118 Fish as feed inputs for aquaculture – Practices, sustainability and implications
fish to using formulated feeds, if the use of formulated feed is a more efficient form of
resource use. The general impression that such changes are difficult to bring about is
untrue, as exemplified by the recent adoption of best management practices (BMPs) by
small-scale shrimp farmers in India (Umesh, 2007).
As previously noted, feed development for a wide range of cultured aquatic species,
in particular the newly emerging marine finfishes, has lagged behind the progress that
has been made by the animal husbandry sector. With the increasingly negative public
perception of the use of fishmeal and fish oil by the aquaculture sector, as well as of
the use of trash fish/low-value fish for feeding cultured stocks, there needs to be a
concerted effort directed towards the development of diets with lower fishmeal/fish oil
content and to decrease the use of trash fish/low-value fish by small-scale farmers as
feed for cultured stocks. Perhaps this can be accomplished through a regional initiative
that brings together researchers, feed manufacturers, raw material suppliers and farming
communities. There also needs to be an emphasis on the improvement of farm-made
feeds, which are an important element in Asian aquaculture. Although this point has
been advocated previously (De Silva and Davy, 1992; New, Tacon and Csavas, 1995;
Tacon and De Silva, 1997), little headway has been achieved. Again, a regional approach
may be needed to determine ways and means of improving the efficacy of farm-made
feeds and the dissemination of appropriate strategies.
In China, the problems associated with the direct use of trash fish/low-value fish
as feed in aquaculture have recently drawn increased attention. During the National
Freshwater Aquaculture Development Planning Meeting in 2004, the concept of
"feed-fish culture", based on the success in mandarin fish culture in southern China,
was endorsed as a new thrust for developing high-value fish culture in the country.
The policy of the Chinese fisheries authority is to promote the development and
use of complete formulated feeds to gradually replace the direct use of trash fish/low-
value fish in marine finfish farming. Apart from the research and development in
feeds, feeding and culture technology, the central and local fisheries authorities are
now studying the feasibility of launching policies to provide suitable incentives to
encourage marine finfish farmers to shift to formulated artificial feeds.
Given the social, economic and technical factors associated with the use of trash
fish/low-value fish in China’s marine finfish culture, it is unrealistic to expect that trash
fish/low-value fish use will disappear in the near future. However, it is envisioned that
the use of trash fish/low-value fish for fish culture will come under stricter government
regulation and that the general trend in finfish culture will be towards an industry that
is more knowledge-based, healthier and more environmentally friendly.FIGURE 23
An aerial view of cage-culture practices in XinCun Bay, Hainan Island, China, where 570 families conduct
marine cage farming. Although each holding is small, the families collectively produce 100 000 tonnes
of high-value marine finfish, almost all of which are fed trash fish/low-value fish