184
C. F. IIICKLINC
In autumn and until the end of December, as the temperature falls,
the fish in the valli endeavour to return to the sea ; at high tide the main
sluice gate is opened, and the fish press seawards against the inflowing
current. This migration is especially strong on stormy nights. The eels
tend to migrate most on moonless nights, but the grey mullet at full
moon (de Angelis, 1960). It will be noticed that the device of guiding
the fish into the traps by using a flow of water is world-wide.
The catching and sorting traps, which tend to become ever more
elaborate, are placed in the sluices. Metal grids of different mesh sizes
sort out the marketable fish, while the smaller fish are guided to groups
of small sheltered ponds called " conserve ". These are well protected
from the cold winds by trees. The smaller fish are overwintered here
(Fig. l l ) , (being fed in the meantime as required) to resume their
growth in the spring. Thus there is, in these valli, a succession of fish
crops in autumn and winter. A few fishing operations may also be
done in the ponds with nets in the summer.
F. Bheris of West Bengal
Descriptions of the bheris, or brackish-water fish farms of West
Bengal, have been given by Pillay (1954) and by Pakrasi et a2. (1964).
Pillay wrote rather pessimistically of their present position and future,
of the lack of incentive t o do culture operations, of silting up, and
neglect. Pakrasi et al. painted a better picture, though they listed
many serious problems, of which floods, drought, and silting were three,
together with a lack of exact information on the best means of operation, and adverse socio-economic factors. Saha et al. (1969) wrote as
though the best years of this industry were in the past. The decline,
they think, is due to over fishing in the rivers and creeks, leading to a
scarcity of fish fry for stocking, so that the operation of the ponds
scarcely pays. However, much is being done to improve the situation
by research into the occurrence of fry, and the supply of fry which enter
the ponds can be supplemented by seining the nearby areas of shallow
brackish water, where many fry are found.
From the end of February, brackish water is admitted to the
ponds on spring tides. During the full moon and new moon quarters,
the fry of the commercially valuable fish are generally plentiful, and
in order to obtain a good stock of these for the ponds, not only are the
main sluice gates opened, but additional gaps may be cut through the
embankments. To avoid excessive pressure on these embankments,
excess water may be let out at low tide. Provision is made t o prevent
the escape of the fish fry caught on the rising tide. When the pond
C. F. IIICKLINC
In autumn and until the end of December, as the temperature falls,
the fish in the valli endeavour to return to the sea ; at high tide the main
sluice gate is opened, and the fish press seawards against the inflowing
current. This migration is especially strong on stormy nights. The eels
tend to migrate most on moonless nights, but the grey mullet at full
moon (de Angelis, 1960). It will be noticed that the device of guiding
the fish into the traps by using a flow of water is world-wide.
The catching and sorting traps, which tend to become ever more
elaborate, are placed in the sluices. Metal grids of different mesh sizes
sort out the marketable fish, while the smaller fish are guided to groups
of small sheltered ponds called " conserve ". These are well protected
from the cold winds by trees. The smaller fish are overwintered here
(Fig. l l ) , (being fed in the meantime as required) to resume their
growth in the spring. Thus there is, in these valli, a succession of fish
crops in autumn and winter. A few fishing operations may also be
done in the ponds with nets in the summer.
F. Bheris of West Bengal
Descriptions of the bheris, or brackish-water fish farms of West
Bengal, have been given by Pillay (1954) and by Pakrasi et a2. (1964).
Pillay wrote rather pessimistically of their present position and future,
of the lack of incentive t o do culture operations, of silting up, and
neglect. Pakrasi et al. painted a better picture, though they listed
many serious problems, of which floods, drought, and silting were three,
together with a lack of exact information on the best means of operation, and adverse socio-economic factors. Saha et al. (1969) wrote as
though the best years of this industry were in the past. The decline,
they think, is due to over fishing in the rivers and creeks, leading to a
scarcity of fish fry for stocking, so that the operation of the ponds
scarcely pays. However, much is being done to improve the situation
by research into the occurrence of fry, and the supply of fry which enter
the ponds can be supplemented by seining the nearby areas of shallow
brackish water, where many fry are found.
From the end of February, brackish water is admitted to the
ponds on spring tides. During the full moon and new moon quarters,
the fry of the commercially valuable fish are generally plentiful, and
in order to obtain a good stock of these for the ponds, not only are the
main sluice gates opened, but additional gaps may be cut through the
embankments. To avoid excessive pressure on these embankments,
excess water may be let out at low tide. Provision is made t o prevent
the escape of the fish fry caught on the rising tide. When the pond