Question

Give the merits and demerits of fish culture?

Answer 1

Culture fishery is a kind of business and research activity concerned with the culturing, feeding, breeding and production of fishes in marine and freshwater ecosystems. The basic advantage (merit) of fish culture is that it decreases our dependence on natural sources of fish. We can obtain fish of desired species is desired numbers by aclturing them.
Some merits of culture fishery are :

1.  Fish as food: Various species of fish are cultivated extensively as food. Some of the species grown are rohu, mrigal, catla etc.
2.  Fish for controlling diseases: Various fish species are, reared to control diseases like malaria, yellow fever etc. The larvivorous fishes like Gambusia are reared which eat up the larvae of mosquitoes and prevent the spreading of disease.
3. Economic value: Besides fishes, various oysters are also reared in culture fishery. These oysters are cultivated for pearls they make, which are of high economic importance.
4. Source of income: The fishing industry has brought a lot of income to the farmers in particular and the country on the whole. Blue Revolution is also gaining popularity on the same lines as the “green revolution.
5. Fishes are also reared for other by-products like fish oil, manure, glue, leather etc. Thus, fish farming is advantageous, economical and profitable from a business point of view. There are however certain problems or demerits associated with fash farming/culture fishery. They are :
   • It poses a threat to biodiversity. Only economically important and valued fishes are grown ( fish monoculture) which leads to the extinction of rare and economically less important fishes.
   •  Sometimes, such exotic species are introduced which cause the extinction of local fish species.