Environmental Engineering Reference
In-Depth Information
are promoting biodiversity conservation in the rural areas by supporting snail
farming within and outside conserved forests.
Sources of snails for rearing
In the dry season snails bury themselves into loose soil or decaying vegetation,
enclose their shell in a thin, white membrane, the epiphragm, and hibernate.
They normally emerge from hibernation during the rainy season between the
months of March and October when conditions are moist and conducive for their
growth. During this period snail producers collect their stock from the wild in
the undergrowth of plantains, banana, coffee, and cocoa farms and in forest
undergrowth. Some snail collectors report that debarked branches of
onwe
are
stuck in the ground to attract the snails, thereby facilitating their collection. In
the forest, snails are also found under
Ficus
species on whose fruits they feed.
Alternately, snail farmers purchase their stock from the market or from other
producers anytime during the year.
Housing
For housing the snails, two systems are used: an indoor system and pasture/
outdoor system. In the modern indoor system, snails are cultured in plastic con-
tainers, which are arranged on wooden shelves or galvanized iron pipes. They may
also be raised in wooden boxes. Container sizes are variable. A 60
30 cm
container can house about 100 snails weighing about 50 g each. The housing
units are provided with entrance for tending the snails, and small spaces are
allowed to let in dim, diffused light since the snails are sensitive to high light
intensity. All open spaces around the containers are covered with wire netting to
prevent the snails from escaping and to exclude predators. The bases of the con-
tainers are covered with moist sandy, loamy soil and some leaf litter to simulate
the natural habitat and to allow them to burrow and prepare their laying pit.
After laying, the eggs are collected and kept in breeding boxes under shade or in
a room and provided with a warm, humid environment to facilitate hatching. The
eggs hatch after 15-40 days and the newly hatched snails are collected and raised
in another box until they are big enough to be transferred into the fattening pens.
Farmers in the rural areas can easily adopt the indoor system since the rural
housewife is used to maintaining a few snails in containers close to the kitchen
for family use on a short-term basis. Such a project may be sited in the backyard
and the kitchen waste may be conveniently used as supplementary feed.
Containers that are easily available in the villages such as large clay pots and
strong woven baskets with appropriate lids may be used to house the snails.
The modern outdoor/paddock system for raising snails involves clearing
the site and marking out the area to be fenced. The snails are then confined in
