ESTUARINE FISH FARMINU
189
find good feeding conditions, and so also do the very abundant prawns.
When the fields are drained to take the paddy harvest, the fishing
rights are leased out to skilled fishermen who use traps and cast nets.
These fisheries are very productive, cropping at the high rate of 3 600
lb/acre/annum (Pakrasi et al., 1964).
I n Kerala State in south western India, paddy fields border the
brackish-water lagoons, which form a system which extends for many
miles behind the coast. These fields grow a crop of paddy during
the rainy season, which ends in September, when inland drainage
water freshens the lagoons. This crop is harvested in October. Then,
with the dry season, the salinity of the lagoons increases, and preparations are made to take a crop of prawns by raising and strengthening
the low earth embankments which surround the paddy fields and
installing simple sluice gates in them (Menon, 1955). These sluice gates
are used, as has been described for Singapore, to carry in on a rush of
water as many prawn fry as possible. This process is repeated several
times to ensure the greatest possible number of fry in the fields. The
fry grow so fast in the fertile paddy-fields that fishing for those grown
to commercial size is soon begun, as in Singapore, by emptying the
fields through long nets set in the sluices. This fishery is repeated four
to five days after full and new moon throughout the winter, during
which the salinity of the lagoons can reach 33%,.
At the end of winter, the rains flush out the salt from the fields
and a new crop of paddy is sown. Thus these fields give two crops a
year, one of rice and one of prawns. About 11 000 acres give a prawn
crop which, after local requirements, still allows for the export of 3 800
tons of high-priced dry prawn meat. As with the bheris of West Bengal,
the owners of the paddy fields usually lease out the fields for the prawn
crop and they may thereby derive, as rent, an additional income of Rs
100-300 per acre.
I. Chanos culture in Java
I n Java the traditional method of raising Chanos is to take one
crop a year from the less brackish inland ponds and two crops a year
from the more marine and saline ponds. The success of the latter is
to have two overlapping groups of Chanos growing in the same pond.
In the inland ponds the calendar of operations is much as follows
(Schuster, 1952). I n October, about 1 000 Chanos fry per acre of pond
surface are placed in the fry ponds, and in November the grown
survivors are admitted to the rearing ponds. I n December, following
the clearance of vegetation, the growing fish are admitted to the
deeper parts of the ponds and by February to all sections of the ponds.
189
find good feeding conditions, and so also do the very abundant prawns.
When the fields are drained to take the paddy harvest, the fishing
rights are leased out to skilled fishermen who use traps and cast nets.
These fisheries are very productive, cropping at the high rate of 3 600
lb/acre/annum (Pakrasi et al., 1964).
I n Kerala State in south western India, paddy fields border the
brackish-water lagoons, which form a system which extends for many
miles behind the coast. These fields grow a crop of paddy during
the rainy season, which ends in September, when inland drainage
water freshens the lagoons. This crop is harvested in October. Then,
with the dry season, the salinity of the lagoons increases, and preparations are made to take a crop of prawns by raising and strengthening
the low earth embankments which surround the paddy fields and
installing simple sluice gates in them (Menon, 1955). These sluice gates
are used, as has been described for Singapore, to carry in on a rush of
water as many prawn fry as possible. This process is repeated several
times to ensure the greatest possible number of fry in the fields. The
fry grow so fast in the fertile paddy-fields that fishing for those grown
to commercial size is soon begun, as in Singapore, by emptying the
fields through long nets set in the sluices. This fishery is repeated four
to five days after full and new moon throughout the winter, during
which the salinity of the lagoons can reach 33%,.
At the end of winter, the rains flush out the salt from the fields
and a new crop of paddy is sown. Thus these fields give two crops a
year, one of rice and one of prawns. About 11 000 acres give a prawn
crop which, after local requirements, still allows for the export of 3 800
tons of high-priced dry prawn meat. As with the bheris of West Bengal,
the owners of the paddy fields usually lease out the fields for the prawn
crop and they may thereby derive, as rent, an additional income of Rs
100-300 per acre.
I. Chanos culture in Java
I n Java the traditional method of raising Chanos is to take one
crop a year from the less brackish inland ponds and two crops a year
from the more marine and saline ponds. The success of the latter is
to have two overlapping groups of Chanos growing in the same pond.
In the inland ponds the calendar of operations is much as follows
(Schuster, 1952). I n October, about 1 000 Chanos fry per acre of pond
surface are placed in the fry ponds, and in November the grown
survivors are admitted to the rearing ponds. I n December, following
the clearance of vegetation, the growing fish are admitted to the
deeper parts of the ponds and by February to all sections of the ponds.