ESTUARINE FISH FARMIXG
191
east monsoon crop, which is stocked a t a rate equal to 250-300 fry
per acre of pond surface.
I n June, July, and August, the east monsoon crop is admitted to
the rearing ponds and is then mixed with the remainder of the west
monsoon crop, which continues to be culled out and sold. A few specimens of the west monsoon crop are retained to be grown to very large
fish of 2-8 lb weight, for which there is a limited demand.
I n September, the Chanos calendar ends with preparations for the
reception of the new west monsoon fry, and general maintenance work.
I n most of the months of this calendar there is an important sale of
prawns, which are usually caught in traps placed along and at right
angles to the pond banks. At night the well-grown prawns emerge
from their hiding places in the mud and swim about the ponds parallel
with the banks. Thus they are caught in the traps, which are made
even more effective by lamps placed at their entrances. Unlike the
" sugpo " prawn of the Philippines, there is no culture of the prawns
in the Javanese ponds. The young larval and post-larval stages of these
penaeid prawns are carried into the ponds with the filling water, and
the only cultural measure is to try to take in as many prawn fry as
possible, using the methods already described in the case of the Singapore prawn ponds.
As prawns sell well and are cropped continuously, the pond operator
has a steady income to bridge intervals in the sale of Chanos and, in
consequence, says Schuster, they are usually wealthy people. Their
resilience was well shown during the depression years of the 1930s,
when they were able to find the capital to improve and extend their
ponds using the cheap labour then available.
As in the Singapore prawn ponds, the best catches take place at
night when the prawns are active, for during the day they burrow
in the mud, Schuster says that millions of young prawns must enter
a pond to give a normal yield of marketable prawns, so that overstocking with fry is hardly possible. The mortality of the young prawns
must be exceedingly high.
The above is the usual procedure where the pond operator handles
Chanos from the fry to the market, but a more efficient trend is apparent
in both Java and the Philippines, namely, the rearing of fingerlings for
sale to the farmers by specialist fry dealers. I n the usual way, a farmer
can only expect a 30% rate of survival of the planted fry, but these
specialists may achieve 70%. The progressive fish farmers buy these
fingerlings, which are past the dangers of infancy, and rear a succession
of them for market, with only a lO-12% loss. Three or four successive
crops can be raised in a year, so that a well-managed pond can be
191
east monsoon crop, which is stocked a t a rate equal to 250-300 fry
per acre of pond surface.
I n June, July, and August, the east monsoon crop is admitted to
the rearing ponds and is then mixed with the remainder of the west
monsoon crop, which continues to be culled out and sold. A few specimens of the west monsoon crop are retained to be grown to very large
fish of 2-8 lb weight, for which there is a limited demand.
I n September, the Chanos calendar ends with preparations for the
reception of the new west monsoon fry, and general maintenance work.
I n most of the months of this calendar there is an important sale of
prawns, which are usually caught in traps placed along and at right
angles to the pond banks. At night the well-grown prawns emerge
from their hiding places in the mud and swim about the ponds parallel
with the banks. Thus they are caught in the traps, which are made
even more effective by lamps placed at their entrances. Unlike the
" sugpo " prawn of the Philippines, there is no culture of the prawns
in the Javanese ponds. The young larval and post-larval stages of these
penaeid prawns are carried into the ponds with the filling water, and
the only cultural measure is to try to take in as many prawn fry as
possible, using the methods already described in the case of the Singapore prawn ponds.
As prawns sell well and are cropped continuously, the pond operator
has a steady income to bridge intervals in the sale of Chanos and, in
consequence, says Schuster, they are usually wealthy people. Their
resilience was well shown during the depression years of the 1930s,
when they were able to find the capital to improve and extend their
ponds using the cheap labour then available.
As in the Singapore prawn ponds, the best catches take place at
night when the prawns are active, for during the day they burrow
in the mud, Schuster says that millions of young prawns must enter
a pond to give a normal yield of marketable prawns, so that overstocking with fry is hardly possible. The mortality of the young prawns
must be exceedingly high.
The above is the usual procedure where the pond operator handles
Chanos from the fry to the market, but a more efficient trend is apparent
in both Java and the Philippines, namely, the rearing of fingerlings for
sale to the farmers by specialist fry dealers. I n the usual way, a farmer
can only expect a 30% rate of survival of the planted fry, but these
specialists may achieve 70%. The progressive fish farmers buy these
fingerlings, which are past the dangers of infancy, and rear a succession
of them for market, with only a lO-12% loss. Three or four successive
crops can be raised in a year, so that a well-managed pond can be