Cherax quadricarinatus (redclaw crayfish)
- Summary of Invasiveness
- Taxonomic Tree
- Notes on Taxonomy and Nomenclature
- Distribution Table
- History of Introduction and Spread
- Risk of Introduction
- Habitat List
- Biology and Ecology
- Natural Food Sources
- Air Temperature
- Water Tolerances
- Natural enemies
- Notes on Natural Enemies
- Means of Movement and Dispersal
- Pathway Causes
- Pathway Vectors
- Impact Summary
- Economic Impact
- Environmental Impact
- Impact: Biodiversity
- Social Impact
- Risk and Impact Factors
- Uses List
- Similarities to Other Species/Conditions
- Prevention and Control
- Gaps in Knowledge/Research Needs
- Links to Websites
- Distribution Maps
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PicturesTop of page
IdentityTop of page
Preferred Scientific Name
- Cherax quadricarinatus (von Martens, 1868)
Preferred Common Name
- redclaw crayfish
Other Scientific Names
- Astacus quadricarinatus von Martens, 1868
- Chaeraps quadricarinatus (von Martens, 1868)
- Cheraps quadricarinatus (von Martens, 1868)
International Common Names
- English: Australian crawfish; Australian red claw crayfish; freshwater blueclaw crayfish; freshwater crayfish; North Queensland yabby; Queensland redclaw; red claw; red claw crayfish; redclaw; tropical blue crayfish
Local Common Names
- Australia: beekodl; elparra; juin-ju; junju; laamballay; mintoola; ndaag; piccool; Queensland marron; red claw crayfish; red claw marron; ruja; yandurrer
- France: ecrevisse Australienne; ecrevisse redclaw du Queensland
- Netherlands: Australische kreeft; roodschaarkreeft
- USA: Australian crawfish
Summary of InvasivenessTop of page
C. quadricarinatus is an aquatic crayfish, naturally distributed in a wide variety of habitats in its native range of distribution (Queensland and Northern Territory in Australia and southeastern Papua New Guinea). Due to the harsh physical conditions it has adapted to in its native range, C. quadricarinatus has a robust nature with broad tolerances to environmental extremes. Such environmental tolerance, combined with its rapid growth rate and relatively large dimensions, makes it an ideal species for aquaculture and aquarium trade.
In Australia, the commercial interest in this species began in the late 1980s, when it was introduced to Western Australia and New South Wales. Starting from the 1990s, many countries in southern Asia (including China), North and South America, New Caledonia, Africa, Israel and parts of Europe obtained permits to import broodstock and juveniles. Established, feral populations are reported in Ecuador, Israel, Mexico, Jamaica, Paraguay, Puerto Rico, Singapore, South Africa, Thailand, and Zambia.
No studies have investigated the invasive potential of C. quadricarinatus and the negative impact it may exert on the invaded ecosystems. Concerns are raised about its potential to outcompete indigenous crustaceans and other components of the invaded communities. It may be also a vector of parasites and diseases.
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Metazoa
- Phylum: Arthropoda
- Subphylum: Crustacea
- Class: Malacostraca
- Subclass: Eumalacostraca
- Order: Decapoda
- Suborder: Reptantia
- Unknown: Parastacoidea
- Family: Parastacidae
- Genus: Cherax
- Species: Cherax quadricarinatus
Notes on Taxonomy and NomenclatureTop of page
The taxonomic status of Cherax quadricarinatus is accepted. No subspecies have been proposed, but different “strains” have been distinguished.
Macaranas et al. (1995) analyzed the genetic structure of 12 populations from the Northern Territory and North Queensland by the use of allozymes and RAPD (randomly amplified polymorphic DNA) markers. Electrophoretic analysis of 28 enzyme loci revealed generally low estimates of heterozygosity within each population and low estimates of genetic differentiation among populations except for a fixed allelic difference at the carbonic anhydrase locus between populations of the two areas. The authors explained the low levels of genetic variability among the populations from North Queensland as a reflection of their recent radiation across the Gulf of Carpentaria after its inundation between 18000 and 6000 BP. On the contrary, RAPD analysis of 7 populations distinguished each of them and even grouped them according to geographic proximity. RAPD analyses also revealed significant genetic variability both within the species and within individual populations. The authors conclude by noting that RAPD fragments are useful for differentiating redclaw strains and constitute a marking system that could be used in crayfish genetic improvement programs.
The generic name Cherax is thought to be a misspelling of the Greek word 'charax', meaning a pointed stake, i.e. a thing that scratches.
DescriptionTop of page
An accurate description of C. quadricarinatus is provided by Souty-Grosset et al. (2006), as follows:
Body: carapace smooth with one pair of long post-orbital ridges forming two keels on anterior carapace; spines on shoulder of carapace behind cervical groove - one prominent. Dorsal surface of telson without spines, membranous over posterior half.
Rostrum: long with prominent apex; proximal borders more or less parallel, raised and extending posteriorly as two keels; three pairs of short lateral spines; median carina absent.
Appendages: chelipeds can be very long in adult males.
Chelae smooth, straight with narrow cutting edges; inner margin of chelae propodus longer than dactylus; distal superior margin of propodus uncalcified in mature males and forming a bright red-orange patch (hence common English name); mat of setae along proximal cutting edges of chelae absent. Distinct spur on inferior margin of cheliped coxa. Base of antenna with a distinct prominent spine. Antennae may be longer than the total body length in adult males.
Length: up to 35 cm of total length, seldom longer.
Colour: blue, mottled with beige and red on joints and body, red patches laterally on abdominal segments.
A morphometric analysis was done by Gu et al. (1994). A rapid increase in the relative growth of chela width and cheliped length was recorded in males with a carapace length of 43 and 45 mm, respectively. Males larger than this size had wider chelae and longer chelipeds than females with a similar carapace length. In males with a carapace length shorter <42 mm, the ratio of abdomen width to carapace width increased with carapace length while it decreased in those with a carapace length ≥42 mm. In females with a carapace length <49 mm, the ratio increased with carapace length while it was constant in those with a carapace length ≥49 mm. The percentage of muscle to body weight varied with carapace length, being the highest (34%) in crayfish with a carapace length of 74 mm.
The red patch located on the propodus of C. quadricarinatus males has attracted much attention, being a sexually dimorphic structure. According to Karplus et al. (2003), this patch presents an enigma because it is soft and uncalcified, consisting of a thin red to whitish-orange membrane. It presents an impairment of the fighting capability of the males, which, like many other clawed crustaceans, use these appendages in intra- and interspecific aggressive interactions. A hypothesis is that the red patch transmits information concerning the gender, size and quality of its owner.
DistributionTop of page
The distribution of this species is restricted to tropical and subtropical climates (Semple et al., 1995). C. quadricarinatus is indigenous to the rivers of northwestern Queensland and of the northern and eastern parts of Northern Territory in Australia (Riek, 1969; Curtis and Jones, 1995), and to the catchments of southeastern Papua New Guinea (Holthuis, 1986). The species remained unknown to the rest of Australia until the late 1980s, when interest in its aquaculture began (Lawrence and Jones, 2002). In that period, notwithstanding that C. quadricarinatus was classed as a restricted species for importation into Western Australia (Anonymous, 1997), it was permitted to assess, under quarantine, the potential for aquaculture in the Ord Valley in the East Kimberley of the ‘Walkamin’ strain (Doupé et al., 2004). Subsequently, a limited number of aquaculture licenses were issued, but shortly after feral populations of redclaw were found established in Lake Kununurra, a Ramsar wetland formed through impoundment of the Ord River within the Kimberley Drainage Division of Western Australia (Morgan et al., 2004). However, redclaw used in Ord River aquaculture are a genetically different strain compared to those now found in Lake Kununurra, indicating another source of introduction. As suggested by Doupé et al. (2004), the feral populations may be the result of illegal translocations by recreational fishermen. The redclaw has subsequently spread downstream from Lake Kununurra into the lower Ord River, where local recreational anglers have reported redclaw in the stomachs of barramundi (Lates calcarifer) and catfish (Arius spp.). Introduced feral populations of C. quadricarinatus are also to be found in lake systems in northern and southeastern Queensland (Lynas et al., 2007). Recently, individuals have been found in the wild in New South Wales, prompting a discussion as to whether they would be a threat to indigenous crayfish species (Lynas et al., 2007).
From Australia, the species has been exported to many other countries with subtropical to tropical climates where commercial production has been attempted. Many countries in southern Asia (including China), North and South America, New Caledonia, Africa, Israel and parts of Europe have obtained C. quadricarinatus stock throughout the 1990s. An application to import them into Norway for aquacultural purposes was refused. In some of the countries of introduction, for example in the USA, no wild populations of C. quadricarinatus have as yet been reported (Lodge et al., 2000). In other countries, for example the People’s Republic of China, no information is available. On the contrary, there are reports of established feral populations in Ecuador, Israel, Mexico, Jamaica, Paraguay, Puerto Rico, Singapore, South Africa, Thailand, and Zambia (Romero, 1997, 2002; Williams et al., 2001; Moor, 2002; Zimmerman, 2003; Ahyong and Yeo, 2007; Bortolini et al., 2007; Garcia Vazquez, 2009). Details of C. quadricarinatus’ introduction to Israel, Mexico, and Singapore are reported in ‘History of Introduction and Spread’.
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.Last updated: 10 Feb 2022
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Reference||Notes|
|Eswatini||Present||Introduced||First reported: Late 1990s|
|Mauritius||Present||Introduced||First reported: 1980s|
|Morocco||Present, Only in captivity/cultivation||Introduced||R. Richard, commercial farmer/consultant, Australia, pers. comm. 2004|
|South Africa||Present||Introduced||First reported: 1980s|
|Zambia||Present||Introduced||1992||From South Africa|
|China||Present||Introduced||First reported: 1980s|
|Indonesia||Present, Only in captivity/cultivation||Introduced||F. Ambadar, commercial redclaw farmer, Indonesia, pers. comm. 2004|
|Israel||Present, Few occurrences||2011||Introduced||Introduced from the USA in the early 1990s by the Dept. of Fisheries, Ministry of Agriculture; experimentation was carried out at the Agricultural Research Organization at Bet Dagan and the Aquacultural Research Station, Ministry of Agriculture, Dor; in 1994, individuals were discovered to have overwintered in open earthen ponds; raised in Kfar Monash; a large specimen was found in the Sea of Galilee in 2011|
|Philippines||Present, Only in captivity/cultivation||Introduced||D. Jerry, James Cook University, Australia, pers. comm. 2004|
|Greece||Present||Introduced||In aquaria of restaurants|
|Italy||Present, Only in captivity/cultivation||Introduced||1985||Farmed|
|Spain||Present, Only in captivity/cultivation||Introduced|
|Jamaica||Present, Widespread||1999||Introduced||1993||Broodstock had been introduced to Jamaica in 1993 and feral populations were recorded in the Black River in 1999|
|Mexico||Present, Localized||2000||Introduced||Imported by the Universidad Autonoma Metropolitana, Mexico City in 1995; started to be farmed in 2000 in a facility in central Morelos; recorded in the adjacent recreational aquatic park in 2000|
|Puerto Rico||Present, Widespread||1998||Introduced||1997||Introduced illegally in 1997 and spread into the wild in 1998|
|-California||Present, Only in captivity/cultivation||Introduced|
|Australia||Present||Present based on regional distribution.|
|-New South Wales||Present||Introduced|
|Papua New Guinea||Present||Native|
|Samoa||Present, Only in captivity/cultivation||Introduced||L. Bell, Samoa, pers. comm., 2004|
|Argentina||Present, Only in captivity/cultivation||Introduced|
|Paraguay||Present||Introduced||1991||Established, from Australia|
|Uruguay||Present, Only in captivity/cultivation||Introduced||J-L. Bertolotto, commercial redclaw farmer, Uruguay, pers. comm., 2004|
History of Introduction and SpreadTop of page
C. quadricarinatus was introduced to Israel from the USA in the early 1990s by the Department of Fisheries, Ministry of Agriculture, for aquaculture purposes (FAO-DIAS, 2011). Experimental stocking and growout studies were carried out at the Agricultural Research Organization at Bet Dagan and the Aquacultural Research Station, Ministry of Agriculture, Dor (Karplus et al., 1995, 1998; Sagi et al., 1998). In the latter location, in 1994, individuals were discovered to have overwintered in open earthen ponds. Moreover, it was recorded that “in the absence of fences” individuals wandered into adjacent ponds and drainage canals. Karplus et al. (1998) opined that the species is able to survive, disperse and establish in Israel. He considered that “introduction of C. quadricarinatus into Israel’s southern part, in which the introduction sites are isolated from natural water sources by the desert, seems safer” and cautioned against introducing it into the temperate areas. As noted by Snovsky and Galil (2011), Karplus’ advice went unheeded, the species is now raised in Kfar Monash, on the central coastal plain, where intensive farming is able to provide up to 100,000,000 juveniles to distributors and ornamental shop chains in Israel and Europe (http://www.aquology.com). On January 2011, a large specimen was captured in shallow waters (2-3 m depth) at the Sea of Galilee (Lake Tiberias), opposite Tiberias promenade and bathing beach (Snovsky and Galil, 2011).
In Mexico, the redclaw crayfish have been introduced a number of times to establish commercial cultures and several ventures have been producing moderate amounts for the local markets in at least the states of Colima, Distrito Federal, Morelos, Jalisco, Tamaulipas, and Yucatan (Bortolini et al., 2007). The first importation of redclaw crayfish into Mexico occurred in 1995 when the Experimental Aquaculture Plant of the Universidad Autónoma Metropolitana, in Mexico City, brought a small stock to initiate a research program to determine its suitability to be cultured in Mexico (Ponce-Palafox et al., 1999). In 1998, organisms were transferred to several research centers in Ensenada, Baja California; La Paz, Baja California Sur; and Mérida, Yucatan, plus to an aquaculture center in the state of Morelos; since then several other research centers and universities around Mexico have started research projects using this species. Feral established populations of C. quadricarinatus were reported in the states of Morelos and Tamaulipas in 2005. In Morelos, C. quadricarinatus is apparently contained inside an aquatic park reaching very high densities, probably taking advantage of food remains left by park visitors and a controlled environment where no fishing is allowed (Bortolini et al., 2007). In Tamaulipas, the population is widely spread over an area 65-km long within a network of irrigation canals connected to the Guayalejo and Sabinas rivers (Bortolini et al., 2007).
In Singapore, since 2000 sampling and observations in several water catchment reservoirs have revealed the presence of C. quadricarinatus. Crayfish were recorded from at least three of Singapore’s major reservoirs, namely Kranji, Lower Peirce and Upper Seletar (Ahyong and Yeo, 2007). C. quadricarinatus is likely to be a recent introduction, probably becoming feral some time between late 1990s and early 2000s. It is not presently cultured for human consumption, but in the last decade it has become popular in the aquarium trade. As such, feral populations probably derive from accidental or deliberate releases. Multiple independent releases or escapes of C. quadricarinatus have probably occurred.
In Europe, it has been generally considered that this tropical species would not become established if it escaped into the wild. For this reason, it is the only crayfish from outside Europe that can be imported alive into Britain (Holdich et al., 1999). On the contrary, since it has the potential to survive low winter temperatures, there is the risk that it will become established, particularly in southern European countries. Its introduction and its culture in England and Spain are mainly purposed to the aquarist trade. Currently, only Italy is involved in culturing redclaws for food. Recently, Koutrakis et al. (2007) reported the presence of C. quadricarinatus in restaurant’s aquaria in the city of Igoumenitsa, Epirus, Greece, and the availability of the species to the aquarium hobbyists (Perdikaris et al., 2005).
C. quadricarinatus has been assessed by IUCN (2010) as Least Concern. There are no major threats impacting this species or its habitat, and it is unlikely to be experiencing significant population declines.
IntroductionsTop of page
|Introduced to||Introduced from||Year||Reason||Introduced by||Established in wild through||References||Notes|
|Natural reproduction||Continuous restocking|
|China||Australia||1990||Aquaculture (pathway cause)||Private sector||No||No||Ackefors (2000)|
|Ecuador||Australia||1994||Aquaculture (pathway cause)||Private sector||Yes||No||Romero (1997); Romero (2002)|
|Israel||USA||1991||Yes||No||Snovsky and Galil (2011)|
|Malaysia||Australia||Aquaculture (pathway cause)||Private sector||No||No||Chang (2001)|
|Mexico||1995||Yes||No||Bortolini et al. (2007)|
|Puerto Rico||1997||Yes||No||Garcia Vazquez (2009); Williams et al. (2001)|
|Singapore||1990s-2000s||Aquarium trade (pathway cause)||Yes||No||Ahyong and Yeo (2007)|
|Thailand||Australia||Aquaculture (pathway cause)||Private sector||No||No||Chang (2001)|
|USA||Australia||1990||Aquaculture (pathway cause); Research (pathway cause)||Private sector||No||No||Medley et al. (1994)|
|Western Australia||1980s||Aquaculture (pathway cause)||Yes||No||Lynas et al. (2007)|
|Zambia||South Africa||1992||Yes||No||FAO-DIAS (2011)|
Risk of IntroductionTop of page
C. quadricarinatus has a considerable potential for commercial culture. High growth rates and tolerance to wide variations in water quality make the species suitable for cultivation (Anson and Rouse, 1994), although the industry has developed relatively slowly in Australia and elsewhere in the world (Lawrence and Jones, 2002). Besides, the hardiness and conspicuous colouration of this species has also made it popular in the aquarium trade worldwide (Ahyong and Yeo, 2007). There is also the belief that, being a tropical species, C. quadricarinatus would not become established in temperate countries if it escaped into the wild. On the contrary, since it has the potential to survive low winter temperatures, there is the risk that it will become established, particularly in Mediterranean countries (e.g. Greece, Israel, Italy, Morocco, and Spain), in which much interest is being directed to its cultivation. The risk increases with the prospect of global warming.
HabitatTop of page
C. quadricarinatus is a non-burrowing species that is tolerant of a wide variety of habitats, from fast flowing rivers and coastal streams to slower moving upper reaches of rivers, lakes, lagoons, and billabongs (Wingfield, 2002). However, redclaw seem to prefer rocky habitats with plenty of caves for exploring and foraging, as well as for protection during moulting (Souty-Grosset et al., 2006). Billabongs are frequently highly eutrophic with poor water quality, and progressively diminish in size as the water evaporates. Crayfish are thus confined in a few remaining water pools, in which they coexist until the rainy season, showing a gregarious habit which is unusual for crayfish species.
Habitat ListTop of page
|Terrestrial||Natural / Semi-natural||Wetlands||Present, no further details||Natural|
|Freshwater||Irrigation channels||Present, no further details||Natural|
|Freshwater||Irrigation channels||Present, no further details||Productive/non-natural|
|Freshwater||Lakes||Present, no further details||Natural|
|Freshwater||Reservoirs||Present, no further details||Natural|
|Freshwater||Reservoirs||Present, no further details||Productive/non-natural|
|Freshwater||Rivers / streams||Present, no further details||Natural|
|Freshwater||Ponds||Present, no further details||Natural|
|Freshwater||Ponds||Present, no further details||Productive/non-natural|
|Brackish||Lagoons||Present, no further details||Natural|
Biology and EcologyTop of page
Apart from Macaranas et als (1995) study on the genetic structure of some populations, a recent study has focused on the genetic basis of intersex individuals.
Parnes et al. (2003) tested a sex-determination model for C. quadricarinatus in which intersex individuals (functionally males) were assumed to be females from a genetic viewpoint (WZ). Individual crosses were performed between intersex and female crayfish, with control crosses being performed between normal males and females. The control crosses yielded, in most cases, the expected 1:1 sex ratio in the F1 progeny. Crosses between intersex individuals and females yielded a 1:3 (male: female) sex ratio in most crosses. According to the hypothesis, one-third of the females produced in a cross of a female with an intersex animal should be WW females. The hypothesis was tested by crossing normal males with F1 females, which were progeny of intersex fathers. These crosses yielded almost 100% females, a finding that conforms to the above-suggested sex determination model for C. quadricarinatus and the female WZ genotype of intersex individuals.
The molecular diversity in wild stocks of this species in Australia and Papua New Guinea has been studied by Baker et al. (2008).
The studies available on C. quadricarinatus’ reproductive biology have been mainly purposed to optimize production of farmed crayfish. For example, King (1993) showed that sexually mature C. quadricarinatus kept at 25°C with a 12L:12D photoperiod spawned all year. Females could spawn twice, and possibly three times, between annual moults, although not all females mated or exhibited multiple spawning.
Yeh and Rouse (1995) investigated the effects of water temperature on C. quadricarinatus’ spawning rate, showing its increase with temperature, with 30°C providing the highest spawning rate. No difference was on the contrary found among stocking densities of 10, 15 and 20 m-2 or among sex ratios of 1:1, 1:3, and 1:5 M:F. A combination of density of 20 m-2, sex ratio of 1:5 M:F, high temperature and long day lengths (14L:10D) were effective to increase spawning rates, but these conditions cannot be maintained for more than 3 months.
Barki et al. (1997) compared annual spawning and moulting in laboratory crayfish groups at a sex ratio of 1:4 M:F under a constant temperature (26–28°C) and either an ambient or a controlled (14L:10D) photoperiod. A similar annual pattern of spawning and molting was evident under the two photoperiod regimes. Females spawned three times and moulted twice a year on average. Most spawning occurred during spring and summer, and moulting occurred mainly after the breeding season but also between spawns.
Information that can be applied also to feral populations are as follows:
Male and female redclaw can be easily distinguished by the presence of the red patch on the chelae of males. Life span is 4-5 years based on maximum size recorded of around 650 g. Sexual maturity is reached at 6-12 months with a body weight of approximately 110-120 g. Male specimens are fully grown at two years when they reach the weight of about 400 g. In Queensland, redclaw usually mature at around 6 months of age (45-50 g), but in farms it is possible to select for later maturing animals (http://www.nt.gov.au/dpifm). Since female redclaw stop growing at maturity, larger females are therefore less likely to have spawned: selecting the largest females as broodstock may affect selection for late maturing individuals.
The male reproductive system is composed of paired testes, vasa deferentia, and genital appendices; spermatogenesis occurs mainly in the seminal acini of the testes; spermatids formed after meiosis undergo a complicated metamorphosis until the aflagellate spermatozoa are formed (An et al., 2011).
Ovary physiology, oocyte development, and vitellogenesis have been described in many studies (Sagi et al., 1996b; Abdu et al., 2000, 2001, 2002; Soroka et al., 2000; Serrano-Pinto et al., 2003; Khalaila et al., 2004). For example, ovarian development of C. quadricarinatus females and the relationships among gonad maturation, oocyte development and the sequence of appearance of specific polypeptides in the ovary and the hemolymph were described by Abdu et al. (2000). Two anatomically distinctive types of primary-vitellogenic ovary were shown, one containing milky white oocytes and the other containing two diversely coloured oocyte populations. Secondary-vitellogenic ovaries are characterized by the presence of a synchronously growing large oocyte group together with oocytes of all the first four, primary-vitellogenic stages. Polypeptides of relatively low molecular masses (65-95 kDa) and of relatively higher molecular masses <100 kDa) were found in the primary-vitellogenic ovary and in the secondary-vitellogenic ovary (and newly laid eggs), respectively.
Mating consists in the male depositing a spermatophore on the underside of the female, from which sperm fertilizes eggs within 24 hours. The eggs are held under the female’s abdomen until they are ready to hatch – usually 6 to 8 weeks. The larvae develop within the eggs. Embryonic development, lasting 42 days at 26°C, consists of 10 prehatching and three posthatching stages (García-Guerrero et al., 2003). During embryonic development, eggs change colour from green to brown and orange. Finally the eggs hatch and the 12 mm long juveniles remain attached to the female for 1 to 2 days prior to moving away as completely independent miniature adults. The synchrony and degree of mating activity, the incubation period and the juvenile growth period is primarily influenced by water temperature (Lawrence and Jones, 2002).
With respect to other crayfish, such as Cherax destructor, female fecundity is relatively low, with 300-1,000 eggs per spawn. The number of both pleopodal eggs and juveniles (but not juvenile weight) was shown to be positively correlated to female size (King, 1993; Barki et al., 1997).
Under optimal pond conditions, redclaw can grow from hatching to the smallest marketable size (~30 g) within 4 months. When best practice techniques are used in farms, the majority of males will reach 100 g and females 70 g, within 12 months (http://www.nt.gov.au/dpifm).
Finally, an outstanding characteristic of C. quadricarinatus, which makes this species an ideal study model of sexual determination and plasticity, is the occurrence within populations, with a frequency of 2-14%, of intersex individuals (Medley and Rouse, 1993; Sagi et al., 1996a). Intersex individuals possess a male opening on one of the fifth pereopod and a female opening on the opposite third pereopod; they also possess an androgenic gland and an active testis on the side of the male opening and an ovary on the opposite side. They have male secondary sexual characteristics and function as males with an ovary in a permanently arrested, pre-vitellogenic state. Removal of the androgenic gland from intersex crayfish was found to induce the shift of the reproductive system from a permanently active male state to a female state. This included changes in morphology, cessation of spermatogenesis and onset of secondary vitellogenesis accompanied by the induction of the vitellogenin gene in the hepatopancreas (Sagi et al., 1996a).
Physiology and Phenology
Physiological studies have mostly focused on reproduction and its endocrine regulation (e.g. Khalaila et al., 2001, 2002; Shechter et al., 2005). For example, the role of the androgenic gland in the development of sex characters and physiology of the reproductive system was investigated by implanting hypertrophied androgenic glands (AG) into immature female animals (Khalaila et al., 2001). The large majority of females with AG implants developed male-like propodi, including the red patch characteristic of males of this species. The development of female secondary sex characteristics such as a wider abdomen, a wider endopod, and simple setation was inhibited. At the end of the experiment, the ovaries of the AG-implanted females contained mostly lipid-stage oocytes, with a small number of oocytes at the early yolk stage, showing that while secondary sex characters were masculinized under the influence of the implanted androgenic gland, the process of vitellogenesis was suppressed but not fully eliminated.
Physiological studies investigated the dynamics of calcium transport to transient calcium deposits (gastroliths) and to the cuticle over the course of the moult cycle (Shechter et al., 2008), and the activity of digestive enzymes (proteases, carbohydrases, and lipase) (Figueiredo et al., 2001) and of insulin-like growth factors (Richardson et al., 1997).
C. quadricarinatus is omnivorous, but in culture grows well on diets with a high proportion of cheap plant material (Lawrence and Jones, 2002). The optimal food for juveniles is zooplankton. They possess an array of digestive enzymes that enable digestion of a broad range of organic materials of animal and plant origin (Figueiredo et al., 2001). There is evidence of endogenous production of cellulases that enable redclaw to digest cellulose and similar sugars (Xue et al., 1999).
The harsh physical extremes of its distribution in tropical Australia have given C. quadricarinatus a robust nature with broad tolerances, particularly in the case of Queensland strains. Over 70% of adults’ growth occurs in the range 23-31°C. Maximum growth rate of hatchlings occurs when the temperature is about 30°C and growth ceases when the temperature falls to 15°C or rises to 35°C; their thermal tolerance range between 22°C and 32°C (King, 1994). Lethal limits are around 9-10°C and 34-35°C. Reproduction will only occur while water temperature remains above 23°C.
The survival of C. quadricarinatus in earthen ponds under ambient winter temperatures was studied in the temperate zone in the central coastal plain of Israel by Karplus et al. (1998). Notwithstanding that minimum daily temperatures of under 10°C were recorded on 6 days, overall survival was 60% and change in weight was minimal. It can survive short periods of exposure to low temperatures (5°C).
Tolerance to salinities as high as 12 ppt for extended periods have also been established for this species. This is advantageous for aquaculture. Firstly, aquaculture in mildly brackish water may be possible, and secondly, a final purging in salt water prior to marketing can be performed if markets request it. Generally crayfish is marketed as a premium seafood product with a delicate flavour.
Redclaw is able to survive under conditions of very low dissolved oxygen (1 ppm). If dissolved oxygen in the pond water drops below 1 ppm, redclaw will move to the edge of the pond where oxygen levels are generally higher, and in extreme cases will migrate from the pond over land.
Meade and Watts (1995) investigated survival rates of juvenile redclaw under exposure to different concentrations of ammonia, nitrite, and nitrate. The relative tolerances of crayfish to these substances are similar to those reported for other crustacean species. No mortalities were observed in crayfish exposed to up to 25 mg L-1 total ammonia concentration, up to 10 mg L-1 nitrite concentration, and up to 1000 mg L-1 nitrate concentration. Crayfish exposed to 50, 100, and 200 mg L-1 total ammonia concentrations survived an average of 40, 36, and 14 h, respectively. Crayfish exposed to 25, 50, and 100 mg L-1 nitrite concentrations survived an average of 96, 22, and 5 h, respectively.
Saker and Eaglesham (1999) showed that redclaw harvested from an aquaculture pond infested by a bloom of the cyanobacterium Cylindrospermopsis raciborskii were shown to accumulate the toxic alkaloid cylindrospermopsin. Pond water samples collected during the bloom contained 589 μg l−1 of the toxin and crayfish from the pond contained cylindrospermopsin at concentrations of 4.3 μg per g dried hepatopancreas tissue and 0.9 μg per g dried muscle tissue. Trichomes of C. raciborskii were observed in gut contents of crayfish harvested during the cyanobacterial bloom, indicating that the most likely mechanism for accumulation of the toxin was by ingestion of cyanobacterial cells.
Natural Food SourcesTop of page
|Food Source||Food Source Datasheet||Life Stage||Contribution to Total Food Intake (%)||Details|
|benthic micro and meio fauna||Aquatic|Adult; Aquatic|Broodstock; Aquatic|Fry||50|
|decaying organic material||Aquatic|Adult; Aquatic|Broodstock; Aquatic|Fry||50|
ClimateTop of page
|A - Tropical/Megathermal climate||Preferred||Average temp. of coolest month > 18°C, > 1500mm precipitation annually|
|B - Dry (arid and semi-arid)||Tolerated||< 860mm precipitation annually|
|C - Temperate/Mesothermal climate||Preferred||Average temp. of coldest month > 0°C and < 18°C, mean warmest month > 10°C|
|Cf - Warm temperate climate, wet all year||Preferred||Warm average temp. > 10°C, Cold average temp. > 0°C, wet all year|
|Cs - Warm temperate climate with dry summer||Tolerated||Warm average temp. > 10°C, Cold average temp. > 0°C, dry summers|
|Cw - Warm temperate climate with dry winter||Tolerated||Warm temperate climate with dry winter (Warm average temp. > 10°C, Cold average temp. > 0°C, dry winters)|
Air TemperatureTop of page
|Parameter||Lower limit||Upper limit|
|Mean annual temperature (ºC)||20||30|
|Mean maximum temperature of hottest month (ºC)||30||35|
|Mean minimum temperature of coldest month (ºC)||0||10|
Water TolerancesTop of page
|Parameter||Minimum Value||Maximum Value||Typical Value||Status||Life Stage||Notes|
|Ammonia [unionised] (mg/l)||>1||Harmful||Egg||Under culture conditions|
|Ammonia [unionised] (mg/l)||>1||Harmful||Fry||Under culture conditions|
|Ammonia [unionised] (mg/l)||>3||Harmful||Adult||Under culture conditions|
|Ammonia [unionised] (mg/l)||>3||Harmful||Broodstock||Under culture conditions|
|Ammonia [unionised] (mg/l)||0||Optimum||Adult||Under culture conditions|
|Ammonia [unionised] (mg/l)||0||Optimum||Broodstock||Under culture conditions|
|Ammonia [unionised] (mg/l)||0||Optimum||Egg||Under culture conditions|
|Ammonia [unionised] (mg/l)||0||Optimum||Fry||Under culture conditions|
|Ammonium [ionised] (mg/l)||>1||Harmful||Egg||Under culture conditions|
|Ammonium [ionised] (mg/l)||>1||Harmful||Fry||Under culture conditions|
|Ammonium [ionised] (mg/l)||>3||Harmful||Adult||Under culture conditions|
|Ammonium [ionised] (mg/l)||>3||Harmful||Broodstock||Under culture conditions|
|Ammonium [ionised] (mg/l)||0||Optimum||Adult||Under culture conditions|
|Ammonium [ionised] (mg/l)||0||Optimum||Broodstock||Under culture conditions|
|Ammonium [ionised] (mg/l)||0||Optimum||Egg||Under culture conditions|
|Ammonium [ionised] (mg/l)||0||Optimum||Fry||Under culture conditions|
|Bicarbonate (mg/l)||Optimum||Egg||Under culture conditions|
|Dissolved oxygen (mg/l)||<2||Harmful||Adult||Under culture conditions|
|Dissolved oxygen (mg/l)||<4||Harmful||Broodstock||Under culture conditions|
|Dissolved oxygen (mg/l)||<6||Harmful||Egg||Under culture conditions|
|Dissolved oxygen (mg/l)||<6||Harmful||Fry||Under culture conditions|
|Dissolved oxygen (mg/l)||7||Optimum||Adult||Under culture conditions|
|Dissolved oxygen (mg/l)||7||Optimum||Broodstock||Under culture conditions|
|Dissolved oxygen (mg/l)||7||Optimum||Egg||Under culture conditions|
|Dissolved oxygen (mg/l)||7||Optimum||Fry||Under culture conditions|
|Dissolved oxygen (mg/l)||Optimum||1 ppm tolerated in the natural environment|
|Hardness (mg/l of Calcium Carbonate)||<20||Harmful||Adult||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||<20||Harmful||Broodstock||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||<20||Harmful||Egg||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||<20||Harmful||Fry||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||40||100||Optimum||Adult||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||40||100||Optimum||Broodstock||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||40||100||Optimum||Egg||Under culture conditions|
|Hardness (mg/l of Calcium Carbonate)||40||100||Optimum||Fry||Under culture conditions|
|Illumination (Lux illuminance)||<250||Optimum||Adult||Under culture conditions|
|Illumination (Lux illuminance)||<250||Optimum||Broodstock||Under culture conditions|
|Illumination (Lux illuminance)||<250||Optimum||Egg||Under culture conditions|
|Illumination (Lux illuminance)||<250||Optimum||Fry||Under culture conditions|
|Magnesium (mg/l)||5||Optimum||Adult||Under culture conditions|
|Magnesium (mg/l)||5||Optimum||Broodstock||Under culture conditions|
|Magnesium (mg/l)||5||Optimum||Egg||Under culture conditions|
|Magnesium (mg/l)||5||Optimum||Fry||Under culture conditions|
|Nitrate (mg/l)||>50||Harmful||Adult||Under culture conditions|
|Nitrate (mg/l)||>50||Harmful||Broodstock||Under culture conditions|
|Nitrate (mg/l)||>50||Harmful||Egg||Under culture conditions|
|Nitrate (mg/l)||>50||Harmful||Fry||Under culture conditions|
|Nitrate (mg/l)||0||Optimum||Adult||Under culture conditions|
|Nitrate (mg/l)||0||Optimum||Broodstock||Under culture conditions|
|Nitrate (mg/l)||0||Optimum||Egg||Under culture conditions|
|Nitrate (mg/l)||0||Optimum||Fry||Under culture conditions|
|Nitrite (mg/l)||>1||Harmful||Egg||Under culture conditions|
|Nitrite (mg/l)||>1||Harmful||Fry||Under culture conditions|
|Nitrite (mg/l)||>3||Harmful||Adult||Under culture conditions|
|Nitrite (mg/l)||>3||Harmful||Broodstock||Under culture conditions|
|Nitrite (mg/l)||0||Optimum||Adult||Under culture conditions|
|Nitrite (mg/l)||0||Optimum||Broodstock||Under culture conditions|
|Nitrite (mg/l)||0||Optimum||Egg||Under culture conditions|
|Nitrite (mg/l)||0||Optimum||Fry||Under culture conditions|
|Potassium (mg/l)||1||Optimum||Adult||Under culture conditions|
|Potassium (mg/l)||1||Optimum||Broodstock||Under culture conditions|
|Potassium (mg/l)||1||Optimum||Egg||Under culture conditions|
|Potassium (mg/l)||1||Optimum||Fry||Under culture conditions|
|Salinity (part per thousand)||>15||Harmful||Adult||Under culture conditions|
|Salinity (part per thousand)||>5||Harmful||Broodstock||Under culture conditions|
|Salinity (part per thousand)||>5||Harmful||Egg||Under culture conditions|
|Salinity (part per thousand)||>5||Harmful||Fry||Under culture conditions|
|Salinity (part per thousand)||0||Optimum||Adult||Under culture conditions|
|Salinity (part per thousand)||0||Optimum||Broodstock||Under culture conditions|
|Salinity (part per thousand)||0||Optimum||Egg||Under culture conditions|
|Salinity (part per thousand)||0||Optimum||Fry||Under culture conditions|
|Salinity (part per thousand)||Optimum||12 tolerated in the natural environment|
|Spawning temperature (ºC temperature)||20||30||Harmful||Broodstock||Under culture conditions|
|Spawning temperature (ºC temperature)||26||29||Optimum||Broodstock||Under culture conditions|
|Water pH (pH)||<7||>9.5||Harmful||Fry||Under culture conditions|
|Water pH (pH)||<7.0||>9.5||Harmful||Adult||Under culture conditions|
|Water pH (pH)||<7.0||>9.5||Harmful||Broodstock||Under culture conditions|
|Water pH (pH)||7.0||8.5||Optimum||Adult||Under culture conditions|
|Water pH (pH)||7.0||8.5||Optimum||Broodstock||Under culture conditions|
|Water pH (pH)||7.0||8.5||Optimum||Egg||Under culture conditions|
|Water pH (pH)||7.0||8.5||Optimum||Fry||Under culture conditions|
|Water pH (pH)||7.0||9.0||Harmful||Egg||Under culture conditions|
|Water temperature (ºC temperature)||<10||>35||Harmful||Adult||Under culture conditions|
|Water temperature (ºC temperature)||<20||>30||Harmful||Broodstock||Under culture conditions|
|Water temperature (ºC temperature)||10||32||Harmful||Fry||Under culture conditions|
|Water temperature (ºC temperature)||20||30||Harmful||Egg||Under culture conditions|
|Water temperature (ºC temperature)||25||30||Optimum||Adult||Under culture conditions|
|Water temperature (ºC temperature)||25||30||Optimum||Fry||Under culture conditions|
|Water temperature (ºC temperature)||26||29||Optimum||Broodstock||Under culture conditions|
|Water temperature (ºC temperature)||26||29||Optimum||Egg||Under culture conditions|
|Water temperature (ºC temperature)||24-30||Optimum||In the natural environment. 10-35 tolerated, lethal limits are around 9-10 and 34-35. Reproduction will only occur while temperature remains above 23|
Natural enemiesTop of page
|Natural enemy||Type||Life stages||Specificity||References||Biological control in||Biological control on|
|Aphanomyces astaci||Pathogen||Aquatic|Adult; Nematodes|Juveniles||not specific|
|baculovirus of blue crayfish||Pathogen||Aquatic|Adult||not specific|
|Hydromys||Predator||Aquatic|Adult; Aquatic|Broodstock; Aquatic|Fry||Lawrence and Jones (2002)|
|Phalacrocoracidae||Predator||Aquatic|Adult; Aquatic|Broodstock; Aquatic|Fry||Lawrence and Jones (2002)|
Notes on Natural EnemiesTop of page
As with other Australian species, C. quadricarinatus would likely be susceptible to the effects of the crayfish plague caused by the oomycete Aphanomyces astaci. In Australia, the redclaw is known to harbour a variety of disease-causing organisms including protozoans, bacteria, and viruses. A well-studied virus is Cherax baculovirus (Edgerton and Owens, 1997), which has been implicated in mortalities and poor production in culture facilities, although there has never been any documented widespread outbreak (Edgerton, 1999).
Rickettsia-like organisms have been isolated from C. quadricarinatus and are considered to be a significant pathogen of this species, causing mortalities in cultured populations in northern Queensland and Ecuador (Edgerton et al., 1995; Romero et al., 2000). Psorospermium sp. and the microsporidian Thelohania have also been found in Australian populations (Herbert, 1987; Edgerton et al., 1995). Ciliate epibionts (Zoothamnium, Vorticella and Lagenophrys) and the endoparasite belonging to the Tetrahymena pyriformis complex were identified in populations in Queensland (Herbert, 1987; Edgerton et al., 1995).
Temnocephalid flatworms (Platyhelminthes: Temnocephalida) have been found on this species, including specimens imported into Europe for growth trials. Four species have been identified (Cannon, 1991): Temnocephala rouxii, Notodactylus handschini, Diceratocephala boschmai, and Decadidymus gulosus.
The main predators of C. quadricarinatus in Australia are birds, eels, and water rats.
Means of Movement and DispersalTop of page
No studies to date have investigated the active movement and dispersal of C. quadricarinatus.
Pathway CausesTop of page
Pathway VectorsTop of page
Impact SummaryTop of page
|Fisheries / aquaculture||Positive|
Economic ImpactTop of page
C. quadricarinatus possesses a range of biological attributes that make it an ideal candidate for semi-intensive aquaculture (Lawrence and Jones, 2002). Redclaw have a very simple life cycle: as such, the technology needed to manage the life cycle is relatively simple. Broodstock are readily available from existing pond stocks, which also facilitates the selection of broodstock with advantageous characteristics such as a fast growth rate or high fecundity. Genetic selection and domestication of farm stocks can increase growth rates and yields by as much as 10% per generation.
Notwithstanding these characteristics, industry has developed relatively slowly in Australia and elsewhere in the world. This is due to the recent interest in this species, which arose in the late 1980s (Lawrence and Jones, 2002), but also to the cost of setting up and maintaining redclaw farms. Redclaw aquaculture cannot be successful on a part-time basis or by using an extensive approach. As noted by Lawrence and Jones (2002), “it is intensive farming, requiring substantial funds, a commitment to excellence and the application of proven practices, full-time, just like every other economically viable primary production.”
Environmental ImpactTop of page
The implications of the occurrence of C. quadricarinatus for the ecology of the invaded systems are unknown. It has been hypothesized that in Western Australia it can outcompete three indigenous species of Macrobrachium prawns (Macrobrachium australiense, M. bullatum, and M. spinipes) and three species of atyiid shrimp (Caridina cf. longirostris, C. nilotica, and C. serratirostris) (Lynas et al., 2007).
In Mexico, concerns regard the impact that redclaws could have on the native fauna, through direct competition and predation, as well as its potential to transmit new parasites (Bortolini et al., 2007).
Impact: BiodiversityTop of page
See Impact: Environmental.
Social ImpactTop of page
No negative social impact is known. The possibility exists that this species might be a vector of parasites and diseases that might affect humans. As shown by Saker and Eaglesham (1999), it can accumulate toxins of cyanobacteria in its tissues and organs.
C. quadricarinatus is recreationally fished on a small scale throughout its natural range.
Risk and Impact FactorsTop of page
- Abundant in its native range
- Highly adaptable to different environments
- Is a habitat generalist
- Capable of securing and ingesting a wide range of food
- Benefits from human association (i.e. it is a human commensal)
- Long lived
- Fast growing
- Has high reproductive potential
- Pest and disease transmission
- Rapid growth
- Highly likely to be transported internationally deliberately
- Highly likely to be transported internationally illegally
- Difficult/costly to control
UsesTop of page
Fast growth rates, relative ease of reproduction, lack of any free-living larval stages, gregariousness, and the ability to tolerate poor water quality conditions are characteristics that make C. quadricarinatus an optimal species for aquaculture. Interest in this species stimulated research which has led to the development of optimum husbandry and best practice techniques. Even so, the redclaw farming industry has not lived up to early expectations and predictions, and production has remained relatively low (Lawrence and Jones, 2002).
In Australia, the industry is composed of a great number of small enterprises making the marketing quite fragmented. Recently, localized marketing groups composed of cooperative growers have emerged.
In Australia, redclaw are marketed in 20-g size grades ranging from 30 to 50 g at about AUS $11.50 kg-1 to greater than 120 g at about AUS $19 kg-1. After harvesting, mostly through the application of flow traps, stock are held in tanks with a flow-through water supply or a recirculating system with biological filtration and maintained in the tank for at least 24 h to permit purging of the gut. Packing involves insulated containers with moist packing material and cooling packs for their transport and sell live. At present, 50% of redclaw are sold within Queensland, 30% interstate, and 20% are exported (Lawrence and Jones, 2002). Redclaw aquaculture is still a niche sector of the broader aquaculture industry producing low volumes of product for local markets.
Commercial production and sale of broodstock and juveniles have occurred in the USA since 1990s (Lawrence and Jones, 2002). Farm development has occurred in Ecuador, commencing in 1994 (Romero, 1997) and leading to over 250 ha of redclaw ponds constructed between 1994 and 1997 (Romero, 1997). Despite initial success, the redclaw farming industry declined rapidly in Ecuador, with only 80-100 tons produced in 2000 and two farms still active (Lawrence and Jones, 2002; Romero, 2002). Redclaw was introduced into New Caledonia in 1992 and 21 farms were set up on the western side of the island. Southern provinces of China have imported several million redclaw juveniles. In Europe, and particularly in Britain and Spain, it is sold in the aquarium trade. Redclaw were introduced to Israel from the USA in the early 1990s by the Department of Fisheries, Ministry of Agriculture; experimentation was carried out at the Agricultural Research Organization at Bet Dagan and the Aquacultural Research Station, Ministry of Agriculture, Dor. The species is now raised in Kfar Monash, on the central coastal plain, where intensive farming is able to provide up to 100,000,000 juveniles to distributors and ornamental shop chains in Israel and Europe (http://www.aquology.com).
In Australia, production is 70 tons per annum, with a yield 1000-4000 kg ha-1crop-1. Few production data are available for European countries. Ackefors (2000) reported that the combined production of C. destructor and C. quadricarinatus from aquaculture in Europe in 1994 was 3.7 tons.
Uses ListTop of page
- Pet/aquarium trade
- Research model
- Sport (hunting, shooting, fishing, racing)
Human food and beverage
- Meat/fat/offal/blood/bone (whole, cut, fresh, frozen, canned, cured, processed or smoked)
Similarities to Other Species/ConditionsTop of page
C. quadricarinatus can be distinguished from C. destructor and C. tenuimanus by the presence of four keels, and the coloured patch on the male chela (Souty-Grosset et al., 2006).
Prevention and ControlTop of page
Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.
Most efforts should be directed to developing detection and inspection methods, diagnosis, and prevention (including early warning system, rapid response, and public awareness). Risk assessment protocols should be developed to quantify the magnitude of the impact of this potential invader on the recipient ecosystems (Tricarico et al., 2009). The likelihood of unintentional introductions through merchandise imports could be reduced through more strict control procedures.
No attempts have been made to control potentially invasive feral populations of the species.
Gaps in Knowledge/Research NeedsTop of page
Most studies have focussed on analyzing methods to make cultivation of this species more profitable. Very few studies have been made on feral populations. There is scarce information about the position of C. quadricarinatus in the food web of natural ecosystems and nothing is yet known about its possible negative impact to the environment, as well as to human activities and health.
ReferencesTop of page
Abdu U, Davis C, Khalaila I, Sagi A, 2002. The vitellogenin cDNA of Cherax quadricarinatus encodes a lipoprotein with calcium binding ability, and its expression is induced following the removal of the androgenic gland in a sexually plastic system. General and Comparative Endocrinology, 127(3):263-272
Abdu U, Yehezkel G, Sagi A, 2000. Oocyte development and polypeptide dynamics during ovarian maturation in the red-claw crayfish Cherax quadricarinatus. Invertebrate Reproduction and Development, 37(1):75-83
Abdu U, Yehezkel G, Weil S, Ziv T, Sagi A, 2001. Is the unique negatively charged polypeptide of crayfish yolk HDL a component of crustacean vitellin? Journal of Experimental Zoology, 290:218-226
Ahyong ST, Yeo DCJ, 2007. Feral populations of the Australian red-claw crayfish (Cherax quadricarinatus von Martens) in water supply catchments of Singapore. Biological Invasions, 9:943-946
An ChuanGuang, Weng XianLong, Xu YongZhen, Fan YuJie, Zhao YunLong, 2011. Histological and ultrastructural studies on the male reproductive system and spermatogenesis in the red claw crayfish, Cherax quadricarinatus. Journal of Crustacean Biology, 31(2), 223-230. http://www.bioone.org/doi/full/10.1651/10-3342.1 doi: 10.1651/10-3342.1
Anonymous, 1997. Aquaculture of non-endemic species in Western Australia, redclaw crayfish. Aquaculture of non-endemic species in Western Australia, redclaw crayfish. [Fisheries Management Paper No. 100.]
Baker N, Bruyn Mde, Mather PB, 2008. Patterns of molecular diversity in wild stocks of the redclaw crayfish (Cherax quadricarinatus) from northern Australia and Papua New Guinea: impacts of Plio-Pleistocene landscape evolution. Freshwater Biology, 53(8):1592-1605
Belle CC, Yeo DCJ, 2010. New observations of the exotic Australian red-claw crayfish, Cherax quadricarinatus (von Martens, 1868) (Crustacea: Decapoda: Parastactidae) in Singapore. Nature in Singapore, 3:99-102
Bortolini JL, Alvarez F, Rodríguez-Almaraz G, 2007. On the presence of the Australian redclaw crayfish, Cherax quadricarinatus, in Mexico. Biological Invasions, 9(5):615-620. http://www.springerlink.com/content/j71700153298725g/fulltext.html
CABI, 2004. Datasheet on Cherax quadricarinatus. Aquaculture Compendium. Wallingford, UK: CABI. http://www.cabi.org/ac
Chang AKW, 2001. Analysis of the performance of a formulated feed in comparison with a commercial prawn feed for the crayfish, Cherax quadricarinatus. World Aquaculture, 32:19-23
Cortes-Jacinto E, Villarreal-Colmenares H, Civera-Cerecedo R, Naranjo-Paramo J, 2004. Effect of dietary protein level on the growth and survival of pre-adult freshwater crayfish Cherax quadricarinatus (von Martens) in monosex culture. Aquaculture Research, 35:71-79
Curtis MC, Jones CM, 1995. Observations on monosex culture of redclaw crayfish Cherax quadricarinatus von Martens (Decapoda: Parastacidae) in earthen ponds. Journal of the World Aquaculture Society, 26:154-159
Curtis MC, Jones CM, 1995. Overview of redclaw crayfish Cherax quadricarinatus farming practices in northern Australia. Freshwater Crayfish, 10:447-455
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Doupé RG, Morgan DL, Gill HS, Rowland AJ, 2004. Introduction of redclaw crayfish Cherax quadricarinatus (von Martens) to Lake Kununurra, Ord River, Western Australia: prospects for a 'yabby' in the Kimberley. Journal of the Royal Society of Western Australia, 87:187-191
Edgerton B, Owens L, 1997. Age at first infection of Cherax quadricarinatus by Cherax quadricarinatus bacilliform virus and Cherax Giardiavirus-like virus, and production of putative virus-free crayfish. Aquaculture, 152(1/4):1-12
Edgerton B, Owens L, Harris L, Thomas A, Wingfield M, 1995. Health survey of farmed redclaw crayfish Cherax quadricarinatus (Von Martens) in tropical Australia. Freshwater Crayfish, 10:322-338
Edgerton BF, 1999. Diseases of the redclaw freshwater crayfish. Aquaculture Magazine, 25:26-38
Figueiredo MSRB, Kricker JA, Anderson AJ, 2001. Digestive enzyme activities in the alimentary tract of redclaw crayfish, Cherax quadricarinatus (Decapoda: Parastacidae). Journal of Crustacean Biology, 21:334-344
Garcia Vazquez S, 2009. Distribution of exotic Australian crayfish Cherax quadricarinatus (von Martens, 1868) in Puerto Rico. Mayagüez, Puerto Rico: University of Puerto Rico, 70 pp
García-Guerrero M, Hendrickx ME, Villarreal U, 2003. Description of the embryonic development of Cherax quadricarinatus (Von Martens, 1868) (Decapoda, Parastacidae), based on the staging method. Crustaceana, 76:269-280
Groff JM, McDowell T, Friedman CS, Hedrick RP, 1993. Detection of a nonoccluded baculovirus in the freshwater crayfish Cherax quadricarinatus in North America. Journal of Aquatic Animal Health, 5(4):275-279
Gu H, Mather PB, Capra MF, 1994. The relative growth of chelipeds and abdomen and muscle production in male and female redclaw crayfish, Cherax quadricarinatus von Martens. Aquaculture, 123:249-257
Hinton AW, Jones CM, 1997. Redclaw Crayfish Farming, An Economic Perspective In: Redclaw Crayfish Aquaculture. Mareeba, Australia: Department of Primary Industries, 2-10
Holdich DM, Reynolds JD, Rogers WD, 1999. Native and alien crayfish in the British Isles. In: Crayfish in Europe as alien species. How to make the best of a bad situation? [ed. by Gherardi, F. \Holdich, D. M.]. Rotterdam, Netherlands: A.A. Balkema, 221-234
Holthuis LB, 1986. The freshwater crayfish of New Guinea. Freshwater Crayfish, 6:48-58
IUCN, 2010. IUCN Red List of Threatened Species (ver. 2010.3). IUCN Red List of Threatened Species (ver. 2010.3). http://www.iucnredlist.org
Johnston B, Jones CM, 2001. Redclaw Profit, Version 1.1. Brisbane, Australia: Department of Primary Industries
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Jones CM, Grady J, 2000. Redclaw from harvest to market: a manual of handling procedures. Brisbane, Australia: Department of Primary Industries, QI99083
Jones CM, McPhee CP, Ruscoe IM, 1998. Breeding redclaw: management and selection of broodstock. Brisbane, Department of Primary Industries, QI98016
Jones CM, McPhee CP, Ruscoe IM, 2000. A review of genetic improvement in growth rate in redclaw crayfish Cherax quadricarinatus (von Martens) (Decapoda: Parastacidae). Aquaculture Research, 31(1):61-67
Jones CM, Ruscoe I, 1996. Production Technology for Redclaw Crayfish (Cherax quadricarinatus). Final Report FRDC Project 92/119, Fisheries Research and Development Corporation, Canberra
Karplus I, Barki A, Cohen S, Hulata G, 1995. Culture of the Australian red-claw crayfish Cherax quadricarinatus in Israel: I. Polyculture with fish in earthen ponds. Israel Journal of Aquaculture, 47:6-16
Karplus I, Sagi A, Khalaila I, Barki A, 2003. The soft red patch of the Australian freshwater crayfish (Cherax quadricarinatus (von Martens)): a review and prospects for future research. Journal of Zoology, 259(4):375-379
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Khalaila I, Peter-Katalinic J, Tsang C, Radcliffe CM, Aflalo ED, Harvey DJ, Dwek RA, Rudd PM, Sagi A, 2004. Structural characterization of the N-glycan moiety and site of glycosylation in vitellogenin from the decapod crustacean Cherax quadricarinatus. Glycobiology, 14:767-774
King CR, 1994. Growth and survival of redclaw crayfish hatchlings (Cherax quadricarinatus Von Martens) in relation to temperature, with comments on the relative suitability of Cherax quadricarinatus and Cherax destructor for culture in Queensland. Aquaculture (Netherlands), 122(1):75-80
Koutrakis E, Perdikaris C, Machino Y, Savvidis G, Margaris N, 2007. Distribution, recent mortalities and conservation measures of crayfish in hellenic fresh waters. Bulletin Français de la Pêche et de la Piscicolture, 385:25-44
Lynas J, Storey A, Knott B, 2007. Introduction and spread of crayfish (Parastacidae) in Western Australia and their potential to displace indigenous species. In: Biological invaders in inland waters: profiles, distribution and threats [ed. by Gherardi, F.]. Dordrecht, The Netherlands: Springer, 577-596
Macaranas JM, Mather PB, Hoeben P, Capra MF, 1995. Assessment of genetic variation in wild populations of the redclaw crayfish (Cherax quadricarinatus, von Martens 1868) by means of allozyme and RAPD-PCR markers. Marine and Freshwater Research, 46(8):1217-1228
McPhee CP, Jones CM, Shanks SA, 2004. Selection for increased weight at nine months in Redclaw crayfish (Cherax quadricarinatus). Aquaculture, in press
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Williams Jr EW, Bunkley-Williams L, Lilyestrom CG, Ortiz-Corps EA, 2001. A review of recent introductions of aquatic invertebrates in Puerto Rico and implications for the management of nonindigenous species. In: Caribbean Journal of Science, 37 246-251.
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ContributorsTop of page
25/07/11 Updated by:
Francesca Gherardi, Dipartimento di Biologia Evoluzionistica 'Leo Pardi', Universita' degli Studi di Firenze, Via Romana 17, I-50125 Firenze, Italy
23/05/05 Original text by:
Clive Jones, Dept. of Primary Industries, Northern Fisheries Centre, Cairns, Australia
Reviewers' names are available on request.
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