, cut, shred and uproot everything if it is possible. They are lawnmowers.
Note: Only floating plants can be relatively safe with the Cherax destructor.
Note #2: If you need a plant safe crayfish, check out my guide “Dwarf Mexican Crayfish – Detailed Guide: Care, Diet, and Breeding”.
Feeding Cherax Destructor
Cherax destructor is an opportunistic and omnivorous feeder. Although plant material and detritus often dominate the gut contents, it will eat anything it comes across. Their diet includes plants, algae, animal detritus, macrophytes, dead and live animals such as snails, fish frogs, insects, tadpoles, fingerlings, etc.
According to different studies, in the wild, Cherax destructor species has the ability to switch food preferences. For example, when high protein food sources (fish, snails, etc.) become limited they easily switch to a predominantly herbaceous/detrital diet.
They will act as a scavenger in the aquarium, eating any food that comes to rest on the bottom. So you can decide to add quality sinking pellet and meaty food such as fish fillets to their regiment. They can eat any kind of leaves and other plants that they will find in the water.
Within the aquarium Cherax destructor can be fed a variety of foods:
- Vegetables (Boiled lettuce, cabbage, zucchini, carrots, etc. is a popular choice for feeding your new friends).
- Crustaceans pellets (These pellets are specially formulated to contain the full spectrum of nutrients for your pet crayfish. For example,Hikari Shrimp Cuisine, Hikari Micro Wafers, and Hikari Tropical Crab Cuisine (link to check the price on Amazon) can be a good option to go for if you want to maintain or improve that coloration of your crayfish.
- Fish or shrimp algae pellets, flakes, etc. (Cherax destructor crayfish are not picky. They will eat whatever you give them).
- Almond leaves (They help the molting process and have medicinal properties).
- Plants (You can buy cheap plants for that).
Ensure that the diet of your pet crayfish is rich in nutrients, especially calcium. A lack of calcium in the water results in soft-shelled yabbies.
Important: You must take note not to overfeed your yabby. They possess a small stomach and will stop eating when full, leaving the remainder of the food. It’s also not necessary to feed them every day. You can adapt the routine of feeding them two small pieces of food every two to three days. For a healthy habitat for them try to clear away any left-over food for two hours.
Keeping and Housing Cherax Destructor
Cherax destructors are usually straight forward and easy to care for. However, for optimal results, here are some handy tips that you should follow in order to keep Yabbies in an aquarium.
The first thing you should consider when setting up a tank for the Cherax destructor is the size of the tank.
In my opinion, the absolute minimum tank size for an adult crayfish is a 30 or 40-gallon tank (~160 liters). You must also put special consideration toward the length of the tank.
You might need a bigger tank if housing more than one yabby, though housing multiple males together is not recommended. They need a lot of space with places to hide from the other crayfish. Remember that Yabbies are very territorial and they will fight.
Tip: The yabbies tend to become good escape artists and will climb air hoses and silicon sealant because of this, you should place a fitted lid on the tank.
This species of crayfish is known as one the hardiest of all of them. This is because it can tolerate poor water conditions and long periods of drought by burrowing deep into river beds or dam walls to stay moist. In addition, according to U.S. Fish & Wildlife Service, Cherax destructor tolerates high salinities, with growth ceasing at 8 ppt (approximately equal to 25% seawater) and mortalities starting to occur at 16 ppt.
However, we are here not to test their limits but provide the best care possible.
Cherax destructor prefers to live in alkaline and nonchlorinated waters with a pH between 7.5 and 8.5. However, yabbies can tolerate a pH of 7.0 and 9.0; a pH of below 7.0 increases the toxicity of dissolved metals within the water column and makes the exoskeleton softer, and a pH of above 9.0 greatly increases the toxicity of ammonia.
The optimum temperature range for the growth of Cherax destructor suggested by this experiment is from 25 to 28°C (77 – 82 F).
Interesting facts: They can live in a wide range of water temperatures ranging from 1 to 35 C (33 – 95 F). However, they fall into a state of partial hibernation at temperatures below 15 C (59 F) as their metabolism and feeding all but stop. Cherax destructor also stops growing at 34 C (93 F) and mortalities start to occur at 36°C (97 F).
Substrate and Decorations
They might not burrow much unless the water quality is poor, but they will dig out under rocks and enlarge holes where possible. Ideally, you should create a 5 – 10 cm (2 – 4 inches) layer of sand, soil or fine gravel to allow burrowing.
In most of my guides about shrimp, snails, and small crabs, I usually recommend having sponge filters. They are cheap and provide everything that these animals need. However, having sponge filters with Cherax destructor is just a very bad idea. The point is that they like to chip and chew on it. With time, they will simply shred and break apart the sponge. Therefore, we have only two options here – Hang on the back and Canister filters.
Important: Do not put it in an uncycled tank. Although they are pretty hardy and potentially can survive even during cycling, you do not want to take your chances.
Note: Do not forget about using the water conditioners each time the water is changed.
Decorations and Hiding Places
Provide them with lots of places to hide or your Yabbies burrow and dig even more often than usual. They just need places to hide out! Crayfish naturally like to have some shelter and safety be it from hollow structures, rocks, driftwood or plants.
Air is a must necessity to any living beings. In order for Yabbies to grow well, continuous aeration is required to maintain the level of oxygen in the water. Try and make the water properly aerated by using the proper equipment.
Regardless of their hardiness, it will be better to acclimate them (read more about it here) as all invertebrates.
Tank Equipment (links to check the price on Amazon)
Identifying and Sexing Cherax Destructor
- The larger yabbies are males. Their claws grow faster than the rest of the body, reaching the weight of 100 g in large males (it is almost 1/3 of their total weight!).
- According to the goverment report, Male yabbies also grow 68% faster than female yabbies. Females grow at the same rate as males until sexual maturity at about 20 g, after which, relative to males, female growth slows markedly.
- The male yabby’s reproductive papillae which are short projections are found at the base of the last pair (the fifth) of walking legs. While openings on the bases of the third-last pair of legs can be found on the females.
Mating Cherax Destructor
If you are trying to breed yabbies, it is fairly easy and is usually achieved through simple co-habitation of the tank.
Cherax destructor females become sexually mature when they are about 1 year old and approximately 6 – 10 cm (2 – 4 inches) in total length.
The male yabby will flip over the female and deposit a sperm packet near the female’s reproductive organs. Next, the females produce eggs that will cross through the sperm packet, fertilizing them.
Breeding Cherax Destructor
Cherax destructor females keep fertilized eggs at the underside of the tail until they hatch 8 – 10 weeks later. Berried females use their pleopods to keep eggs cleaned and well oxygenated.
The eggs are approximately 2 mm in length and oval in shape, they are usually olive green in color.
The average clutch size is 350 – 450 eggs. Female fecundity increases with body size, reaching up to more than 1000 for a large female.
The eggs are normally incubated within a time span of 19 and 40 days depending upon temperature. For example, in water temperatures of 20°C (68F), the eggs hatch within 40 days. As temperature increases, the length of time taken to hatch decreases until water temperatures reach 30°C; temperatures above 30°C adversely affect hatching.
Rearing baby Cherax Destructor
The species has a high parental care of their young. After hatching, newly hatched Cherax destructor babies are still attached to pleopods (swimmerets) on the female’s abdomen. She will carry the young and release them when they reach stage 3 juveniles. In newly hatched yabbies, molting may take place every 4 – 5 days.
Note: When the young leave the mother, the female Cherax destructor can mate again because her ovaries are held almost in a constant state of readiness.
Once the babies leave their mother, you will need to transfer them into a separate tank with lots of hiding places. It will help you to prevent any aggression from her side.
Note: Of course, you can also separate the berried female from the main tank and then put her back.
Tiny Cherax destructor will need a lot of protein to grow and in the absence of food can start cannibalizing fast. The results of the experiments show that maximum growth can be achieved in the 35% protein diet.
Cherax Destructor and Suitable Tankmates
While they are small, Cherax destructor can co-exist with other aquatic inhabitants. However, in time they start to actively hunt most tank mates including fish, crustacea and snails.
Cherax Destructor and Fish
You should know that yabbies are bottom dwellers and will eat anything they can catch. So because of these, you shouldn’t keep them in the same aquarium with small fish (especially bottom-dwelling fish) as these are easy prey at night time for this species.
They will eat any passing fish they can catch. So it’s advisable to place only one species in a tank.
Cherax Destructor and Snails
Cherax Destructor and Shrimp
If you are ready to lose shrimp from time to time, you can keep them with cheap species like Cherry shrimp.
In general, I would not advise keeping Cherax destructor and dwarf shrimp together, especially with Bamboo shrimp and Vampire shrimp. Due to the unique food intake technique (these shrimp stay motionless), they can be an easy target for the crayfish.
Cherax Destructor and Crayfish
Cherax destructor is also cannibalistic, particularly in overcrowded situations or if there is insufficient natural food available. Animals that have recently molted are more susceptible to being cannibalized.
Therefore, it can be risky to house multiple crayfish in the same tank. Males, in particular, are extremely likely to fight and eventually kill one another when housed together. Multiple Cherax destructor should be kept only in groups of one male with one female.
Cherax Destructor and Frogs
Do not keep Cherax destructor and frogs together. They will hunt them down and eat them. According to the New South Wales Government (Threatened Species Conservation. Act 1995), there are 29 endangered frog species because of the Cherax destructor.
Cherax Destructor and Tortoise
Do not keep Cherax destructor and tortoise together. Yabbies also showed strongly aggressive and predatory behavior towards tortoise hatchlings in a laboratory study.
My Cherax destructor Lost Limbs, claws, etc…
Do not worry. Yabbies like most crayfish possess the ability to regenerate lost limbs, a handy trick considering limbs and claws are often lost during fights with other crustaceans.
These lost body parts start to grow back at the next molt, however, total regeneration is not immediate and may take several molts to complete. The process of regeneration goes slower as the yabbies grow in age.
Cherax destructor is very easy to care for due to the high fecundity, quick growth rate, feeding habits and extreme tolerance of the species. It can be a great addition to the aquariums of both beginners and experienced aquarists (if this species is not prohibited by your state law).
- S. Fish and Wildlife Service. (2014, September). Ecological Risk Screening Summary.
- Combined Effects of Temperature and Diet on Growth and Survival of Young-of-Year Crayfish: A Comparison between Indigenous and Invasive Species Annalisa Paglianti,Francesca Gherardi. Journal of Crustacean Biology, Volume 24, Issue 1, 1 January 2004, Pages 140–148,
- Effect of Temperature on Molt Increment and Intermolt Period of a Juvenile Australian Fresh-Water Crayfish, Cherax destructor. G. D. Verhoef, C. M. Austin, P. L. Jones and F. Stagnitti.Journal of Crustacean Biology. 18, No. 4 (Nov., 1998), pp. 673-679. DOI: 10.2307/1549142
- S. Fish& Wildlife Service, September 2012. Ecological Risk Screening Summary. Revised, September 2014, February 2019. Web Version, 7/12/2019
- Growth and survival of Cherax destructor and Bidyanus bidyanus stocked in a communal aquarium system. Article. January 2015
- Multimodal individual recognition in the crayfish Cherax Destructor. Article in Marine and Freshwater Behaviour and Physiology. December 2004. DOI: 10.1080/10236240400016595
- Evidence for the Inheritance of a Blue Variant of the Australian Fresh-Water Crayfish Cherax Destructor(Decapoda: Parastacidae) as an Autosomal Recessive. L. Walker,C. M. Austin, M. Meewan. Journal of Crustacean Biology, Volume 20, Issue 1, 1 January 2000, Pages 25–30,
- The Bioenergetics of the juvenile Yabbie (Cherax destructor Clark). Richard Musgrove M.Sc. Hons. Zoology Department University of Adelaide South Australia
- Final report, FRDC Project 94/075 : enhancement of yabby production from Western Australian farm dams / principal investigator, Craig Lawrence. Perth , W.A. : Fisheries Western Australia, 1998 viii, 134 p