Several varieties of the migratory birds like Lesser whistling Teals and Open bill storks feed on different varieties of mollusks like snails, etc.
The local tribal population can be induced to undertake snail farming project under MGNREGA scheme of the Government, the apple snail variety may serve to supplement the normal diet of the villagers as well and is a rich source of protein.
Some such varieties of snails are of the subgenus Achatina , Archachatina and Pila.
Constructing a snailery for breeding Achatina (Bengali- "Samuk") and Archachatina variety of Land snail
Choosing a system: the options
The type and dimensions of a snailery depend, obviously, on the snail growing system chosen, and on the quantity of snails produced.
As far is housing is concerned, your snail farm could be extensive,
semi-intensive, or intensive, in increasing order of complexity, management and financial inputs. Three options might be considered:
1. Extensive system: outdoor, free-range snail pens.
2. Mixed, or semi-intensive system: egg laying and hatching occur in a controlled environment; the young snails are then removed after 6-8 weeks to outside pens for growing or fattening or both.
3. Intensive: closed systems, for example plastic tunnel houses, green-houses and buildings with controlled climate.
Regardless of the size and type of the snail farm, the housing system
must meet the following conditions. It must be:
1. escape-proof; snails are escape prone and unless prevented from doing so they will quickly wander all over your (or your neighbour's) garden or house.
2. spacious , in accordance with the growing stage of the snails (hatch-lings, juveniles, breeding snails, or mature snails fattened for consumption). Snails suffer from overcrowding, which impedes their development and increases the risk of diseases. Suitable rearing densities range from > 100/m for hatchlings to 7-10/m for breeding snails.
3. easily accessible and easy to work in or with , for handling the snails, placing feed, cleaning and other tasks.
4. well-protected from insects, predators and poachers.
Different materials can be used for building snaileries, depending on price and availability.
1. Decay- and termite-resistant timber. In South East Asia poles can be made of a species like teak.
2. Sandcrete blocks, or mudbricks.
3. Galvanized sheets, polythene sheets.
4. Chicken wire, for protection.
5. Mosquito nets or nylon mesh, for covering the pens as protection against insects.
6. Second-hand materials, like car tyres, oil drums and old water tanks.
What snails eat
Snails are vegetarian and will accept many types of food. All snails will avoid plants that have hairy leaves or produce toxic chemicals.
Market waste
Because snails are vegetarians, the cheapest way to feed them is by collecting rejected but recommended food from marketplaces. At the end of any market day, some perishable vegetables and fruits still useful for snail consumption can be collected from the dumping areas. A. achatina baby snails thrive best on leafy vegetables. At all other stages, a diet made up of the following ingredients is recommended:
1. Yam leaves contribute fairly high amounts of protein (2.9%), calcium (60 mg/kg) and phosphorus (52 mg/kg), and moderate amounts of thiamine (vitamin B 1) and riboflavin (vitamin B2).
2. Paw paw fruit provides moderate amounts of carbohydrates and high amounts of ascorbic acid (which is a feeding stimulant for many plant-eating animals, including snails).
3. If the soil is not high in calcium, supplementary calcium will be needed. This can be provided by sprinkling
snail shells onto leafy vegetables.
Other common and nutritious feeds, banana, cabbage, and even cassava leaves. Younger snails are fed tender leaves.
4. Snails need water! Most is supplied by the food they consume, but additional water must be supplied in the growing pens: a water-soaked sponge or a dot of cotton wool for hatchlings and juveniles, in shallow dishes (otherwise the snails may drown) for mature and breeding snails.
Constructing a snailery for breeding Pila globosa (Apple snail- Bengali- Guglee) variety of freshwater snail
Construct six small ponds- (i) two snail breeding ponds (15′× 4′× 4′ ) separated by 4 ′ of space in between the two for breeding ground, surrounded by 3 ′ wide egg laying ground;(ii) mature snail stocking pond (6′× 4′× 4′ ); (iii) juvenile hatching and collecting pond (6′× 4′× 4′ ) (iv) yearling nursery pond (6′× 4′× 4′ ).
Such small dimensions of the breeding pond are suggested for making the opportunity for spontaneous
movement and close contact of P. globosa to copulate easily. Water depth (3 ′ - 3.6 ') should be ensured above 3″ - 4 ″ of bottom soil.
Apple snail requires moist grassy soil for egg laying, so grass should be planted on the 3 ′ wide egg laying
ground surrounding the breeding ponds. Water line should be arranged so that depending on the need, the breeding pond could be filled and waste water drained out.
Juvenile hatching and collecting pond (6 ′× 4′× 4′) covered by fine wire or mosquito net having suitable mesh size for dropping down the juveniles after hatching out from the eggs. Arrangement for taking off the wire-net and transferring the juveniles from the pond to nursery pond and nursery pond to stocking and aestivating area should be ensured.
In all the cases aeration should be ascertained for maintenance of favourable temperature, Dissolved Oxygen.
Feeding apple snails
Natural food plants for apple snails are common water hyacinth, toka pana or water lettuce, among the others.
The water in which they live should be clean and clear and there should be rapid cleaning of dead snails and decayed food plants and frequent change of water.
Acknowledgement:
i) Sri Durgadas Goswami, IAS, DM, Dakshin Dinajpur
i) Sri Durgadas Goswami, IAS, DM, Dakshin Dinajpur
ii) Practical guide on snail farming by Cobbinah
iii)Research papers of researchers of the University of Rajsahi, Bangladesh, available over the internet.
