The Mission had as one of its objectives the appraisal of the future role of aquaculture in the Caribbean islands. The economic viability and social relevance of aquaculture here as elsewhere, is determined by: government objectives, manpower, and other factors of production essential for aquaculture projects, and by the physical environment. The geographical and climatic similarities amongst the islands, so obvious to the traveller, hide economic and cultural differences. These are important to economic viability and social relevance. Thus, from its short visit to the area the Mission can no more than formulate suggestions for what might be the future role of aquaculture in the islands, and suggests actions that island governments might take to define more clearly how to develop aquaculture.
From the point of view of aquaculture development the situation of the Greater Antilles does not appear to be very special or different from continental countries at corresponding latitudes and therefore in what follows, detailed discussions will relate largely to the smaller islands.
There is little ongoing commercial aquaculture in the region if the islands visited are typical; there are exceptions, the foremost of which would seem to be Cuba. Efforts to develop aquaculture are underway, however, in several islands. In keeping with the scarcity of resources available, the effort is small. The exception is Jamaica where development of inland fish culture is receiving massive government support. Annex 10 contains a list of aquaculture development activities in countries visited by the Mission. The projects listed for countries that the Mission did not visit are compiled on the basis of information collected.
In its review of the Caribbean in Chapter 2 of this report, the Mission discussed some factors of special importance for aquaculture development. The observations made in that section were confirmed during the visit. In addition the Mission noted some further constraints to aquaculture development. They are related to biological information, legal aspects, infrastructure and information exchange.
There is a lack of biological information on many aspects relating to aquaculture. Life histories of most local species have not been sufficiently studied. Little is known of the availability of seed stock from the wild. The same applies to physiological tolerance of culturable species to environmental variables. More basic studies are needed.
As is noted, there has been little attention paid to devising a legal framework conducive to aquaculture development. In some countries visited there are no rights to fresh water. Most of the marine and brackish waters, as well as submerged lands, belong to the State and cannot be privately owned. Provisions for leasing such areas are usually vague as is the right to exclusive use. How to enforce restrictions in areas long subject to common use is a problem. Some countries have restrictions on minimum size of fish, or gear, which would at present prohibit the taking of wild fry for aquaculture use. Some countries have laws concerning the import of exotic species, while others do not.
There is a general lack of the infrastructure needed to support aquaculture. Even in countries where there are trained personnel in sufficient numbers, research facilities are inadequate or lacking. Supplies of essential inputs are insufficient, especially in the smaller islands. Most feed ingredients may have to be imported, as would any specialized hatchery equipment.
There is no adequate mechanism for exchanging aquaculture information in the Caribbean, and there appears to be relatively little contact between countries concerning aquaculture. Frequently the people responsible in one country have only a vague idea, or do not know, of developments within the region that would be of benefit to them.
The conditions confronting a potential fish culturist in the Greater Antilles seem essentially quite similar to those prevailing in continental countries at this latitude. The islands appear to be relatively well suited for culture of freshwater fish and it might be expected that such culture activities can provide an increase in rural fish supplies and some addition to rural employment within a short period of time. For this to come about, Governments need to provide a reasonably efficient extension staff, which has access to facilities needed for production and transport of fingerlings. Some work may have to be done by Government fish culturists to adapt established culture techniques to local price structures and availability of feed and fertilizers.
The ongoing rural fish culture project in Jamaica, and the proposed project for a similar development in Haiti, can provide information which might be of use for development of pond culture in Cuba and the Dominican Republic.
Rice is a staple ingredient in the diets of the inhabitants of the Greater Antilles. In Haiti, but also in Cuba and the Dominican Republic, some of the rice grown is irrigated. Culture of fish (tilapia and/or carps) in irrigated rice fields would contribute to the supply of fish in rural areas. The Mission has proposed a pilot rice-cum-fish culture project for Jamaica. If implemented successfully, the project could become a training centre in rice field fish culture.
Several species of fresh water shrimps are indigenous to the Caribbean islands, among them Macrobrachium carcinus and M. acanthurus. The Mission is of the opinion that culture of fresh water shrimps can be developed in the Greater Antilles and the fact that M. rosenbergii grows large and fast is not a sufficient reason for considering it the most suitable species for culture. It is the consumer who eventually accepts or rejects the shrimp at the price offered in the market place. Well-established local taste preferences may mean that smaller shrimp, or slower growth rates, are compensated for by higher market prices.
Culture of M. rosenbergii is being carried out in large farms in Central America (Honduras and Costa Rica). It has been tried in Jamaica; a detailed feasibility study was carried out for Grenada. The pilot-scale project for culture of M. rosenbergii proposed by the Mission for Jamaica, could provide experience of value for development of this culture also in other parts of the Caribbean.
It would seem that the physical environment of the Greater Antilles (large perennial rivers, lagoons and protected bays) make these islands better suited for development of mariculture than the smaller volcanic islands. The latter are short of naturally occurring nutrients and of protected bays. Nevertheless, as the economic viability of most kinds of potential mariculture at present is not known, and as it would take some time to establish its viability, the Mission concludes that in the Greater Antilles, Governments' development objectives at this time will be reached more surely by development of fresh water aquaculture than by development of mariculture.
Aquaculture will not play an important role in the economies of the smaller islands in the immediate future. However, few serious attempts have been made to adapt existing aquaculture technology to the islands and one cannot now exclude that some forms of mariculture may become important. Apart from the tourist industry the Lesser Antilles have very few economic activities where they have a natural advantage to exploit and trade with other nations. Some forms of mariculture may, when developed, have such advantages. However, before considering mariculture in more detail a few observations need to be made on fresh water fish culture.
Some of the reasons why fresh water fish culture does not look like becoming a selfsustaining economic activity were identified in the sections on Antigua, Montserrat and St. Lucia. Unfavourable topography, little rainfall, and shortage of good agricultural land make it seem very unlikely that culture of fresh water fish will contribute significantly to the supply of fish in the islands, or to other development objectives. This does not exclude the possibility that cultures that make more intensive use of land and water (such as culture of tilapia or carp in association with pig or poultry farming) can become economically attractive.
As has been seen in the previous sections not all types of mariculture are a priori suitable for the smaller Caribbean islands in spite of the abundance of both water and sunshine. The absence of protection from wind and waves in combination with low nutrient content (relative to productive fishing grounds) limit the type of culture systems that can be used. They should either be such that the cultured species is relatively unaffected by storms or the installations be so cheap (relative to earnings) that they can be easily replaced or readily repaired. To be unaffected by storms, culture systems should either be so simple that no fixed installations are required or the culture be carried out in well constructed installations, situated so high or far away that storm damage is eliminated or minimized. In the latter systems it will be natural (given the often high capital costs) to aim at a high production per unit area, or volume of water, which means that feeding becomes essential.
In the rest of this section we will consider some of the species that might be grown in the culture systems outlined above. They are: cockle, queen conch, turtle, seaweed, marine fish, oysters and mussels, and marine shrimp.
Cockles occur in shallow bays. Culture technology is simple, cheap and in general well suited for use by poor, rural people. Small seed cockles are collected from natural beds and transported to growing beds where they are scattered as evenly as possible. Harvesting is done, over a period of two or three months, eight to nine months after sowing. In Malaysia yields from cockle culture are in the order of 35 to 40 t/ha (Pathansali, 1977).
Labour costs account for the major share of production costs. This makes the culture insensitive to inflation, and, as most of the labour is unskilled, the culture is socially highly relevant. Little is known about the local market for cockles and this would seem to be the major issue at present. Also, the extent of naturally occurring resources and their exploitation must be known before any rational plan of cockle culture can be developed.
Considerable interest has been generated in the stocking of queen conch (Strombus gigas) as a region-wide project. Conches feed on a variety of plants including manatee grass and turtle grass which grow well on sandy bottoms in relatively silt-free water. They are usually found at depths between 3.5 and 16 m. Most grounds are now over-fished and it has been proposed to construct a conch hatchery and re-stock areas depleted by overfishing. The following is an extract from a paper in which conch culture is proposed:
‘The general approach would be to: (1) collect queen conch egg cases and hatch the eggs under laboratory conditions; (2) rear larvae through metamorphosis; (3) culture the juveniles under controlled laboratory and semi-natural conditions and release them as juveniles into selected grass flat areas where they could grow naturally and later be harvested by local fishermen. Once the hatchery produces large numbers of small juveniles, the programme emphasis would shift to (4) evaluating the effectiveness of re-establishing depleted conch stocks in selected areas by mass seeding of laboratory reared juveniles’.
This seems a laudable project for several reasons; conch is an important component of artisanal fishing in many areas; it has an export market; it does not require special processing or handling; it can be stored alive for considerable periods in small enclosures while awaiting transport to the market or processing.
However, even with a re-stocking programme, improved management of the resource is essential. More attention is needed to define the requisite management procedures and how to get them implemented on a regional basis; simply ascertaining the technical and economic viability is not enough, as few, if any, of the countries at present possess the capability of enforcing legislation or restricting access to fishing grounds. Attempts to exert control at the market place could result in having conch shipped to a market in another country, if all countries do not have similar programmes. In these circumstances it is not clear who would be willing to bear the operating costs of the hatchery. None of the proposals seen by the Mission pay sufficient attention to these problems. Investigations and discussions on management of the resource should therefore go hand-in-hand with hatchery development and seeding operations.
Sea turtle populations in the Caribbean region have been declining for a long time. Five species are known to live there - Lepidochelys olivacea, the olive ridley; Dermochelys coriacea, the leatherback; Caretta caretta, the loggerhead; Eretmochelys imbricata, the hawksbill; and Chelonia mydas, the green turtle. The taking of turtles for their meat, shells and eggs has depleted stocks drastically. Two of these species are endangered.
Farming and ranching of sea turtles are controversial subjects. Turtle farming could be based on collection of eggs, or hatchlings, in the wild, but such a practice could reduce the recruitment to the already dwindling stocks of wild sea turtles. However, it is known that the loss to predators can be very high just after the eggs are hatched and during the first period at sea. Mariculturists therefore feel that the damage done through collection of eggs in the wild could be compensated by restocking.
The U.S. National Marine Fisheries Service is undertaking studies which will include: imprinting studies designed to repopulate nesting beaches; rearing of marine turtles for seeding; release and monitoring of hatchlings, juveniles and sub-adult turtles; and tags and tracking technology (Klima, 1978). Initiation of new turtle farms based on collection of eggs and young in the wild should be held in abeyance until this research generates sufficient data to justify it.
There is a turtle farm located in the Cayman Islands, where the green turtle is cultured in large ponds. The turtle has been reported to mature and reproduce at the farm.
Turtle farming of the kind carried out in the Caymans is not suitable for small-holder activities: considerable areas and capital are required to establish the farm. Feed, and other operating expenses, demand considerable funds as turtles reach commercial size (45 kg) after about 3–4 years. Turtles are caught throughout the Caribbean and there is a market for the meat. There is considerable uncertainty with regard to export markets for turtle products. The largest market in the area, that of the U.S.A. has been closed to turtle products in the hope of reducing the risk that turtle stocks will be depleted beyond the point of no return.
Several of the species occurring in the Caribbean islands can be cultured in floating net cages. Groupers would seem to be especially suited. This type of mariculture is being developed in Southeast Asia, in the Mediterranean, and in Northwest Europe. Temperatures in the Caribbean are ideal and the water is clean and not subject to severe quality fluctuations due to fresh water runoff.
However, before any commercialization could occur, considerable research would have to be conducted with indigeneous species in support of a programme of development of maturation and spawning under controlled conditions, of hatchery technology, and of growing the fish to marketable size. With a good programme of research it may be possible to commercialize cage culture of marine fish in three to five years.
The culture could be organized as a small-holder activity and investments in cages are normally relatively modest in comparison with the value of fish produced. In spite of these advantages it is not certain that cage culture will become widespread amongst the smaller Caribbean islands; most of the volcanic islands are short of protected sites and feed may become a costly item. These two issues should be investigated early.
Culture technology for seaweed is fairly well known for some species and it needs only to be adapted to local conditions. The technology is simple and well suited for coastal fishermen. It makes use of installations that can be easily replaced or repaired. The initial investment in materials and supplies is minimal. There is good potential for culture of Gracilaria debilis for local consumption and export. This is also true for a number of Caribbean islands other than St. Lucia, where culture trials are about to start. It is possible that culture of carageenan-producing seaweeds such as Euchema sp. and Hypnea sp. could also be undertaken. These seaweeds are often found in natural concentrations insufficient to sustain commercial harvesting, but stocks would be sufficient as a source of seeds for mariculture.
Seaweed culture can be organized as a small-holder activity; labour costs dominate production costs. Culture of seaweeds could thus contribute both to earnings of foreign exchange and to employment of unskilled manpower. Seaweed culture could in the Mission's view become one of the priority cultures for the Caribbean area.
Oyster and mussel culture can be organized as small-holder activities and do not require, normally, as high investments per unit area of production as do pond based cultures. Nevertheless, the smaller islands in the Caribbean do not appear to have sufficient sites with the requisite quantities of planktonic food in the water to make this a worthwhile objective for mariculture development. Also, it would appear that only small quantities are consumed in the islands.
Intensive mariculture facilities can be constructed so far from the sea that the risk of storm damage would be minimized or eliminated, and the high-priced coastal stretch left for other uses. In the past, most of the islands employed windmills in sugar cane processing and it is likely that with new windmill technology the trade winds with their more or less constant speeds of 24 to 32 km/h could be harnessed for pumping. The small tidal fluctuation reduces the effort needed for pumping.
Penaeid shrimp, marine reef food fish, such as snappers and groupers, and ornamental fish are suitable for culture in land-based intensive mariculture facilities. Environmental conditions, especially water temperatures, are ideal for shrimp culture.
The obvious type of system to investigate first would be intensive culture in concrete raceways, large tanks, or especially constructed small ponds with a more or less continuous flow of water and feed. This technology is most developed for penaeid shrimp. It would be desirable to use an exotic shrimp like Penaeus monodon or P. vannamei. Post larvae could be imported and then reared to adults to serve as brood stock. These would be spawned and reared in a hatchery. Every island would not need to have its own hatchery or brood stock. A central facility could ship eggs, or nauplii, by air to small hatcheries. Also, post-larvae could be shipped. Commercially prepared feeds, made especially for shrimp, are available and could be imported.
Yields in the order of 2 kg/m2 could be expected from raceways three times per year. Trials to determine local costs and yields at specific sites would have to be carried out.
Although the technologies necessary for intensive shrimp culture have been developed, they have not been strung together at any one place sufficiently well for intensive shrimp culture yet to have earned investors good returns. In addition, shrimp culture will contribute only marginally to employment and supply of fish to the islands. Even the net foreign exchange earnings that shrimp culture could earn in the Caribbean are much below gross receipts from the exports of the cultured shrimps, as know-how, equipment and possibly also part of the feed would have to be imported.