…leading expert on VHS in the United States, Jim Winton of the US Geological Survey, indicated that the VHS virus exists in four strains, with a single, unique sub-strain occurring in the Great Lakes. The VHS virus has been known in Europe, Japan, and the coasts of the U.S. for many years; how it came to occur in the Great Lakes is not known. Winton speculates that it may have originated in ballast water from ocean-going ships sailing into the Great Lakes, or that it may have hitchhiked in shipments of hatchery-raised fish.

According to the New York State Department of Environmental Conservation (NYSDEC),

Viral hemorrhagic septicemia (VHS) virus is a serious pathogen of fresh and saltwater fish that is causing an emerging disease in the Great Lakes region of the United States and Canada. VHS virus is a rhabdovirus (rod shaped virus) that affects fish of all size and age ranges. It does not pose any threat to human health. VHS can cause hemorrhaging of fish tissue, including internal organs, and can cause the death of infected fish. Once a fish is infected with VHS, there is no known cure. Not all infected fish develop the disease, but they can carry and spread the disease to other fish. VHS has been blamed for fish kills in Lake Huron, Lake St. Clair (MI), Lake Erie, Lake Ontario, the St. Lawrence River and Conesus Lake (Western NY). The World Organization of Animal Health has categorized VHS as a transmissible disease with the potential for profound socio-economic consequences. Because of this, they list VHS as a disease that should be reported to the international community as an exceptional epidemiological (study of diseases in large populations) occurrence.

The NYSDEC has released revised Emergency Regulations Adopted to Prevent Spread of VHS.

Animal and Plant Health Inspection Service (APHIS) note the following species are susceptable: Atlantic cod Gadus morhua, Black crappie Pomoxis nigromaculatus, Bluegill Lepomis macrochirus, Bluntnose minnow Pimephales notatus, Brown bullhead Ictalurus nebulosus, Brown trout Salmo trutta, Burbot Lota lota, Channel catfish Ictalurus punctatus, Chinook salmon Oncorhynchus tshawytscha, Coho salmon Oncorhynchus kisutch, Chum salmon Oncorhynchus keta, Emerald shiner Notropis atherinoides, Freshwater drum Aplodinotus grunniens, Gizzard shad Dorosoma cepedianum, Grayling Thymallus thymallus, Haddock Gadus aeglefinus, Herring Clupea spp, Japanese flounder Paralichthys olivaceus, Largemouth bass Micropterus salmoides, Muskellunge Esox masquinongy, Pacific cod Gadus macrocephalus, Pike Esox lucius, Pink salmon Onchorhynchus gorbuscha, Pumpkinseed Lepomis gibbosus, Rainbow trout Oncorhynchus mykiss, Redhorse sucker Moxostoma spp, Rock bass Ambloplites rupestris, Rockling Onos mustelus, Round goby Neogobius melanostomus, Smallmouth bass Micropterus dolomieu, Sprat Sprattus spp, Turbot Scophthalmus maximus, Walleye Sander vitreus, White bass Morone chrysops, White perch Morone americana, Whitefish Coregonus spp, Yellow perch Perca flavescens.

APHIS has also released the Amended Federal Order Viral Hemorrhagic Septicemia (VHS) dated May 4, 2007. The purpose of this Federal Order is to prevent the spread of viral hemorrhagic septicemia (VHS) into aquaculture facilities. Also refer to the APHIS July 2006 Emerging Disease Notice – Viral Hemorrhagic Septicemia in the Great Lakes for further analysis.

Research reports published from the Scottish Fisheries Research Services may serve to provide management options:
Viral Haemorrhagic Septicaemia (VHS) – from the abstract:

Viral haemorrhagic septicaemia (VHS) was diagnosed inrainbow trout (Oncorhynchus mykiss) at a farm in Englandon 26 May 2006. VHS is a notifiable disease in the UK and a List II disease under European Directive 91/67/EEC. Investigations into the source and potential spread of the disease are being carried out by Centre for Environment, Fisheries and Aquaculture Science (Cefas) in England and Wales, and by Fisheries Research Services (FRS) in Scotland. VHS has occurred once before in the UK, in 1994, affecting a single turbot farm. The disease was successfully eradicated on that occasion. VHS has no implications for human health.

Risks to Wild Freshwater Fisheries from Viral Haemorrhagic Septicaemia (VHS) – from the abstract:

There is a risk of transfer of VHSV from farmed to wild freshwater fish species and vice versa. There is evidence that a reservoir of infection may be created in wild freshwater fish species. This may pose a risk of re-infection of farms (eg rainbow trout). There are no reports of VHSV infection leading to significant disease outbreaks in wild freshwater fish stocks. Based on evidence from outbreaks in farms and experimental evidence, free living rainbow trout, brown trout, whitefish, grayling and pike may be at risk of disease. Available evidence suggests a high infection pressure would be required to initiate a disease outbreak in wild fish (eg shedding of virus from an infected farm).

Disinfection guide version IV: practical steps to prevent the introduction and minimise transmission of diseases of fish – from the abstract:

Emerging diseases have had a significant impact on development of the Scottish aquaculture industry, highlighting the importance of preventing their introduction and minimising their transmission. The risk of disease spread is reduced by the implementation of good sanitary practices by fish farmers, and fisheries and the application of effluent disinfection systems in the processing industry. To maintain healthy fish stocks and minimise the introduction and spread of disease, the aquaculture industry should ensure best practice on farm sites, during transportation of live or dead fish and equipment, at the processing plant and during subsequent effluent and waste disposal. For an assessment of the risks associated with specific tasks, reference should be made to the Final Report of the Joint Government/ Industry Working Group on Infectious Salmon Anaemia (ISA) available from the Fisheries Research Services (FRS) web site, at www.frs-scotland.gov.uk. The protocols described in this guide are based upon current scientific knowledge and practical experience and will continue to be developed as the needs of industry change. This guide is intended for distribution to relevant industry personnel.

A new market has emerged for live black sea bass, Centropristis striata L., in fish markets of the northeast United States and Canada. Efforts to culture black sea bass have been hampered by the lack of information regarding optimal grow-out conditions. This research was designed to determine optimal commercial diet, feeding ration, temperature, and salinity for growth of hatchery-reared, juvenile black sea bass. Optimal diet was Zeigler Salmon Starter (compared to Nelson and Son’s Silver Cup Salmon Crumbles, Trout Crumbles, and Rangen Trout and Salmon Starter). Optimal daily feeding ration was 5% (compared to 2.5% and 7.5%). Optimal water temperature was 25º C (compared to 15º C, 20º C, and 30º C), and optimal salinity was 20 ppt or 30 ppt (compared to 10 ppt). Additionally, growth rates, feed conversion ratio, and mortality were calculated in each experiment. This information will be a valuable guide for culturing juvenile black sea bass.

The Marine Resources Research Institute notes that the first reported spawning of black sea bass occurred in 1884 with fish captured off South Carolina and shortly afterwards, ripe fish captured off Massachusetts were spawned. Since then there has been increasing information developed on the culture of this typical reef dwelling species. It is unclear if the 1884 date is correct. There is no doubt about the value of the species, and the, as yet undeveloped, potential for aquaculture.

Randal L. Walker and Deborah A. Moroney from the Shellfish Aquaculture Laboratory, Marine Extension Service, University of Georgia, USA; have published their findings entitled Growth of juvenile black sea bass, Centropristis striata, fed either a commercial salmon or trout diet. They observe:

An opportunity exists to expand Georgia’s commercial fishery by developing aquaculture techniques for the black sea bass, Centropristis striata. Black sea bass fillets sell for $1.25 to $1.50 per 0.45 kg wholesale. However, live, 0.9 to 1.13 kg fish are sold on the sushi market at a wholesale price of $3.50 to $8.00 per 0.45 kg. Little biological information exists concerning the culture of this potential aquaculture species. Six 600-L tanks on a flow-through system were stocked with 12 juvenile fish each (ranging in total length from 153 to 235 mm). Fish were pot-trapped from an offshore population. Tanks (3 for each diet) were randomly assigned a diet of either a commercial trout or salmon chow. Fish were fed a two percent daily ration (grams dry weight of food to grams wet weight of fish). Rations were adjusted biweekly to account for fish weight increases per treatment. Fish fed the salmon chow were significantly heavier after 10 weeks (P = 0.0209) and after 14 weeks (P = 0.0003) than fish fed the trout chow. Fish fed trout chow increased from 196 grams to 304 grams (55% increase) in 14 weeks, while fish fed the salmon chow increased from 163 grams to 386 grams (137% increase). Based upon fish growth and cost of feed, salmon chow is the preferred diet over trout chow for rearing black sea bass.

Again, from the Shellfish Aquaculture Laboratory, Marine Extension Service, University of Georgia, USA; Richard W. Kupfer, Dorset H. Hurley and Randal L. Walker have published their findings entitled A Comparison of Six Diets on the Growth of Black Sea Bass, Centropristis striata, in an Aquacultural Environment. The abstract notes:

Two studies of juvenile black sea bass, Centropristis striata, were conducted to address questions concerning the biological feasibility of aquaculture of C. striata. Juvenile C. striata and rock sea bass, C. philadelphica, were trapped inshore, while sub-adult C. striata were trapped in nearshore waters of coastal Georgia, south of Savannah. Catch composition of inshore trapping was dominated by Centropristis philadelphica (80%). Few C. striata were caught. A comparative growth study of juvenile C. philadelphica and C. striata fed a 3% daily ration (gram dry weight feed/gram wet weight of fish) was performed over 27 days. Overall juvenile C. striata mean increase in growth was 42% ± 5.3% (SE), with 10% mortality; whereas, C. philadelphica mean growth was 14% ± 4.7%, with 65% mortality.

Sub-adult C. striata (164 g mean weight ± 1.74) were subjected to six ration treatments for 18 weeks. Three replicate 500-L tanks were used per treatment, and each tank was stocked with 15 fish. Ration treatments consisted of a high-protein trout feed, a lower-protein trout feed, and an equal mixture of both delivered daily in rations of 2% and 3% dry weight feed/wet weight fish. All rations were adjusted biweekly based upon mean fish wet weight per treatment. At week 16, ANOVA revealed no significant differences (p=0.4096) in mean fish weight among treatments with a pooled treatment mean fish weight increase of 48%. Based on cost effectiveness, the lower-protein 2% ration was judged the optimum choice among the diets tested. This study reinforces the biological feasibility of rearing trapped C. striata on a commercial diet of 2% dry weight feed/wet weight fish.

Further, from the Shellfish Aquaculture Laboratory, Marine Extension Service, University of Georgia, USA; Alan Power, Tiffany Lee, Todd Recicar, Mary Sweeney-Reeves, and Randal L. Walker have published their findings entitled The Growth and survival of juvenile black sea bass, Centropristis striata, on an artificial (Salmon chow) versus a natural (grass shrimp) diet. The abstract notes:

This study examined growth and survival rates of juvenile black sea bass Centropristis striata (Linnaeus, 1758), that were fed two distinct dietary treatments, – one, a commercially available salmon chow and the other a diet consisting of natural live grass shrimp (Palaemonetes pugio, Holthuis, 1949). The diets were fed at a 2.5% ration (grams dry weight of food/ grams wet weight of fish). Fish were reared in replicated (N=3 per dietary treatment) 65-liter flow-through tanks for six weeks between May 7 and June 25, 2001. The fish provided with live shrimp had a mean survival of 69 ± 5.9% and increased in size from an initial mean wet weight of 20.7 grams to 30.4 grams – a growth rate of 0.194 grams per day. A higher mean survival of 80 ± 6.7% and a slightly lower growth rate of 0.184 grams per day (mean wet weight increase from 20.4 grams to 29.6 grams) were recorded for fish fed the salmon pellet diet. However, there were no statistically significant differences detected in either growth (p=0.7849) or percent survival (p=0.4999) between dietary treatments. Based on these results, we recommend using the commercially available salmon chow because of its convenience and supplementing it occasionally with grass shrimp to provide essential amino acids common in natural diets.

Lawrence W. McEachron, C.E. McCarty, and Robert R. Vega have reported on the Successful Enhancement of the Texas Red Drum (Sciaenops ocellatus) Population. From the abstract:

Red drum (Sciaenops ocellatus) is an estuarine-dependent sciaenid that inhabits estuaries, bays, and coastal regions from New York to Mexico. In Texas, the red drum population began a dramatic decline in the 1970s, prompting the Texas Parks and Wildlife Department (TPWD) to set up a three-pronged recovery plan. Management approaches were: 1) Initiate an independent monitoring program to assess relative abundance; 2) Implement restrictive regulations to reduce fishing pressure, including license restrictions, size, bag, and possession limits, a commercial quota, restrictions on netting, and a ban on commercial sale of red drum; and 3) Develop and start a marine enhancement program based on the release of hatchery-reared fingerlings and assessment of subsequent survival.

Recently, the red drum population in Texas coastal water rebounded because of several factors that had a positive effect on the recovery. TPWDs long-term management plan utilizing hatcheries and stocking to supplement natural spawning played a role in reversing the decline of the red drum population. The strategy used by the TPWD can serve as a blueprint for other marine enhancement programs.

The FAO have reported on Aquaculture Development of Red Drum (Sciaenops Ocellatus) in Martinique and the French West Indies. Note – the report is contained with other aquaculture reports on the page. From the summary:

The aquaculture of red drum (Sciaenops ocellatus) has been the subject of research and development work in Martinique since 1985. It was during the initial eight-year period that research findings showed the suitability of the species for domestication and mariculture.

However, whilst biological and technical knowledge is a compulsory prerequisite, it is not the only requirement for development. Operations throughout the production chain need to be synchronised, right through to product selling and company profitability. This explains the lengthy development process.

Since 2000, research reorganisation at IFREMER, the separation of larval rearing from growing-out, and the political and financial support of Martinique Region, have given a fresh impetus to our work, and development is now really taking off.

However, Martinique should not be the only island to benefit from this example; other Caribbean countries must also be given the opportunity to put the small-scale aquaculture model into practice.

Research into the culture of milkfish has not been limited to the Philippines. Research into the feasibility of milkfish culture in Fiji has been undertaken. Esteban Dela Cruz has published a report 1997, through the FAO, entitled, Potential of milkfish farming development in Fiji. From the summary:

Milkfish has been a successful food industry in Asian countries like Philippines, Taiwan, and Indonesia. The Government of Fiji had wanted to develop a similar industry, and so enlisted the help of the Food and Agriculture Organisation of the United Nations. The South Pacific Aquaculture Development Project (Phase II) devised this survey to ascertain the extent of the milkfish stocks in Fiji waters, and further to investigate the possibility of milkfish farming in Fiji. Such farms have already been established in Nauru, Kiribati and Tuvalu, and it was thought that milkfish farms would be not only a good source of protein for human diets and an alternative to depleting fish from the sea (and thus a way to ameliorate an environmental pressure), but also a source of income for villages and farmers as tuna bait as well.

There are many sites suitable to develop milkfish farms in Fiji, such as unused rice paddies, salt or prawn farms, or swamps and marshlands. Farmers need to acquire skills in preparing the ponds for stocking by draining, drying, leveling, and liming or poisoning for unwanted animals (where necessary). Also, dykes and water gates must be constructed and farmers must learn to feed the ponds to grow benthic algae (brackishwater ponds), and plankton (freshwater ponds). The design of the farms must take into account that milkfish swim against the current, so the catching ponds will be placed to concentrate fish from the grow-out ponds for easy harvesting.

The Fiji Islands Trade and Investment Bureau has published a report (2001) entitled Milkfish Farming Project Profile. This report outlines the investment potential of a milkfish project, including government incentives, and some forecast costs. Their summary of the market:

Market Milkfish is currently used as an intermediate good – an input – in the form of live baits for catching fish. Given the fact that milkfish baits supplements the longline tuna industry, which earns around F$40 million in export income, is indicative of the fact that there is a considerable market locally.

Prospective investors should do their own due diligence, and use the figures purely as indicators rather than current market realities.

Kee-Chai Chong, Ian R. Smith, and Maura S. Lizarondo have published, through the United Nations University (1982), a substantial paper entitled Economics of the Philippine Milkfish Resource System.

From the preface:

Considerable research has been conducted on milkfish in the Philippines. However, the available publications are scattered, and no attempt has been made in recent years to consolidate this information so that a concise appraisal can be made of the entire milkfish resource system, from fry gathering through dealers and nursery, rearing pond, and fishpen operators to marketing. The dual purpose of this paper is to provide such an overview of the Philippines milkfish resource system and to evaluate its efficiency.

The Aquaculture Center include some very detailed photographs of cobia, their husbandry, and background information.

Le Xan, from the Research Institute for Aquaculture No I, Vietnam; has published (via Simon Wilkinson, at enaca.org) a report entitled Advances in the seed production of Cobia in Vietnam. From the introduction:

Cobia Rachycentron canadum culture is expanding throughout the world, notably in China and Vietnam. Cobia have an extensive natural distribution, grow quickly, and can feed on artificial diets. Under culture conditions, Cobia can reach 3–4 kg in body weight in one year and 8–10 kg in two years. The products from Cobia are exported to the US, Taiwan Province of China and local markets. Market price of one-year farmed Cobia are around US$ 4–6 kg in Vietnam. Research on seed production and grow out culture of cobia in Vietnam began in 1997-1998.

The University of Texas at Austin Marine Science Institute began researching cobia around 1990. The Marine Science Institute reports that, “In April and May of 2001, cobia caught as juveniles two years earlier spawned naturally in a 9,000 gallon recirculating broodstock system at FAML. This is the first reported spawn of cobia raised from sub-adult to sexual maturity in a recirculating tank system using photoperiod and temperature cycles.” A more detailed elaboration of the research and outlines of cobia husbandry is also available.

There are increasing numbers of summaries and reports being published about cobia. Niels Svennevig, Head, of the International Projects Department, SINTEF Fisheries & Aquaculture, N-7465, Trondheim, Norway has published a summary entitled Farming of cobia or black kingfish (Rachycentron canadum). Houng-Yung Chen, from the Institute of Marine Biology, National Sun Yat-sen University, Taiwan, has published a brief summary discussing the use of low fishmeal feeds for cobia.

Research has also been conducted into the impact of cage farming cobia. Nazira Mejia Niño, from the University of Puerto Rico, has published a thesis submitted for a Master in Marine Sciences in Biological Oceanography, entitled Effects of Sustainable Offshore Cage Culture of Rachycentron canadum and Lutjanus analis on water quality and sediments in Puerto Rico. From the abstract:

This work was part of environmental impact study conducted from August 2002 until October 2003 related to two 3000m³-Ocean Spar submerged open-ocean growout cages stocked with Rachycentron canadum and Lutjanus analis south of the island of Culebra, Puerto Rico.

The principal objectives were to determine the local environmental effects of open-ocean submerged cage culture on water and sediment quality, as well as changes over time of some environmental quality parameters, including the feasibility of these operations on tropical marine waters.

Nutrient concentration (ammonia-N, nitrite-N, nitrate-N, and phosphate) were evaluated bimonthly in the column water and interstitial water at fifteen stations around the cage and three depths for the water samples; likewise, several water and sediment quality parameters were analyzed (dissolved oxygen, water temperature, turbidity, chlorophyll- a, salinity and organic matter). Water analyses indicated that, in general, both cages and the control site showed similar nutrients concentrations throughout the months analyzed. Ammonia was the nutrient with the highest concentration; however, these values were relatively low and normal for these waters.

Results of the first year indicate that this operation did not impact the quality of the water column, or the sediments even though large quantities of feed were introduced into the system. This was probably due to the large amounts of water flowing through the cages. The information obtained from this study provides a basis to evaluate the feasibility of this operation, encourages the open-ocean aquaculture industry.

Tetsuo Fujii and Masayuki Noguchi, from the Japan Sea National Fisheries Research Institute, have published a report entitled Interactions Between Released and Wild Japanese Flounder (Paralichthys olivaceus) on a Nursery Ground. The abstract:

The Japanese flounder, Paralichthys olivaceus, is one of the most important fishes in the coastal fisheries of Japan. But recently, overfishing has caused a reduction of the stock size. To enhance the stock, artificial seeds of Japanese flounder have been released. Interactions between released and wild flounder were examined to determine the success of the stocking program.

We performed experimental releases of artificial seeds in the shallow waters off Igarashi-Hama on the northwestern coast of Japan, from 1990 to 1992. The growth rate of wild flounder varied annually depending on the abundance of mysids that are the most important food for the flounder on the nursery ground. When mysids were less abundant, released flounder dispersed rapidly from the release site, ingested small amounts of food, and grew slowly compared with other years.

The feeding habits of released flounder differed from those of wild flounder when mysids were less abundant. Flounder released then ingested less food and also consumed gammarids which the wild flounder never ate. It was assumed that an abundance of mysids was more critical for released than for wild flounder. Further investigations on the carrying capacity of the nursery ground and improvement of the quality of artificial seeds are needed to enhance the stock size of Japanese flounder efficiently.

Nozomi Okada, Masaru Tanaka, and Masatomo Tagawa from the Division of Applied Biosciences, Graduate School of Agriculture,
Kyoto University, have published research entitled Bone development during metamorphosis of the Japanese flounder (Paralichthys olivaceus): differential responses to thyroid hormone. From the abstract:

The larvae of flatfish change their body structure during metamorphosis, including dramatic translocation of one of the eyes from one side of the body to the other. Such metamorphic processes are in general promoted by thyroid hormones (THs). This study focuses on the response of individual tissues to hormones, and morphological characteristics were examined in hormone-deficient larvae of the Japanese flounder (Paralichthys olivaceus).

Osamu Tominaga et al have published research entitled Daily Ration of Hatchery-Reared Japanese Flounder Paralichthys olivaceus as an Indicator of Release Place, Time and Fry Quality. In situ Direct Estimation and Possibility of New Methods by Stable Isotope. From the document:

Japanese flounder Paralichthys olivaceus is one of the most important target species of stock enhancement in Japan. The release size of hatchery-reared flounder is an important factor affecting survival after release. In order to improve the stocking effect of hatchery-reared juveniles, it is necessary to determine the optimum release place and time. Food availability for stocked juveniles is a key factor to evaluate the quality of release tactics. However, it is not easy to estimate the biomass of food organisms in the release area, because of the difficulty in quantitative sampling. Feeding intensity of released juveniles is affected by not only healthy condition of fish (vitality and nutritional status), but also physical, biological, and environmental conditions in the release area. Therefore, daily ration of fish after release becomes the useful tool to evaluate the release place, time and fry quality.

Aqua magazine (Chile) report some $45 million had been invested developing flounder farming in Chile using Japanese technology. The Japanese flounder had been introduced to Chile in 1997 via Hawaii.

Flounder offer some other interesting aspects from an aquaculture perspective. According to a summary of flounder information from the National Oceanic and Atmospheric Administration of the USA,

Flounder are naturally docile and not easily agitated. As a result, they subject themselves to little stress under farming conditions and, therefore, do better than more excitable species. They also like crowding together, though, as flatfish, they do not fully use the water column as do round fish such as large yellow croakers. In fact, stocking densities for flounder are usually expressed in terms of kilograms per square metre, rather than kilograms per cubic metre as they are for round fish. Optimum stocking density for flounder varies from 20 to 30 kg per square meter. This does not appear to stress them and, in this respect, they are similar to other farmed flatfish such as the European turbot and Atlantic halibut.

Flounders accept dry formulated feeds well and convert them efficiently, the feed conversion ratio (the weight of distributed feed per unit weight gain) being equal to 1:1 or a little more. This might be due to an intrinsic virtue of flounder metabolism and/or to a sedentary life style. If such excellent feeding efficiency could be achieved in large scale commercial systems, it would provide flounder farmers with a significant advantage from the economic point of view.

A number of academic researchers are working on developing techniques for consistent flounder management. Virginia Tech have also been working with Summer Flounder (Paralichthys dentatus), as well as Southern Flounder.

North Carolina State University researchers, lead by Dr. Harry Daniels, are working on establishing practical culture methods and defining nutritionally balanced diets for the mass rearing of weaned fingerlings and commercial-scale production of fish. The researchers have also produced a variety of resources related to flounder aquaculture. The research team have also experimented with increasing temperatures to promote the development of all-female cultured stocks. Studies have shown that female flounder grow two to three times larger than male flounder within two years – a worthwhile investment from a marketing perspective. According to this report, Japan leads the way in technology for producing farm-reared flounder. They are rewarded with a market price that more than doubles that of hybrid striped bass, tilapia or trout.

Aquanic have produced a document summarising the culture and potential of southern flounder. Southern flounder have a number of advantages, not the least of which is: “Because these flounder appear to grow well in low salinity water, growout operations could be located farther from high-priced coastal areas, reducing the fixed costs associated with flounder farming.”

The FAO have produced a detailed summary of the culture of seabass noting that Greece, Turkey, Italy, Spain, Croatia and Egypt are the biggest producers. Seabass are farmed in seawater ponds and lagoons, however the bulk of production comes from sea cage farming. The Mediterranean seabass industry, in less than 15 years, has grown from a few thousand tonnes to 57,000 tonnes today, peaking at nearly 71 000 tonnes in 2000. The United Nations Environment Programme Mediterranean Action Plan (Mariculture in the Mediterranean. MAP Technical Reports Series No. 140, UNEP/MAP, Athens, 2004) further underlines the importance of seabase as an aquacultural species.

Charles Cotton has published a research thesis entitled Optimizing Growth for Aquaculture of Juvenile Black Sea Bass Centropristis striata L. : Effects of Temperature, Salinity, Commercial Diet and Feeding Ration. Although the focus of the research is Black Sea Bass, the European Seabass in mentioned in context with grow out conditions.

Production statistics:
French production rose from an estimated 150 tonnes in 1993 to a peak of 980 tonnes in 1997; since then it has fluctuated, being 728 tonnes in 2002. In Portugal productions seems to be fluctuating around 350-390 tonnes/yr. By far the largest producer is Spain, whose annual production has nearly doubled since 1998. In 2002, Spanish turbot production was 3847 tonnes (75.9% of the global total). Besides the three countries mentioned above, no other country reported production above 50 tonnes in 2002.

The global production of turbot in 2002 was valued at US$ 41.38 million.

Market and trade:
Most farmed turbot is currently consumed in the producing countries. In Spain, about 75% of production is consumed internally; the rest is exported to France, Italy and Germany. The product is generally sold fresh and whole, though in France a small proportion of the production is sold gutted. The European turbot market has no specific regulations, and there are no limits on trade within EU countries, no minimum sizes, and no withdrawal price.

Status and trends:
Turbot aquaculture can currently be considered a mature technology. It seems likely that the industry will see marked expansion in the future, with the construction of new rearing units and augmentation of the capacity of existing farms. Nevertheless, continued research and development effort is required in the following areas:

* Fry production, with the aim of increasing larval survival rates.
* Improved culture systems and automation.
* Disease prevention and control.
* Stock monitoring and genetic improvement.
* Improved marketing, with the consolidation of existing markets and development of new markets.
* Avenues for processing need to be explored.
* Training for technical personnel with combined skills in aquaculture technology and business management.