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Pond production

Red claw are probably best produced in traditional fish production ponds 3 to 4 feet deep with sloping bottoms and a drainage system. Ponds ranging from 1/4 to 2 acres have been used in red claw production, but ponds of 1 acre or less are recommended for ease of management and harvesting. Research suggests the following production strategy:

1. Stock juveniles of 1 gram or larger in the spring when water temperatures stay above 68oF;

2. Stock at a density of 10,000 to 12,000 per surface acre of pond;

3. Feed hay at 225 kg per acre per month and supplement with a commercial diet at 3 percent of estimated biomass

4. Partial harvest using traps starting 3 to 4 months after the young crayfish were stocked

5. Drain harvest when water temperatures drop below 60oF.

To reduce the chance of disease and competition, native crayfish should be eliminated from ponds in which  red claw will be stocked. Fill the ponds with well water if possible to eliminate introduction of other species and their diseases. Ponds should be filled only a few weeks before stocking to prevent the establishment of predaceous aquatic insects. Ponds should be limed if hardness is below 20 ppm and fertilized to establish a plankton bloom. Survival improves significantly if a 1 gram (28 to the ounce) or larger juvenile is stocked rather than newlyhatched juveniles. Stocking densities of 0.25 to 0.3 per square foot of pond surface area (10,000 to 12,000 per acre) appear to give the best overall survival and production of larger crayfish. Dried hay should be spread around the edges of the pond monthly at a rate of about 225 kg per acre per  month, divided into two or three applications. Commercial crayfish, shrimp, or fish feeds should be used in addition to the hay during the last half of the culture period. Total commercial feed input should be fed at 3 percent of estimated total crayfish weight per day but not to exceed 15 kg per pond surface acre per day.

Water quality must be maintained if red claw are to survive and grow. Aeration should be used to maintain dissolved oxygen above 3 ppm. Remember that these animals live on the pond bottom; therefore, oxygen should be checked near the pond bottom and not at the surface. Ammonia and nitrite concentrations should
be determined twice weekly toward the end of the growing season, but are not usually a problem at  recommended feeding rates. If water quality declines, stop feeding and flush with clean water, if possible. Red claw may attempt to migrate from the pond if water quality is poor. Proper management should lead to the
production of 450 to 680 kgs per acre after six months. Individual red claw should weigh about 70  grams or 14 to the kg, although some individuals will weigh more than 1/8 kg.

Harvesting

Red claw can be harvested by using baited crayfish traps, flowtraps, and by draining the pond. Crayfish traps used to catch native crayfish can be used for red claw. These traps are made of 3/4- inch plastic coated  chicken wire mesh (Figure 7). Both stand-up and pyramid traps have been used effectively. Baits include formulated commercial crawfish baits and fish feed contained in small mesh bags. Final harvesting is done by partially draining the pond (to 1/4 of original size) and setting up a flow-trap. Flow-traps are traps through
which water moves or flows. Red claw are strongly attracted to moving water, possibly an adaptive response to spring floods in their natural environment. Research suggests that flow-traps are very successful at capturing
crayfish. Pumping rates in flowtraps should not exceed 8 gallons per minute, and water from another pond or a well appears to work better than water from the same pond. One flow-trap design is the box-n ramp trap.

The box-n-ramp trap consists of an impervious box (e.g., plastic trash can or metal drum) into which water is
pumped and a ramp which carries the out-flow water to the pond bottom (Figure 7). The crayfish move up the ramp against the flow and are trapped when they fall into the box. Adding fiberglass screen, vexar, or some other rough texture to the surface of the ramp will help the crayfish climb into the trap. Flow-traps must be checked often (every few hours) as they can fill with crayfish, causing those in the bottom of the trap to suffocate.

Diseases

Red claw are probably susceptible to most diseases that affect native crayfish. In addition, red claw are susceptible to the “crawfish plague” which is a fungal pathogen. Native North American crayfish carry the plague but are usually not adversely affected by it. The fungus was not known to be a problem until North American crayfish were introduced to Europe over 100 years ago.

European crayfish had no resistance or immunity to the North American pathogen and many natural populations were devastated. Research has shown that the red claw are susceptible to this fungus. The fungus grows best at temperatures below 65oF and does not appear to be active or pathogenic above 70oF. Since red claw need temperatures above 70oF for good growth, careful attention to stocking and harvesting temperatures may reduce potential problems. There are no known methods of prevention and treatment of the plague.

Marketing

No one knows what price red claw crayfish will bring in the Asean Region. A market for red claw will have to be developed. If red claw have to compete in the native crayfish market their production will not be economically feasible. Because of its size (100 to 300 per gram), however, it should fall into a totally new market niche and not compete with native crayfish or large lobsters. Contacts with marketing specialists indicate that red claw should have high appeal and command a high price when sold as “small lobsters.” Until large numbers are available, however, all marketing potential is speculative.

One advantage of red claw will be the ability to market live,whole animals without any need for processing. One advantage will be the development of a yearround supply since production cycles will not be limited by cold weather in the Asean region production. Most juvenile red claw currently produced in the Southeast are being sold to the ornamental or aquarium market. The color (light blue) and uniqueness of the red claw have demanded high prices from aquarium enthusiasts. Again, even this market has to be developed by individual producers.

Financial considerations

Red claw farming, like any type of agricultural enterprise, is a risky venture. Red claw farming is even more risky since little is known about full scale commercial production problems, diseases, and potential markets. Failures (to some degree) are still the rule and not the exception in  aquaculture when it involves new species. All commercial ventures should be preceded by appropriate pilot scale operations. It is prudent that beginning producers be conservative. Start slowly, minimizecapital investment, keep overhead low, and develop markets (i.e., start small and learn as you go).