Global trade in ornamental fish is worth approximately US$ 1.7 billion per annum. However, India's earnings from exporting ornamental fish are meagre, estimated at around US$0.2 million. Even Sri Lanka's exports are valuated at around US$ 8 million.
Almost 60 per cent of world trade is controlled by Singapore, Malaysia, Hong Kong, Taiwan and Japan. Israel and Japan are the leading exporters of goldfish and koi carp. Of these exports, 75 per cent go to Canada, Western Europe and the US, and demand is ever-increasing.
Developments in aquaculture technology have enabled ornamental fish exports to take a giant stride in recent years in most of the south-east Asian countries. The total authorised annual export of ornamental fish from Singapore alone stands at US$ 80 million, and Malaysia, Indonesia, Philippines, Maledives, Sri Lanka, Thailand, Taiwan and Hong Kong have also become important ornamental fish exporting countries in recent years.
The success of breeding aquarium fish depends on the species, as not all fish lay eggs. Some are viviparous "live bearers", such as mollies, platies, guppies and swordtails. Usually, for breeding purposes, four females and one male are let into a tank. A fertilised female can give birth to five broods without further mating. Each brood consists of 60 to 100 young, in the case of mollies and swordtails, and almost 200 in the case of guppies and platies.
Fish that lay eggs include goldfish, tiger barbs, golden rosy barbs, koi carp, gouramies and fighters. Usually, two males and one female are introduced to the breeding tank. After laying eggs, which hatch after 42-72 hours, the males and females are removed. In the case of fighters and gouramies, one male and one female are introduced in a glass tank.
An essential role of food in the breeding of various marine ornamental fish, is to obtain good coloration. Nutrients must be rich in natural marine pigments, the best sources of which are said to be frozen krill and copepods. In home aquaria with abundant algal growths, anemone fishes (clowns) obtain the necessary red and yellow pigments by grazing on small crustaceans on the walls and rocks.
A farmer could produce 5,000 juveniles by rearing 100 female and 25 male mollies in a total water spread area of 25m^2 having independent circular tanks of 0.5m. A net profit of US$ 1,000 could be generated in this way. As this improved orange molly is more attractive than the common orange mollies available in the market, it must have good market potential.
Induced breeding techniques have been developed in Indian major carps and Chinese carps by hypophysation and this has been successful for the commercial breeding of selected ornamental species. Large-scale rearing of ornamental fish has also been successful with the "dirt system", practiced in the USA and South East Asian countries. However, these aspects need careful examination before adoption in mass culture of ornamental fishes in India.
So far, the Indian government has recognized only reservoir fisheries, freshwater carp farming, prawn and shrimp farming and hatchery production of fish and shrimp seeds. Neither industrial status nor farming grade has been given to ornamental fish culture and the export of ornamental fish in the past has been neglected. At present, export of live tropical fish is meagre; the fish around the Andaman, Nicobar and Lakshadweep islands should be exploited as an alternative to fishing during the off-season. Also, mass production of ornamental fish via farming could be possible.
As ornamental fish are delicate, semi-intensive or intensive culture methods are the most suitable. At present, most ornamentals are grown indoors in cement, glass or earth tanks.
Aquarium keeping has become much more than just a hobby. Ornamental fish culture is flourishing. It is estimated that the world turnover in the aquarium fish trade already axceeds US$ 4,000 million, annually. Asian countries are the major contributors.
The cost of feed and water for ornamental fish is 20 per cent as against 70 per cent for feed fish; hence these can be easily cultured in places like Tamil Nadu and Rajasthan, where water availability is limited, as well as land-locked states like Madhya Pradesh, Bihar and Assam, and can be exported to coastal states. It is estimated that with the investment of 12,500 US dollars in a small space with limited water supply, an unemployed graduate in zoology may easily earn a monthly income of about US$ 1,000.
Beginners think in terms of a glass tank measuring 60 cm x 30 cm to hold 24 fish of 2.5 cm or 12 fish of 5 cm. Ornamental fish thrive in temperatures of 80-90F so some heating provision may be necessary. The breeding of marine ornamentals has not been seriously considered as yet. Only a few species have been raised commercially around the world. The anemone fish, Amphiprion spp., has been bred successfully in captivity, and the market for it has increased considerably. The latest technology of induced breeding by using pituitary extract, HCG, Ovaprin, decapeptide, and so on, may be taught to the needy people who are producing fishes for export.
(from article by A.S. Ninawe of CGO, New Delhi, India, in Fish Farmer International File, March/April 1997: 32-34)
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