C. Greg Lutz
Although Louisiana already has a diverse aquaculture industry, many more species could be grown here or grown on a larger scale. Many prospects present specific problems that could complicate commercial development, but most of these constraints relate to marketing, financing or regulatory considerations, not technical issues. This article addresses some of these potential species in the order of most promising to least promising. Hybrid striped bass
Perhaps the most promising finfish candidate for future commercial development in Louisiana is the hybrid striped bass. In the past decade, successful hybrid striped bass culture has been demonstrated in northeast, south-central and coastal areas of the state. Although Louisiana has more than18,000 acres of commercial catfish ponds, only 15,500 are in production. Many are suitable for commercial production of hybrid striped bass.
Existing markets for hybrid stripers are mostly on the East Coast. These outlets could probably absorb added production without significantly reducing profitability, but substantial increases in production will require distribution into new markets. Fortunately, this fish could potentially fill many supply gaps resulting from reduced availability of traditional species along the Gulf and Atlantic coasts. LSU Agricultural Center research on hybrid striped bass focuses on immunization against major diseases, potential for development of domesticated hybrid-based strains, production strategies to spread harvests throughout the year and other topics. Cocahoe minnows
The popularity of cocahoes as bait for recreational marine species has remained high. Commercial suppliers depend on wild-caught minnows, and they have failed to keep pace with demand. Techniques for culturing cocahoes were first investigated in Alabama in the 1970s. Later work in Texas outlined recommended approaches to cocahoe production, based on research and commercial results there and elsewhere. Net, after-tax revenues of $2,990 per water-acre were projected, and potential markets for farm-raised minnows were identified along most of the northern Gulf of Mexico. Aquatic plants
Louisiana has the climate, soil and water resources to propagate commercial algae, ornamental plants for aquariums and water gardens, and marsh and wetland vegetation for restoration or mitigation projects. Markets are expanding rapidly, and these aquatic crops could be quite profitable. Ornamental species
Increasing popularity of water gardens throughout the southeastern United States has created demand for koi carp and fancy goldfish. One of the country’s premier koi farms operates in Pointe Coupee Parish. Potential also exists for commercial production of many freshwater aquarium species in Plaquemines Parish, south of Pointe a la Hache, in small ponds similar to those used by producers in the Tampa Bay region. Tilapia
Tilapia is the common name for a group of tropical, perch-like species native to Africa and the Middle East but introduced to tropical regions worldwide. Tilapia production has increased dramatically in North America in response to Asian and Hispanic demand for live fish in metropolitan areas. Outdoor production of tilapia is legal in Arkansas, Mississippi and Texas, but Louisiana’s Department of Wildlife and Fisheries requires these fish to be kept in indoor recirculating systems to prevent their escaping to local waters. This increases production costs considerably, but reduces seasonality and depressed prices associated with the harvest of these tropical fish from ponds before the first cold front each winter.
Greenhouse-based systems developed by Louisiana growers and Cooperative Extension Service personnel achieve lower production costs than most other U.S. operations. Unfortunately, tilapia farms have been constructed throughout the United States in recent years, and prices in live markets have plummeted as a result. For the past eight to 10 months, most tilapia going to live markets have been sold at significantly less than production cost because late arrivals to the industry have been faced with the need to service start-up debt.
In Central America, northern South America and the Caribbean basin, commercial production of tilapia has expanded rapidly to target North American fillet markets. If U.S. tilapia producers are to avoid substantial losses and compete in fillet markets, production costs must be further reduced through adoption of improved stocks. Research in this area is a cooperative effort of the LSU Ag Center and commercial producers. Results from analyses of Louisiana greenhouse systems suggest that using faster growing strains in conjunction with improved filtration systems could potentially lower costs to produce and deliver fresh fillets to levels comparable with estimates for imported product. Softshell crawfish
The seasonality that has plagued the softshell crawfish industry might be reduced by using an alternative, complementary species of crawfish. Orconectes lancifer is a shrimp-like crawfish native to many parts of Louisiana. It tolerates high temperatures and low oxygen, spawns in late winter and grows throughout the summer and fall when normal supplies of shedding crawfish are unavailable. Redfish
A moratorium on commercial redfish, or red drum, harvests from the Gulf in the 1980s led researchers and entrepreneurs to devote considerable resources to the development of aquaculture techniques for this species. Budgets developed for red drum production in the late 1980s and early 1990s were based largely on preliminary research and optimistic assumptions. As experimental data from public institutions and private ventures became available, however, original estimates of profitability often proved overly inflated. Research and commercial efforts devoted to red drum culture declined steadily through the 1990s as temperature, disease and cash flow risks were increasingly perceived to outweigh the potential for profits.
Few areas of research stand out as avenues to expand commercial production of red drum. One approach that may hold some promise is recirculating tank production. In recent years, equipment options and management strategies available to producers who use indoor recirculating methods have improved dramatically. Red drum adapt fairly well to tank culture, as evidenced by success at various research facilities. Freshwater prawns
Production of the tropical Malaysian prawn is biologically feasible in many southeastern states, including Louisiana. As with tilapia, the need to complete pond harvests each fall before cold weather results in marketing constraints. Additional problems relate to limited availability and high cost of juveniles for stocking in late spring. Ag Center research with this species focuses on production of all-male or sterile stocks in an effort to improve yields and reduce size variability at harvest. Eels
Eels have long been a valuable aquaculture crop in Europe and the Far East. Captive spawning is not practical, but production technologies are well documented, and wild-caught elvers are occasionally available along the Gulf Coast. Although global competition might limit export opportunities for this species, regional and live markets might absorb considerable production. Hybrid bream
This fish is primarily a live market item, but there is limited demand for dressed fish in New York as well as Chicago and other Midwestern markets. The degree to which prices will drop with any increase in supply remains to be seen. Shrimp
Little or no potential exists for economically viable marine shrimp farming in Louisiana, but sophisticated hatchery operations producing highquality, pathogen-free post-larvae for export to shrimp-producing countries in Central and South America could be profitable. Bullfrogs
Several major problems with frog culture remain unsolved. When combined with comparatively high land and labor costs and limited growing seasons, these constraints have prevented the development of commercial frog culture in the United States. Up to 1.15 pounds of live food is required to produce a single 0.4- pound bullfrog destined for the frog leg market, and bullfrogs will not voluntarily consume artificial diets that lack the appropriate combination of movement, texture and flavor. Approaches to commercial frog culture in tropical regions can be adapted to allow laboratory-scale production of small frogs for research and teaching purposes, but high costs rule out commercial frog leg production in the Southeast. Offshore cage production
The technology exists to build offshore fish cages that can easily withstand conditions in the Gulf, and many offshore platforms are already in place to support production operations. No outstanding high-value candidate species presents itself for conditions in the Gulf, but future domestication efforts may result in availability of fingerlings of one or several species from the snapper-grouper complex or possibly some type of flatfish. Successful net-pen siting depends on finding currents that freshen the water within the net-pen on a continual basis and disperse feces and uneaten feed across a wide swath of water bottom to avoid buildup of anoxic sediments. Criticisms of net-pen farming in other parts of the world include the assertion that captive fish serve as reservoirs for diseases and parasites. Offshore production will probably require on-shore facilities for hatchery and nursery operations. These might have considerable siting problems in the coastal zone. On the horizon
A number of species are being considered or actually evaluated for commercial potential in the Southeast. When evaluating the ability of Louisiana producers to compete with imported products, key considerations for any species involve the relative costs of production, processing and distribution. In spite of high transportation costs, tilapia producers in Central and South America can put a fillet on the market in Louisiana for a much lower cost than local producers can. In the case of live fish or aquatic plants, however, high transportation and distribution costs far outweigh production advantages of foreign producers, effectively preventing competition from imports. As technology evolves and demand for seafood increases, it is almost a certainty that new species will become available to Louisiana producers. Technology and expertise, however, cannot foster aquaculture development in Louisiana without a parallel emphasis on regulatory, financial and marketing support for this industry.
C. Greg Lutz, Associate Specialist (Aquaculture), Louisiana Cooperative Extension Service, LSU Agricultural Center, Baton Rouge, La.
(This article was published in the fall 1999 issue of Louisiana Agriculture.)