182
C. B. HICKLING
most of the fish are caught in the sluice gates, into which they are
attracted by an inflow of water. Cobb does not say how long the fish
remain in the ponds to grow to a commercial size.
D. Brackish-water ponds at Arcachon
There was also no management of the 300 hectares of brackishwater ponds at Arcachon. Even the shallow “ jas ” were not tilled,
or at least no mention of tilling is made by Am6 (1938) or le Dantec
(1955). The ponds were stocked haphazardly by enticing the young
mullet and eels into the sluices, by allowing a slow current to flow out
of them in the spring (as in the Russian limans), and there seems to
have been no control of the rate of stocking. Harvesting was done
by beating the fish into trammel nets or, if only a few fish were needed,
they could be lured into the sluices by allowing a slow current to flow
in from the sea. In the winter, the fish too small for market would
shelter in the deep peripheral ditches, though le Dantec says that there
could be severe mortality during very cold weather. Fontaine (1968)
speaks of this industry as in disuse, and hoped for its future revival
using a more complete system of fish culture, especially the artificial
breeding of grey mullet for the controlled stocking of the ponds.
E. North Italian lagoons
Even in the great 100000 hectare pond complexes in the north
Italian lagoons there seems to be no cultivation, or none is mentioned
by Beadle (1946), Vatova (1962), d’Ancona (1954), or de Angelis (1960).
The pond management consists chiefly in the maintenance of the sluice
gates and deep peripheral channels, which is done during winter.
Probably, the very large size of the ponds (300-500 hectares) makes
cultivation impracticable, even though, a t times of low water level,
there may be very large areas of the pond bottoms uncovered (Fig. 11).
I n the early spring the sluice gates, and also the smaller subsidiary
gates called ‘‘ cogolere ”, remain permanently open so as to attract the
maximum number of fry of grey mullet and elvers, though considerable
quantities of other useful fish, such as Sparus, Chrysophrys, atherines,
and bass, also enter. From about the second week in May, the sluice
gates are opened only on the high tides, so as to take in the maximum
amount of sea water. So long as the immigration of young fish into
the ponds continues, the smaller fish are guided t o sheltered separate
ponds called “ sergei ”. In these small and sheltered ponds, the young
fry brought from elsewhere to supplement the naturally immigrating
young fish are also placed. When these fish have become acclimatized
to the pond conditions, they can swim out into the main pond.
C. B. HICKLING
most of the fish are caught in the sluice gates, into which they are
attracted by an inflow of water. Cobb does not say how long the fish
remain in the ponds to grow to a commercial size.
D. Brackish-water ponds at Arcachon
There was also no management of the 300 hectares of brackishwater ponds at Arcachon. Even the shallow “ jas ” were not tilled,
or at least no mention of tilling is made by Am6 (1938) or le Dantec
(1955). The ponds were stocked haphazardly by enticing the young
mullet and eels into the sluices, by allowing a slow current to flow out
of them in the spring (as in the Russian limans), and there seems to
have been no control of the rate of stocking. Harvesting was done
by beating the fish into trammel nets or, if only a few fish were needed,
they could be lured into the sluices by allowing a slow current to flow
in from the sea. In the winter, the fish too small for market would
shelter in the deep peripheral ditches, though le Dantec says that there
could be severe mortality during very cold weather. Fontaine (1968)
speaks of this industry as in disuse, and hoped for its future revival
using a more complete system of fish culture, especially the artificial
breeding of grey mullet for the controlled stocking of the ponds.
E. North Italian lagoons
Even in the great 100000 hectare pond complexes in the north
Italian lagoons there seems to be no cultivation, or none is mentioned
by Beadle (1946), Vatova (1962), d’Ancona (1954), or de Angelis (1960).
The pond management consists chiefly in the maintenance of the sluice
gates and deep peripheral channels, which is done during winter.
Probably, the very large size of the ponds (300-500 hectares) makes
cultivation impracticable, even though, a t times of low water level,
there may be very large areas of the pond bottoms uncovered (Fig. 11).
I n the early spring the sluice gates, and also the smaller subsidiary
gates called ‘‘ cogolere ”, remain permanently open so as to attract the
maximum number of fry of grey mullet and elvers, though considerable
quantities of other useful fish, such as Sparus, Chrysophrys, atherines,
and bass, also enter. From about the second week in May, the sluice
gates are opened only on the high tides, so as to take in the maximum
amount of sea water. So long as the immigration of young fish into
the ponds continues, the smaller fish are guided t o sheltered separate
ponds called “ sergei ”. In these small and sheltered ponds, the young
fry brought from elsewhere to supplement the naturally immigrating
young fish are also placed. When these fish have become acclimatized
to the pond conditions, they can swim out into the main pond.