206
C. F. HICKLING
to start aqua-cultural projects may be thwarted by local statutes and
by public resentment.
In the developed countries, therefore, it seems most likely that
future fish culture will be of the intensive kind as in Japan. The
success of Shelbourne (1964) in breeding plaice, soles and other
valuable flatfish in captivity opens the way t o broiler-house techniques
of fish raising. Kennedy (1969) is making similar trials with the culture
of the sablefish in Canada. The trials of commercial salmon and
sea-trout raising by Unilever have been mentioned. But, so far as is
known, none of these projects has as yet got off the ground. Cheap
fodder, mechanized handling, and first-class transport facilities are
all needed.
The increase in the numbers and power of thermal and nuclear
power stations, many of which are placed on estuaries, has made available large quantities of flowing water heated to many degrees above
that of the environment. The possibility of using this heat has attracted
much interest, and one of the possibilities canvassed is that of growing
fish intensively in the warmed water (see, for example, Nash, 1968 ;
Cole, 1968). The growth of fish is accelerated (within limits) by
higher temperatures, and may be continued during at least some of
the winter months when the ambient water becomes too cold for rapid
growth, or indeed for any growth a t all. I n cultures in which fish have
to be overwintered, the use of warmed water would allow of survival
and even of some useful growth.
It seems likely that the use of this heat on the full scale is more of
an engineering than a farming problem. The engineer wants to get the
heated water away as quickly as possible since the efficiency of his
condensers, and therefore of his turbines, depends on this. But the
farmer wants the heat t o be available in an accessible form, which
means either a slow passage or an efficient heat-exchanger. Agreement
will have to be sought between engineers and farmers on such matters
as ducting off at least some of the warmed water from the discharge
pipes, and the future design of power stations may incorporate systems
of cooling water disposal which make the warmed water available
without increasing the cost of power generation. For example, it
might be possible to discharge the heated water into a reservoir from
which it would flow away down a number of channels, each of which
could include many fish-rearing units.
I n a marine setting, the Japanese are understood to have had the
encouraging results that would be expected, in accelerating the growth
of fish (yellowtail) in water warmed by waste power-station heat. The
Russians have also been experimenting for some years with the warmed
C. F. HICKLING
to start aqua-cultural projects may be thwarted by local statutes and
by public resentment.
In the developed countries, therefore, it seems most likely that
future fish culture will be of the intensive kind as in Japan. The
success of Shelbourne (1964) in breeding plaice, soles and other
valuable flatfish in captivity opens the way t o broiler-house techniques
of fish raising. Kennedy (1969) is making similar trials with the culture
of the sablefish in Canada. The trials of commercial salmon and
sea-trout raising by Unilever have been mentioned. But, so far as is
known, none of these projects has as yet got off the ground. Cheap
fodder, mechanized handling, and first-class transport facilities are
all needed.
The increase in the numbers and power of thermal and nuclear
power stations, many of which are placed on estuaries, has made available large quantities of flowing water heated to many degrees above
that of the environment. The possibility of using this heat has attracted
much interest, and one of the possibilities canvassed is that of growing
fish intensively in the warmed water (see, for example, Nash, 1968 ;
Cole, 1968). The growth of fish is accelerated (within limits) by
higher temperatures, and may be continued during at least some of
the winter months when the ambient water becomes too cold for rapid
growth, or indeed for any growth a t all. I n cultures in which fish have
to be overwintered, the use of warmed water would allow of survival
and even of some useful growth.
It seems likely that the use of this heat on the full scale is more of
an engineering than a farming problem. The engineer wants to get the
heated water away as quickly as possible since the efficiency of his
condensers, and therefore of his turbines, depends on this. But the
farmer wants the heat t o be available in an accessible form, which
means either a slow passage or an efficient heat-exchanger. Agreement
will have to be sought between engineers and farmers on such matters
as ducting off at least some of the warmed water from the discharge
pipes, and the future design of power stations may incorporate systems
of cooling water disposal which make the warmed water available
without increasing the cost of power generation. For example, it
might be possible to discharge the heated water into a reservoir from
which it would flow away down a number of channels, each of which
could include many fish-rearing units.
I n a marine setting, the Japanese are understood to have had the
encouraging results that would be expected, in accelerating the growth
of fish (yellowtail) in water warmed by waste power-station heat. The
Russians have also been experimenting for some years with the warmed