Inland aquaculture

These guidelines provide advice on producing fish seed in small-scale hatcheries. This publication is also available in Oriya.

‘Spawn’ is the name for the young fish about three days old that are available from hatcheries. Sometimes these young fish are also called hatchlings. The spawn of catla, rohu and mrigal is about 6-8 mm long. At this stage, the ‘yolk sac’ is absorbed, the mouth opened and the fins fully developed. Spawn are reared intensively, first to the ‘fry’ size and then to the ‘fingerling’ size. All the three stages are marketed and collectively called ‘seed’.

The “fast fingerling system” can produce advanced fingerlings about two months earlier than they are normally available from fish farms.  The farmer uses just one pond for continuous growing until fingerling size is reached, and fewer fish are stocked. A farmer with a small, seasonal pond can produce fingerlings in one month. These can then be sold for a high price because everyone wants fingerlings as early as possible.

The fingerling rearing pond, like the nursery pond, should be free from weeds and predators. Submerged weeds and predators are killed by mahua oilcake, which then acts as a good fertiliser. If there are no weeds, to kill predators and competitors quickly you can just add 100 kg of urea followed 24 hours later by 200 kg of fresh bleaching powder for a 1-ha area of a 1-m deep pond.

In watersheds, medium irrigation projects can be useful for aquaculture even though these water bodies are many times larger than ponds, and are basically built for irrigation or water storage. However, the full potential of these water bodies is not yet realised. Net pens or cages can be used to rear fingerlings in such environments.

It is best to stock advanced fingerlings in large ponds, tanks, and in both small and large reservoirs, since they can better escape predators and competitors. Seasonal ponds, often 0.10-0.15 ha and 1.5-1.8 m deep can be used as rearing ponds for raising advanced fingerlings. Low water levels at the end of the season will make netting and harvesting easy.

Everyone wants advanced fingerlings as early after the rains as possible. They fetch a good price and make marketable fish production possible in seasonal ponds. One way to produce early season advanced fingerlings is to grow them in perennial ponds and store them at high density with minimal feeding for the coming year. Whe such "stunted" fingerlings are stocked into ponds with good feed they grow fast and can be marketed in about 6-8 months.

Common carp is a foreign fish and there are several varieties. The variety used in Western Orissa is the fully scaled carp, which suits the tropical climate. Common carp lives and feeds near the pond bottom and can be grown with the Indian major carps, catla, rohu and mrigal as a 'polyculture' (which means growing many different types of fish together). It can also be grown alone, as a 'monoculture' in rice fields with high dykes that retain water.

These guidelines provide advice on producing fish seed of the Indian major carps in hapas within ponds to improve survival.

In this issue:

Nursery rearing of silver barb Puntius goniotus. Artemia enrichment and biomasss production for larviculture. Seed production of mud crab Scylla serrata in India. Macrobrachium on the southwest coast of India. Fish wastes in urban and suburban markets of Kolkata: Problems and solutions. Groups of poor women farming carps in leased ponds, Bangladesh. Lymphocystis disease and diagnostic methods in China. Mesocosm technology advances grouper aquaculture in northern Australia.

It was common to believe that fish cannot be cultured in seasonal ponds. However, fish can be produced in any pond of any size, anywhere in Orissa, provided that the water quality is good enough. A small and shallow pond that retains water for two months can be used for raising fry. A larger and deeper pond holding water for three to four months can be used for fingerling production.

If the place where fish live is good and healthy, fish rarely die from diseases. If we stress fish by roughly handling them, by keeping too many together, or by not feeding them well, they may suffer from disease. Depending on the disease, we may see lots of fish die in a short time, small numbers of fish deaths every day, reduced growth, marks on the fish, or a change in the way they look or swim.

Fresh fish is so popular in much of eastern India that harvesting will usually draw a crowd of pond side customers. Marketing is no problem so long as the quantities are small. When bulk quantities are fished out a trader, wholesaler or a middleman may take the fish and depending on the distance, time of the day and season, transport them to the market with or without ice.

These guidelines illustrate good practice for broodstock handling and management using practices that are suitable for small-scale operations. This document is also available in Oriya.

Any pond can be used to grow fish, but a pond that is dug specially for fish culture usually has a regular shape, a flat bottom with a slight slope along its length. When deciding where to locate a new pond, you should consider the landscape, land use, soil texture (15% clay is best for pond construction and water holding), water supply (consider quality, quantity and seasonality), security (from theft) and convenience (maybe close to your house).

When selecting a good place for a pond, an engineer may seek advice from local people, a biologist or an economist. It may be difficult to find an ideal site but it is necessary to look at the available sites before the work on pond building begins – so that it holds water, does not collapse or cost too much and will not waste effort and money. There are lots of things to think about before finally recommending a site.

In this issue:

Small-scale pond culture in Bangladesh. Issues and challenges in community-based aquaculture. Aquaculture as an action programme building confidence and self-worth. Transforming policy recommendations into pro-poor service provision. Grow out of spotted Babylon to marketable size in polyculture with seabass. Influence of economic conditions and global shocks on grouper markets. Status of cobia hatchery technology in Vietnam. Organic shrimp raceway system. Macrobrachium rosenbergii in Vembanad Lake. Management of monogenean parasites.

This paper advocates strategies, processes and practices that enable: livelihoods approaches rather than resource-based approaches, ‘direct’ institutional and policy development, rather than ‘project demonstrations’, and support for regional, national and local communications. It was presented at the Symposium on Participatory approaches in reservoir fisheries management: Issues, challenges and policy, October 4-6th 2004 at the Culture Club Resort, Dambulla, Sri Lanka hosted by the National Aquaculture Development Authority in collaboration with FAO..

Wild-harvest fisheries for live reef fish are largely over-exploited or unsustainable. Sustainable aquaculture – such as that of groupers – is one option for meeting increasing demand for reef fish as well as potentially maintaining livelihoods of coastal communities. This report draws upon secondary literature, media sources and four diverse case studies from at-risk reef fisheries, to frame a strategy for encouraging sustainable aquaculture as an alternative to destructive fishing practices. It was commissioned by the APEC Secretariat.

Sulawesi has the largest coral reef area in Indonesia, at the epicenter of worldwide marine biodiversity, but is one of the areas most threatened in Southeast Asia by destructive fishing practices. This case study reviews the potential for aquaculture to provide alternative livelihoods for fishers within the context of an integrated, community-based coastal management plan with involvement of local communities empowered to control and steward their resources so that they can conserve and utilise them sustainably.