ESTUARINE FISH FARMING
181
possible effect of withdrawing from the potential spawning stock those
fry reared in the limans. One would have thought that the fact that
the grey mullet fishery in the Black Sea still flourishes after 100 years
of doubt would have settled the matter.
Clearly, mullet rearing in the Russian limans depends on succesful stocking and, when fry are few, the considerable expense of
keeping the channels open and fitting up the fences and traps is not
worth while. Therefore, when the golden grey mullet are scarce in the
spring, Zambribortch (1962) suggested that more use might be made
of the other species of grey mullet, notably Mugil cephalus and M .
saliens. Though in the spring immigration of fry, the L. aurata are by
far the dominant (70-95%), M . saliens may occasionally comprise
25%. But in the later stages of the fry immigration (July to September)
the immigrants include a substantial proportion of both species, which,
because of their late arrival, cannot attain commercial size before the
winter. If overwintered, these late fry would grow to marketable fish
during the next summer. Because of this, wintering ponds warmed by
underground springs which have a year-round temperature of about
10°C, have been put up in the Shabolat liman, into which the fry are
guided from October to December. Here they are sheltered from the
fierce winter by screens and covers until, in March and April, they
return to the open liman to resume their growth. This closely resembles
the overwintering of small fish in the Italian valli. An effect of this
overwintering is that the harvest of fish from the Shabolat liman
may consist largely of M . saliens and M . cephalus. Of course, the
ideal remedy would be for the golden grey mullet to be bred artificially so as to make the liman operators independent of the natural
supply of fry, and there can be no doubt that this is being attempted.
C. Hawaiian jishponds
In the Hawaiian fishponds (according to Cobb, 1901) there is
practically no attempt at fish culture, a statement which was also
true of the barrachois of Mauritius which are so similar. In Hawaii,
Chanos and grey mullet are the chief fish raised. The young of these,
and other fish, may be induced to enter the ponds on the rising tide
through the opened gates. If not enough fish enter, the pond owner
or manager may hire fishermen, at the right season, to seine for young
Chanos and grey mullet and place them in the ponds to grow to a
marketable size. I n the pond itself there may be some fishing with
seines and gillnets, which is easy because of the shallowness of the
ponds which may be only 10 cm deep at low tides, and 100 cm at high
tides, the tidal rise and fall being small in these oceanic islands. But
A M I3 - 8
7
181
possible effect of withdrawing from the potential spawning stock those
fry reared in the limans. One would have thought that the fact that
the grey mullet fishery in the Black Sea still flourishes after 100 years
of doubt would have settled the matter.
Clearly, mullet rearing in the Russian limans depends on succesful stocking and, when fry are few, the considerable expense of
keeping the channels open and fitting up the fences and traps is not
worth while. Therefore, when the golden grey mullet are scarce in the
spring, Zambribortch (1962) suggested that more use might be made
of the other species of grey mullet, notably Mugil cephalus and M .
saliens. Though in the spring immigration of fry, the L. aurata are by
far the dominant (70-95%), M . saliens may occasionally comprise
25%. But in the later stages of the fry immigration (July to September)
the immigrants include a substantial proportion of both species, which,
because of their late arrival, cannot attain commercial size before the
winter. If overwintered, these late fry would grow to marketable fish
during the next summer. Because of this, wintering ponds warmed by
underground springs which have a year-round temperature of about
10°C, have been put up in the Shabolat liman, into which the fry are
guided from October to December. Here they are sheltered from the
fierce winter by screens and covers until, in March and April, they
return to the open liman to resume their growth. This closely resembles
the overwintering of small fish in the Italian valli. An effect of this
overwintering is that the harvest of fish from the Shabolat liman
may consist largely of M . saliens and M . cephalus. Of course, the
ideal remedy would be for the golden grey mullet to be bred artificially so as to make the liman operators independent of the natural
supply of fry, and there can be no doubt that this is being attempted.
C. Hawaiian jishponds
In the Hawaiian fishponds (according to Cobb, 1901) there is
practically no attempt at fish culture, a statement which was also
true of the barrachois of Mauritius which are so similar. In Hawaii,
Chanos and grey mullet are the chief fish raised. The young of these,
and other fish, may be induced to enter the ponds on the rising tide
through the opened gates. If not enough fish enter, the pond owner
or manager may hire fishermen, at the right season, to seine for young
Chanos and grey mullet and place them in the ponds to grow to a
marketable size. I n the pond itself there may be some fishing with
seines and gillnets, which is easy because of the shallowness of the
ponds which may be only 10 cm deep at low tides, and 100 cm at high
tides, the tidal rise and fall being small in these oceanic islands. But
A M I3 - 8
7