You are right. Its growth rate is poor.

I think this discussion will be "all over the place" because fish are being cultured "all over the place" :-) . But contrary to terrestrial livestock, cows, pigs and poultry, which can be raised under a lot of different climatic conditions, fish cannot.

I started similar discussion in the LIFECYCLE aquaculture project forum on LinkedIn and even when I limited the question in geographic terms to Europe, we had a lot of species suggestions; warm-water and cold-water species, freshwater and marine, etc.

So I think the question really needs to be qualified in terms of environmental conditions, otherwise you'll simply end up with a long list of species, without really moving the discussion forward.

Thus, a more interesting question is e.g. what is the best species to culture in Nepal? I don't have any answer to that particular question, but others might. On the other hand, given that the snow trout is a coldwater species feeding on phytoplankton, its not surprising that it has a slow growth rate. In my mind, a interesting question is if it's an obligatory herbivorous species, or if it's like many other so-called herbivorous species, really an omnivorous species, which might then be able to utilize feed with higher energy content i.e. containing fat and protein and not just carbohydrates.

Hi again Bjorn,

You totally hit the point. I should have been more specific in my question. So, I will develop my thinking. Fish culture is becoming the biggest provider of protein for human consumption (if not already). According to Teletchea et al. (2012, in Fish and Fisheries), 85% of fish culture production in the world is given by only 15 species (carps, pangasius, tilapia, salmon, trout…). So my question is: to your opinion, what are the species other than these 15 that could enter in this hall of fame soon ? What are the species whose production will be more than let’s say 500 000 ton/year during the next decade or two decades ? Perhaps there is none. In any case please could you justify you answer (this question is addressed to everyone).

In Manipur, a Northeastern state of India, where aquatic vegetation is abundant and formulated feeds are non-existant due to poor connectivity, Grass carp is the most suitable species for aquaculture. In fact its a boon to the aquaculture of the State. Growth is much higher than IMC and other major carps in polyculture. However, quality fish seed is a problem with every farmer producing their own seed by hapa breeding without proper brood selection and management leading to inbreeding depression and slow growth.

Sihag, please see my answer to Bjorn: I'm talking about fish production that could aim 500 000 tons per year in a near future. I don't think there are so many. Gusheinzed, could you precise the scientific name of the carp you're talking about ?

Hello, I´m from Argentina, where is not well developed the Aquaculture, but I think Brasil has a big potential, and the others countries around with good climate and not well developed aquaculture potential has the power to became a good producers (Colombia and Ecuador). So they can enter in this top 15 with his species, becouse we are working hard to develop native species like Colossoma and Pseudoplatistoma, those two has good growth and realy good taste and aceptance. Other one is the Arapaima growth realy fast but need a lot of development. And arround the world im locking with some interest the CHANOS specie (becouse the feeding habits) and the Rachicentrum canadum ( fast growth but realy fast). But I think this tropical American countries can only growth in his production , so I vote for Colosoma, Pseudoplatistoma or another cat fish from this latitudes.

There are two principal ways in which aquaculture can/will expand in the future.

One is through increased production of already established species - as Neil pointed out, a very large part of the aquaculture production is based on about 15 species. There are, of course, logical reasons for why this is so. One is that these are well-known (for the consumers) species with large markets, and they've proven to be relatively easy to raise in aquaculture. The large, often multinational, aquaculture companies are strongly in favor of increased production of established species for several reasons. One is that the markets for these species are already there, and as long as the demand is high enough, it's possible to increase production. The increased production of these established species is best served with research into domestication and breeding-selection programs, because fundamental traits such as growth rate have very high heritability so that growth rate can be significantly improved from generation to generation, sometimes as much as 30% per generation! Presently (2009 figures), there are about 37 breeding selection programs on 14 species in Europe and probably well over 100 programs world-wide.

The other principal way of increasing aquaculture production is through species diversification, and this is the basis for Neil's question. The reason for why most of the major producers are reluctant to follow this path is that it's hugely expensive to develop a new species for aquaculture, just as it is expensive to develop a new drug or a car model, and the track record shows that 9 out of 10 species tested in aquaculture fail. You need research to solve problems with reproduction and larval development, feed and nutrition, stress, welfare and pathology etc, etc. Norway has e.g. over the last two decades probably spent at least one billion US $ on the development of halibut aquaculture and then cod aquaculture and both still remain as low-production, niche species. This is not all bad as it also indicates the way for smaller producers to pick up "new" species, which have perhaps have not been successful in large-scale, intensive, industrial aquaculture, but may fit much better as a local, niche production species for the smaller fish farmer.

Cheers, Thrandur

Indian Major carps, Tilapia, Thai Pangus are the most promising fish species for aquaculture in Bangladesh. Indian Major Carps have high consumer preference and can be utilized in polyculture which is particularly practiced in Bangladesh. They grow comparatively faster, disease resistant. On the other hand, Tilapia and Thai Pangus are very fast growing and now becoming very popular due to their taste and low market price. There are some shrimp species also promising particularly in the southern part of Bangladesh such as M. rossebergii, P. monodon etc and also some crab species are now cultured to some extent.

I thank that, it depends on your country. For Egypt Marine culture species such as sea bass, sea bream and meagre. While in fresh water African catfish, silver carp,common carp and grey mullets.

More opinions: http://grist.org/food/miracle-fish-is-the-search-for-the-perfect-farmed-seafood-really-over/

In Romania, the most popular fish species are Common and Chinese Carp. Since 2000 trout become a trend, because of the international market demand and economic and quality value. Sturgeons are also an interested fish species, a lot of enterprises apply for European Fishery Funds and they are in process of developing new intensive rearing systems. I hope they will be successful and Danube sturgeons will be appreciated both for meet and caviar!! Each country have specific environmental conditions and a market demand. Advertising is very expensive and to introduce a new fish species on the market without an aggressive advertising is a high risk.

Anyway aquaculture is the best solution for protein production. Don't forget that our planet is mostly water..and water is the rearing environment for fish production. I think is not so important what new fish species we are able to introduce on the market, but is important to produce as much as possible to cover protein needs of the Planet!!

It will depend on region and market. In Indonesia, I could say tilapia and carp is the most promising in freshwater culture; Penaeus vanamei and monodon are the great cultured species in brackishwater and grouper in marine culture. However, for domestication and diversification, catfish species is very promising in freshwater, and mussel and oyster for marine cultured. The demand for those species is increasing.

In Australia Sleepy Cod (Oxyeleotris lineolata) and Barcoo Grunter (Scortum Barco), commonly retailed as Jade Perch, are very promising freshwater aquaculture species. Both species are relatively hardy, fast growing and have good eating qualities. Barcoo Grunter also offer extremely high omega 3 levels. Markets are already developing for both species. Sleepy Cod could be used to replace the Australian market for Marble Goby which is a popular species in Asia.

Elsewhere in the world as largely already mentioned Carp spp, Tilapia spp and large Catfish spp. These species are all hardy, fast growing and marketable in Asian countries.

It is obvious the fish groups in the lower food chain. The major carps are the most important groups which could be thought of future fish culture. Next the chinese carps followed by Thai catfish Pangassius. If you could feed the catfish with wastes like chiken waste, beef wastes etc., african catfish can be the right choice. Though genetic based breeding and growth protocol are followed in salmonid culture,that may not be a better choice. Because in future, we cant feed the fish with animal meal. Finally the cichlid, tilapia could be the right choice because of it could be cultured intensively with biofloc technology.

If the main motto is to make money, think of carnivores group and if you are interested to feed the mass go for herbivorous fish group for culture.

To me, it's strange when people such as Paulraj above suggest that we breed herbivorous species and a the same time suggest that these species should be fed chicken and beef offal. It underlines the fact that these species are not really herbivorous, but omnivorous, and if we want them to grow fast, we feed them the same animal proteins as we feed our carnivorous fish species. Thus, the aquaculture operations in e.g. Vietnam are cleaning up the Mecong and coastal areas of small pelagic fish to feed the Pangasius! Even if Greenpeace has been politically forced into giving a small percentage of these operations an ASC certification as being sustainable, the majority of them are definitely not.

The comment about being able to choose between making money or feeding the masses may sound good, but to me it really doesn't make sense. All food production needs to be economically sustainable.

The question "which is the most PROMISING species" must be regarded also from a socio-economic point of view: most promising to whom? The answer may be different if the fish farmer is a large corporation, a local bigwig, local small farmers or fishermen? A species "promising" to the first would not necessarily by the most advantageous to the others, and vice versa.

IMO, basically, the species chosen for breeding would depend on the combination of the following: (1) demand (which depends on local preferences and retail prices) , (2) the price and availability of, and ideological approach (animal or vegetable) to the sort of feeds needed, (3) the locally available technology, investment level and subsequent production costs, (4) availability and cost of space, water and energy), (5) socially environmental sustainability constraints (e.g., where fish farms dislocate small farmers and fishermen or replace mangrove areas), and obviously (6) general environmental conditions, such as climate, water temperature and quality, predators, pH level in earthen ponds, etc.

I apologize for complicating things, but as we all know there're plenty of simple (and wrong) answers. MB-Y

By "promising", I meant "promising for feeding a vast community" (at least dozens of millions of people). In other word, a production that would reach at least 500 000 tons in a near future (e.g. 5-10 years). All the points you highlight are indeed implied within that question and are to be taken into consideration in the argumentation. My question addresses in fact those species whose breeding has been proven feasible and that are currently under increasing production. For exemple, Pangasianodon hypophthalmus could have been predicted as a "promising species" ten years ago (its production increased from 100 000 tons to 1 000 000 tons within 10 years). Do we have similar expectations for other species at the moment ?

Well, in warm climate and waters, I'd think that the tilapias are species for mass and not-expensive production. Some tilapias are adapting well to low quality and saline waters. Common carps are another example fitting cooler waters. Both sorts can thrive in poly-culture ponds, where water temperature doesn't fall below, say 12-15 deg.C.

Mass production, assuming that there's mass demand at low-price levels, depends very much on the availability of feeds at low-level cost. A suitable infrastructure, usually government supported, such as hatcheries, veterinary supervision and care, and farmers training represent an important factor in any mass production. MB-Y

Dear Wang

Happy to have a good discussion on which species suited for aquaculture in our geographical area. The Indian region is a tropical one. Here we are having over 2500 species and we hardly culture 10 species in freshwater fish aquaculture system and one or two freshwater prawn varieties. The famous Indian major carps are cultured in most of the region along with Chinese carps and common carp. Here we are having mostly three species combination poly-culture like Indian major carp or six species poly-culture system like catla, rohu, mrigal, grass, silver and common carp. In some parts the Pangassius culture is picking up. Already exotic African catfish has been introduced in some parts of south India and due to its entry into wild, it has been banned. and two or three shrimp species

Initiations has been taken for culture of Indian minor carps like Cirrhinus, Labeo and Puntius. But all are in experimental scale.

While in coastal regions shrimps are mainly culture. Apart from monodon now vannamei is picking up. Of course with so many problems like white spot.

In my view culture of tilapia found to be the future and new initiatives has been taken by our institute using biofloc technology and genetic improvement.

Our major carps require more space for growth and not adapting to formulated diet. The price also not lucrative. They need a lot of research on intensification. Some farmers dont want to work hard. So they go for general extensive poly culture system. In Andhra Pradesh, a state in India, where carp culture activity is very good, could get a production more than 15 t per ha. Since the farm gate price is not lucrative for carps, our people are very much interested to go for diversification like tilapia and pangssius.

The later is picking up, due to fast growth and omnivorous feeding habit.

But in my view, scientific interventions are needed to enhance the production .

As for as coastal farming is concerned, the seaweed culture is coming up particularly Kappaphycus alvarezii. The vast see is our feature hope for expansion. In our college initiative has been started along with leading Indian Institutes, about farming Cobia. It is good. Again feed conversion rate. The scientist has to think positively on regional group of fishes so that the malnutrition and protein related issues can be addressed efficiently.

But it is a long way to go.

Dear Björn,

already >10% of Vietnamese Pangasius exports are ASC or Global GAP certified . The industry and vietnamese government declared that they will reach 80% in 2015. So in my opinion this could be a great success story how to cultivate a low trophic level species on an industrial mass scale while minimizing ecological impacts.

But we will see the final results in 5-10 years.......

By the Way the ASC was initiated by the WWF, Greenpeace somewhat opposes the ASC standard because it allows GMO soy as feed ingredient.

Menakhem explained the possibility of culturing Pangasius and tilapia. In my view also these two could be the promising species. As Carmen Popa indicated common carps and silver carps could be cultivated in colder regions. All these groups are fast growing and can be grown on intensive scale. I am recently hearing about cultivation o fSleepy Cod (Oxyeleotris lineolata) and Barcoo Grunter (Scortum Barco), I understand that feeding the first two groups Pangassius (Pangasianodon hypophthalmus) tilapia along with common carp could be possible due to their omnivorous nature and possiblily of growing under intensive units with biofloc based culture. The silvercarp are planktivores and its intensification may be questionable.

In my earlier answer I indicated the culture of african catfish with wastes generated from poultry waste. In our place the waste generated from poultry ,particularly the intestine, head and legs, were used directly to feed these fishes. As they are voracious feeder and grow faster, the waste generated from these places form as a low cost supplement instead of costly protein rich feed pellets. Since it created a lot of problem in Tamilnadu, like odour and disease, cultivation of this group is banned. The escaped fish to the environment also creating so many problems including fish diversity loss.

I must be thankful to Wang, Björn Thrandur Björnsson and Menakhem Ben-Yami for thinking the future candidate species for aquaculture which is ecofriendly and economically viable.

Finally I wish to widen the discussion about the need of improved husbandry practises and its role on improving the production from these group of fishes. We have extensive systems like poly culture of carps. Through this system we can get a production upto a maximum of 10t/ha per year. Modern and affortable technological improvement are implemented so that the FAO recommended level of protein consumption could be partially supplemented through fish culture.

In my region of the world, Clarias gariepinus (the African catfish) is the most successful aquaculture fish because various aspects for its survival and reproduction are clearly understood. It is the most reproductively manipulated species with table sized fish being produced within a short time. Although it doesn have the best of tastes when it is cooked, but it constitutes a major source of protein in Africa.

On the other hand the tilapias particularly O. niloticus is a very important domesticated fish spanning various ecological ranges because it is omnivorous i.e. it can adapt to any feeding regime depending on the environment it finds itself.

Dear Björn:

Thanks for the question. I agree the answer depends on the region and even on the country (considering the social, economic and political stabilties and characteristics).

My input will be from the side of Chile.

Chile is a country with a tradition of well managed fisheries and aquaculture. In countries with this kind of fish cultivation culture, the "promising species" should be the endemics ones specific for that country.

Chilean salmon industry will probably achieve the highest level of sustainable production in a few years and won´t be able to produce more salmon (unless offshore). Knowing this reality, a few years ago (2009) the Chilean government, universities and the aquaculture industry are promoting the use of endemic chilean species such as palometa (Seriola lalandi), corvina (Cilus gilberti), deep-sea cod (Dissosticus eleginoides) and merluza austral (Merluccius australis), among others. Results are promising and it is expected that big aquaculture production systems and farm for these species will be achieved within 5 years.

Cheers

Hernan

Hi Herman,

Chile has fantastic possibilities as an aquaculture nation and I think it's very wise, not least based on the recent problems in the salmon industry, to diversify the aquaculture to new, marine species. I also absolutely agree with you that the focus should be on endemic, local species.

You certainly list a few interesting species, and the most recent EU funding initiatives for aquaculture diversification will include research on Seriola species.

During my recent visit in Chile, I had very nice Congrio dorado and I think these Genypterus species could be an interesting alternative. Our current research collaboration with Chile focuses on the fine flounder (Paralichthys adspersus), which is one of the most expensive fish on the Chilean market. It does suffer from unusually slow growth rate which is an extremely interesting research topic in itself. Understanding why some species grow fast and some grow slow, even under similar nutritional and environmental conditions, can hold the key to finding the most promising future aquaculture species. I attach our recent research on the fine flounder or the Chilean flounder as it is also called:

Article Nutritional status modulates plasma leptin, AMPK and TOR act...

...and this...

Article Plasma leptin and growth hormone levels in the fine flounder...

...and this.

Article Inherent Growth Hormone Resistance in the Skeletal Muscle of...

Carps & shrimps

Fresh water pearls too. As they are biological controllers and do not threat to other species

Thanks for the papers, Bjorn. It is a fascinating topic to talk about and wonder about the future of aquaculture, as it will be the one animal production, that will feed animal protein the world in the near future.

Dear Hernan. You're welcome to the papers. We'll be continuing our collaborative work on the fine flounder between the team at Andreas Bello, Santiago, and our group in Gothenburg in the fall with a new project.

What about the pictured species for Chilean aquaculture? I tasted great, straight off the fishing boat!

carps are proliferic breeders , possess high fecudity, growth rate, less bone to flesh ration better preservation period and quality food after preservation and easy to culture in freshwaters. similarly, pearls have better stocking densities per unit area, better growth rates and highly economical of view points that every part of its body is useful to human consumption as food, ornaments and basic drugs. Thus, carps & pearls mussels are sustainable and most promising species of the freshwater aquaculture.

An export oriented fish will be dominating the aquaculture's future. in this regard my choice is Cobia as it has promising growth rate around 4-8kg per year from 21 degree Celsius to 33 degree celsius

An export oriented fish will be dominating the aquaculture's future. in this regard my choice is Cobia as it has promising growth rate around 4-8kg per year irrespective of the temperature i.e, from 21 degree Celsius to 33 degree celsius the above said growth has been witnessed

Can you please give me the biological details of this fish species.

I vouch for herbivores because we dont rely much on fish meal whcih is again a demanding input that puts pressure on wild-caught low-value fish. Primary production in the water body is much easier and the use of plant by-products as feed ingredients is much more environment friendly. Also the age-old practice of multi-tier cultivation using different natural feeding habits that depend on the primary produces and grazers.

That's right, however, the problem comes up when or where a fish farmer can obtain fishmeal that's cheaper than soya meal or similar concentrated feeds. And sometimes it is. MB-Y

Jose could you kindly upload a copy of the paper or mail me on [email protected]. I'll be grateful.

THanks

Fish and Freshwater Crustaceans

A. Cultured Commercially

1. Rainbow, brown, and brook trout (Oncorhynchusmykiss, Salmo trutta and Salvelinus fontinalis, respective-ly) are cold water fish which require well oxygenated wa- ter below 65°F. They are cultured commercially in manynortheastern states. Pennsylvania and New York are the leading producers in the region.Most trout are grown in flow-through systems; al- though some culturists currently reuse their water and a few use cages or net pens, Rainbow trout are marketed for stocking and as food fish. Brown and brook trout are stocked for recreational fishing; some are also sold as food fish.

2. Atlantic salmon (Salmo salar)

are native to the east-ern United States and better suited to aquiculture condi- tions than their Pacific coast relatives. The Atlantic sal- mon has become an important aquaculture species. Most commercial aquiculture in the Northeast is located in New England, particularly Maine. Atlantic salmon are released as smelts in streams to enhance natural populations and cultured in cages or net pens placed in areas with substantial flushing. Smelts may be produced in freshwater hatcheries or purchased.

3. Fathead minnow s

(Pimephales promelas are the most important live bait produced in the region. They are usually raised in ponds. Culture ponds are typically ferti- lized with a vegetable material such as soybean meal or wheat sorts which stimulates the growth of algae. The re- resultant plankton bloom is eaten by the fish. Some growers use a low protein, commercial fish feed. Potential markets exist for fathead minnows as bioassay and research ani- mals.

4. Channel catfish (Ictalurus punctatus)

are the most important fish currently cultured in the United States. Both fingerlings and feeds are commercially available. Most channel catfish are raised in the southern United States in ponds one-half to ten acres in size. Cage and net pen culture are also practiced. In an existing pond, cage culture represents one way for those considering fish farming to try their hand at fish culture with a minimal cash investment. Catfish can survive a wide range of temperatures and will tolerate brackish water. Commercial culture in the Northeast may be limited to the mid-Atlantic region be- cause catfish grow best above 80°F. Throughout much of the Northeast the culture season is too short for commer- cial success.

5. Striped bass (Morone saxatilis) and its hybrids (M.saxatilis x M sp.)

have recently been cultured commer-cially. They are raised as striped bass or, more common-

ly, hybridized with other fish in the genus Morone suchas the white bass (M. chrysops), white perch (M. ameri-cana), or yellow bass (M. mississippiensis). The mostcommonly cultured fish are the female striped bass x malewhite bass hybrid (also known as the Palmetto Bass) andthe reciprocal cross, female white bass x male striped bass(also known as the Sunshine Bass). Hybrids usually havea deeper body, shorter tail, and more sloped head than thestriped bass.Striped bass and its hybrids tolerate a wide range oftemperatures and salinities, from fresh to salt water. Theyare a warm water species and grow best at 75-83° F. Thelength of the growing season is one factor that determineswhere they can be raised profitably.Striped bass and its hybrids are cultured commerciallyin ponds, flow-through systems, and cages. Work is beingdone with culture in recirculating systems. Striped and hy-brid bass culture are still in development and many ques-

tions require additional research.

6. Goldfish (Carassius auratus)

commonly cultured in small ponds or tanks. Because of their high value, recirculating systems have commercial potential. Outdoor culture units maybe covered in winter to protectt fish from the cold. Ornamentals are marketed live so surrival in transport is very important. The market is highly competitive and well established.

7. Several species of gamefish are cultured commer- cially in the northeastern United States. Included in this group are sunfish (Lepomis sp.), black bass (Micropterus sp.), walleye (Stizostedion vitreum),

yellow perch (Perca flvescens), trout, and Alantic salmon. Culture methods vary considerably between species. In most cases the fish fanner purchases or hatches eggs and rears the fry to fin-gerling size. Fingerlings are then sold and stocked for rec-reation; some are rearedred in growout operations for market. Fingerling sunfish, bass, and walleye are normally produced in ponds, while fingerling salmonids (trout and salmon) are produced in raceways or tanks. Culture proce- dures for some species such as bass, sunfish, trout, and salmon are better known than for others, such as walleye and yellow perch.

8. Crawfish Orconectes sp. and Procambarus sp.)

Are crustaceans; they represent a significant aquiculture in- dustry with substantial growth potential in the Northeast. Most culture occurs in small, shallow ponds where the an- imals feed on natural vegetation that maybe supplement- ed with hay or other grain by-products. Though more cor- rectly characterized as a shellfish, crawfish are grown in concert with minnows. In New York, for instance, craw- fish are raised with fathead minnows and marketed as bait. Crawfish may be harvested with traps or a seine. Procambarus are cultured in the mid-Atlantic region as a human food for local markets. Several species of Or- conectes are grown in the Northeast. Some potential ex- ists to market these as human food, particularly in Europe. Orconectes more closely resembles the traditional “noble crayfish” (Astacus astacus) and are more readily accepted by European consumers than the red swamp crawfish (F’. clarkii) and the white river crawfish (P. zonangulus).

B. Potential Commercial Species:

1. Tilapia (Tilapia sp.)

have been cultured commer- cially in the United States. They are hardy, grow rapidly, and are acceptable, though not well known to consumers. Tilapia are tropical fish and require warm water to sur- vive. If water temperatures fall below approximately 50- 55° F, they will die. In this region, most

Tilapia culture

has occurred in ponds during summer or in heated units such as recirculating systems. Commercial culture in the Northeast has not been demonstrated on a sustained ba- sis.

2. Golden shiners (Notemigonus crysoleucas)

are the mainstay of the live-bait industry in Arkansas, although some are cultured commercially in the Northeast. Usual- ly cultured in ponds, golden shiners are less hardy than the fathead minnow. In much of the Northeast, they re- quire two growing seasons in order to reproduce. How- ever, the golden shiner is more appealing to the angler and attains a larger size than the fathead minnow.

3. White suckers (Catostomus commersoni)

are carpcltured during their spring spawning run by some bait pro- ducers in the Northeast. Eggs are striped and incubated; hatched fry are reared in ponds. Suckers grow faster than golden shiners and in one growing season attain a size desired by bass and pike anglers. Market size and culture details require further research.

4. Bullhead (Ameiurus sp.) are a popular recreational and food fish in the Great Lakes basin. Experimental work indicates that black bullhead (A. melas) Survives and grows well in ponds or cages. They do best in turbid waters. Farmers are growing and marketing bullhead in upstate New York, but the economics are inconclusive.

5. Carp (Cyprinus carpio),

an important finfish in the world, has minimal but growing demand in the United States. Technology to culture carp in ponds is well known and the fish is suited to conditions throughout the Northeast. The principal obstacle is poor consumer ac- ceptance. Carp could provide a dependable supply of fish for use in value-added products such as surimi and fish sausage.

6. Grass carp or White amur (Ctenopharyngodon idella)

are occasionally stocked in ponds to control aquatic vegetation. The sterile triploid is most commonly used. The fish survives well and grows rapidly. Laws regulating its importation and use vary between states. Culturists should consult their Department of Natural Re- sources or its equivalent before stocking fish.

C. Experimental Species

1. Walleye are prized throughout the northern United States as a premier food fish. Fingerlings can be trained to accept pelleted food, but the procedure requires spe-cial skills. A few growers are producing walleyes in ponds and cages. Most are marketed as advanced finger-

2 lings, although some are sold as food fish. Growers in the northeastern United States could benefit from advances in walleye culture.

2. Yellow perch are extremely popular food fish in the northern United States. They are hardy, can be trained to accept pelleted feeds, and are grown in a variety of sys- tems such as single-pass and recirculating systems. At present neither the technology nor the economics of their culture beyond fingerling stage have been adequately de- veloped. 3. Recently, significant advances have occurred in the culture of sturgeon (Acipenser sp.). White sturgeon (A. transmontanus) are now being raised and sold by western producers. They are typically marketed at 8-12 pounds as food. Other potential markets include roe as caviar and small fingerlings for the aquarium trade. The culture tech- nology has not yet been transferred to other geographic areas or to other sturgeon species.

4. Arctic char (Salvelinus alpinus)

are an attractive, hardy, and rapid growing relative of the brook and lake trout. Arctic char tolerate cold temperatures and grow best below 50°F. They have been grown successfully in flow- through, cage and net pen systems that use marine or fresh water. Limited availability of fingerlings, regulatory problems, and lack of marketing information are major constraints.

5. Prawns and shrimp (Macrobrachium sp.and Penae-us sp.)

are subtropical crustaceans that do not survive when water temperatures fall below approximately 55°F.

Post larval Macrobrachium are grown in fresh water pen- aeids are cultured in brackish water. In the Northeast their culture potential is limited and the technology has not been adequately demonstrated. Those interested in the culture of these crustaceans should consider crawfish cul ture as a more likely alternative.

6. Several species of marine finish are~ being viewed as potential aquaculture candidates. Included in this group are halibut (Pleuronectidae), cod (Gadidae), turbot (Pleu-ronectidae), and flounder

(Bothidae and Pleuronectidae). Many problems exist and culture techniques need further development before these fish can be considered for com- mercial aquacultyre. Shellfish

A. Cultured Commercially

1. Northern quahog or Hard clams (Mercenaria mer-cenaria) Are one of the most widely cultivated molluscs in the region. An established market exists and the product is

recognized

as a moderate to high priced item in the res- taurant trade. The smallest, legally marketable clams bring the highest price. They are hardy and have been cul- tivated successfully throughout the region. The best results have been achieved in coastal waters off Massachusetts and south to Florida. Adult clams are spawned under controlled conditions. Larvae are fed a specially prepared algal diet and raised in land-based up- wellers, tanks, or raceways. The nursery phase can be on land or in the water. Spat or seed are stocked on the bottom in coastal wa- ters and grown to market size. Time to market size is ex- tremely site specific. Typically it takes three to five years to attain this size, but with improved strains, a preferred site, and good management culture time can be reduced.

2. Eastern oysters (Crassostrea virginica)

have been cultured in the Northeast for over 100 years and are grown commercially throughout the eastern United States, including the Gulf Coast. Techniques through the nursery phase are well-documented. Oyster seed or eyed larvae maybe purchased and *’set” on appropriate sub- strate. Oysters may be cultured directly on the bottom or in racks off the bottom. Management includes predator cent.ml, grading, and cleaning. Good water flow is essen tial. The greatest impediments to oyster culture are dis- ease, restrictive laws, and regulations (Federal, State, lo- cal, etc.). Prospective culturists should thoroughly research sites that they are considering.

3. Blue mussels (Mytilus edulis)

are increasingly pop ular. Through aggressive marketing in the early 1980s, the demand and retail price for mussels has improved steadily. Therer is no hatchery phase for commercial culti- vation. Seed is collected from nature and replanted on the bottom at a density much lower than that found in natural beds, or placed in long mesh sleeves suspended in the wa- ter column. Most mussels are cultured in Maine.

B. Potential Commercial Species

1. Soft clams or Softshells (Mya arenaria)

can be pro- oduced in large numbers by using hatchery techniques. Al- though the market is strong for steamed or fried product, little work has been done to develop effective growout methods. A relatively low price when compared to other bivalves has contributed to this neglect. Maine is current- ly culturing soft clams for restocking in public waters. Al- though used successfully in stock enhancement, the po- tential for commercial cultivation of soft clams is not considered promising at this time.

2. Bay scallops (Argopecten irradians)

can be cul tured in the hatchery or obtained from the wild. However, relatively little attention has been directed to their culture. The scallop can move, so containing them is a challenge. Lantern nets have been used to culture scallops in the Ori- ent, but similar efforts in the United States have proven too labor intensive for commercial success. Markets exist for a half-shell product in upscale restaurants, although the demand currently appears small. Prospective cultur- ists should carefully assess the management and econom- ics of scallop culture before proceeding.

3. Blue crabs (Callinectes sapidus)

for steaming have long been popular in the marketplace. Their abundance in coastal waters south of Long Island provides sufficient numbers to meet market demand and reduces the need for culture. However, a market exists for “soft shell” crabs which occur immediately after a molt and are considered a delicacy. Crabs with body marks indicating an imminent molt are collected from nature and held in shallow tanks until they emerge from their shell. These shedding sys- tems are fairly simple and the potential for commercial success is good, provided an adequate supply of high quality and reasonably priced crabs is available.

C. Experimental Species

1. Atlantic clams or Surfclams (Spisula solidissimia)

are being cultured experimentally in Maine. Hatchery seed and hard clam growout technology are being used. The project is on-going and, at this time, it is unclear how or whether techniques can be applied commercially.

2. American lobster (Homarus americanus)

are often regarded as animals with great potential for aquiculture because of their high price. Lobsters have been cultured only to a juvenile stage for release to nature. Public hatch- eries are operated for enhancement stocking. Private at- tempts at culture are not recommended at this ti

What you're describing are some of the currently aquacultured species in the USA, which is not really what this question is all about. Although I understand the logic of the currently cultured species being the most "promising" (otherwise they wouldn't be cultured), what I'm asking is rather directed towards the future - which "new" species should we bring into aquaculture in the future?

It has been estimated that there are about 200 species that have been trialled for aquaculture in Australia, but despite the enthusiasm of the proponents, most are not commercially viable. Growing "new" species is easy, the economics of marketing aquatic organisms is complex and involves not simply “maximum market price” but also quantity and consistency of supply. Nobody wants 10 tonnes every 12 months, they need 10 tonnes a week, 52 weeks a year and price reflects that.

The most successful aquaculture species (seaweeds, molluscs, crustaceans, amphibians and finfish) are probably pretty much known, but there is a lot still to do with genetics and domestication. F3 Pagrus can be fed by hand, for example. The other “elephant in the room” is disease. I estimate that world aquaculture production would possibly double without any increase in infrastructure or feed consumption if there were no losses due to diseases prior to harvest.

How about anchovies? Considering the most abundant species but also the most consumed one around the world.

Yalcin, I don't believe one can grow anchovies at a price that can compete with that of captured anchovy. When you think of perpective species for farming, you must start with the eventual market price: whether you can produce your species cheap enough to compete on the market, and make some extra money for profit, insurance, and for surviving unexpected problems (epidemics, poisoning, etc.) once in a few years. MB-Y

Menakhem, the question is not for today but which "new" species should we bring into aquaculture in the future? So we shouln't consider the current market . I believe in the near future we will have decreased natural stocks of anchovies because of pollution, global warming etc. And decreased stocks push the market prices up. So if we try to find most promising species in the future, I think we need to start with most demanding ones first. We sure will have some problems initially like adaptation and diseases but try to find best management practices. Regards Y.T.

G'd luck, Y.T. MB-Y

Recent changes and global trends. More specifically, you will culture of species such as barramundi, cobia, dolphin fish, spiny lobsters, slipper lobsters, mud crabs, penaeid prawns, Nile tilapia, yellow king fish, abalone, sea cucumber and sea urchin, seaweed, ornamentals and Indian major carps, fugu, mud skippers, cephalopods and blue fin tuna.

Mr.A.K.

What about the economic of the culture you are suggesting . I think FCR is the basis of the dependability of the species to determine the suitability for the culture practices. few other parameters are too required to make it suitable for culture. i think only tilapia is the species useful in the world aquaculture scenario. I endorse the points raised by MD-Y on the issue.

Ashok Verma