ESTUARINE FISH FARMING
121
tory species such as Scatophagus, Tarpon, Epinephelus sp., Teuthis sp.,
Mugil cephalus L. and Lixa macrolepis (Blkr) is allowed to enter the
enclosure on the rising tide, and is retained when the gates are shut.
The fish are kept for 6-8 months, feeding chiefly on the resources of
the pond, but are given some supplementary food if necessary. I n view
of the list given above, the harvest must consist mostly of predators.
These simple and inexpensive ponds are the predecessors to the large
areas of fully-embanked pond-systems of the Philippines, Java, Taiwan
and Italy, in which a true fish culture takes place.
Intermediate in position are the Russian and Rumanian limans in
the Black Sea. As Antipa (1937) has pointed out, the action of waves
and currents on the north-west coast of the Black Sea (following a
natural law by which seas try to rectify irregularities in their coastline)
has set up long sand-bars which close off bays and small estuaries
(limans). These are used for raising fish, the Russims referring to
them, in fact, as fish (mullet) farms. A channel connecting the enclosed
lagoon with the sea is maintained through this bar by dredging and
revetting. As the sea tries to restore the bar, as much as two thirds of
the cost of the fishery exploitation of these limans is spent on keeping
open the channel, which may be an artificial one (Ilin, 1954).
Young fish, chiefly golden grey mullet, Liza aurata (Risso), enter
the lagoon in spring, but when they try to return to the sea in autumn
they are caught in traps placed in the channel. The valli of the north
Adriatic are operated in the same way, and in both cases fish which,
at the end of the growing season are still too small to be marketed,
may be kept over winter in hibernacula to continue their growth in
spring.
Another industry which comes close to fish farming is the use of
traps in some of the Mediterranean lagoons. Belloc (1938) describes the
fishery at Biguglia in Corsica. This lagoon has an area of 1 500 hectares,
and has only one effective entrance, which is kept open by groynes and
by dredging. Near the entrance is a barrage made of stout posts driven
into the bed of the lagoon, which is very shallow, and this barrage has
gaps through which, in the spring, fish swim in from the open sea. At
the beginning of summer, these gaps are closed. The trapped fish
continue to grow fast in the very good feeding conditions.
During the summer, some fishing is done with various kinds of net,
but the chief fishery is in autumn, when the fish seek to return to the
sea. The gaps in the barrier are now furnished with elaborate traps in
which the fish are caught. The fish will represent a greater weight at
capture than on admission, but the growth will be at the expense of
the natural fertility of the lagoon, and fish culture is hardly involved,
121
tory species such as Scatophagus, Tarpon, Epinephelus sp., Teuthis sp.,
Mugil cephalus L. and Lixa macrolepis (Blkr) is allowed to enter the
enclosure on the rising tide, and is retained when the gates are shut.
The fish are kept for 6-8 months, feeding chiefly on the resources of
the pond, but are given some supplementary food if necessary. I n view
of the list given above, the harvest must consist mostly of predators.
These simple and inexpensive ponds are the predecessors to the large
areas of fully-embanked pond-systems of the Philippines, Java, Taiwan
and Italy, in which a true fish culture takes place.
Intermediate in position are the Russian and Rumanian limans in
the Black Sea. As Antipa (1937) has pointed out, the action of waves
and currents on the north-west coast of the Black Sea (following a
natural law by which seas try to rectify irregularities in their coastline)
has set up long sand-bars which close off bays and small estuaries
(limans). These are used for raising fish, the Russims referring to
them, in fact, as fish (mullet) farms. A channel connecting the enclosed
lagoon with the sea is maintained through this bar by dredging and
revetting. As the sea tries to restore the bar, as much as two thirds of
the cost of the fishery exploitation of these limans is spent on keeping
open the channel, which may be an artificial one (Ilin, 1954).
Young fish, chiefly golden grey mullet, Liza aurata (Risso), enter
the lagoon in spring, but when they try to return to the sea in autumn
they are caught in traps placed in the channel. The valli of the north
Adriatic are operated in the same way, and in both cases fish which,
at the end of the growing season are still too small to be marketed,
may be kept over winter in hibernacula to continue their growth in
spring.
Another industry which comes close to fish farming is the use of
traps in some of the Mediterranean lagoons. Belloc (1938) describes the
fishery at Biguglia in Corsica. This lagoon has an area of 1 500 hectares,
and has only one effective entrance, which is kept open by groynes and
by dredging. Near the entrance is a barrage made of stout posts driven
into the bed of the lagoon, which is very shallow, and this barrage has
gaps through which, in the spring, fish swim in from the open sea. At
the beginning of summer, these gaps are closed. The trapped fish
continue to grow fast in the very good feeding conditions.
During the summer, some fishing is done with various kinds of net,
but the chief fishery is in autumn, when the fish seek to return to the
sea. The gaps in the barrier are now furnished with elaborate traps in
which the fish are caught. The fish will represent a greater weight at
capture than on admission, but the growth will be at the expense of
the natural fertility of the lagoon, and fish culture is hardly involved,