WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2015 65 Australian red claw crayfish Cherax quadricarinatus (Fig. 1) are tropical crustaceans native to Northern Australia, Queensland and Papua New Guinea. Commonly found in creeks and rivers, red claw crayfish are characterized by aggressive and non-burrowing behavior. The term “red claw” is derived from the red cartilaginous patch present on the lateral side of each claw in mature males. They are desirable as an aquaculture species because of their lack of larval stages, non-burrowing behavior, rapid growth rate and relatively large market size (Webster et al. 2004). Commercial production of red claw crayfish in the United States is done primarily at a small scale in freshwater ponds when water temperature is between 21 and 32 C. They typically reach market size (80200 g) in 6 to 9 months under optimal growing conditions (Webster et al. 2004). As such, adult red claw crayfish can be marketed as “freshwater lobsters.” Economic Importance Red claw crayfish are sold predominately as a food product in the United States. Inasmuch as they can have vivid coloration, they are also sold as ornamentals in the aquarium trade. The economics and marketing of red claw crayfish have not been thoroughly investigated in the United States. This is partly a result of the scant production of this species in the country. In Kentucky, the aquaculture sector operates at a small scale, with a typical farm having 0.1 to 2-ha ponds. This makes red claw crayfish production amenable to niche marketing, where a small volume of product can be sold in markets with a high demand. The greatest difficulty in marketing red claw crayfish may be the low levels of production, resulting in the inability to exploit multiple markets, something that is true for many states (Saoud et al. 2013). However, the low level of production can make red Production Trial of Juvenile Australian Red Claw Crayfish in an Indoor Nursery Grant C. Curran, Siddhartha Dasgupta and Kenneth R. Thompson claw crayfish aquaculture profitable when marketed as freshwater lobsters or small lobsters (Masser and Rouse 1997). Motivation In a temperate climate, red claw crayfish can only be grown outdoors when pond temperatures reach optimal ranges, limiting the growing season to 3-5 months (Webster et al. 2004). This has prompted red claw crayfish producers to move production indoors to extend the growing season (Rodriguez-Canto et al. 2002). Pond-based producers in the United States require red claw crayfish juveniles, for which there are no regional suppliers. Buying juveniles from hatcheries in Mexico and Australia is cost prohibitive. Consequently current US-based research is investigating the feasibility of developing indoor hatchery and nursery systems that allow producers to maintain their own supply of juvenile crayfish. Red claw crayfish can be hatched and nursed in the same water body because they lack larval stages that are typically present in other species of cultured crustaceans, such as freshwater prawns. Additionally, juvenile red claw crayfish do not require brine shrimp as a food source and can be fed the same feed pellets as adults, which is a substantial economic, logistical, and management advantage over the culture of freshwater prawn, which needs brine shrimp during larval stages. Various hatchery protocols have been developed for red claw crayfish (Masser and Rouse 1997); however, there is a lack of protocols for the nursery stage of these animals. In an effort to establish a nursery protocol, a 60-d trial was performed in a wet lab at the Aquaculture Research Center of Kentucky State University. (CONTINUED ON PAGE 66) FIGURE 1. Adult male red claw crayfish Cherax quadricarinatus. FIGURE 2. Size-grading juvenile red claw crayfish prior to stocking in nursery tanks.
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