Aquaculture Certification - SEAFOOD Ecolabelling: Principles and Practice - page 129

damage but it turned out that using poorly drained, acidic mangrove soils to build
shrimp ponds resulted in poor productivity and many ponds were simply aban-
doned. Shrimp farmers have learned that the best sites for shrimp ponds are inland
from the intertidal mangrove fringe. As a result most of the larger intensive and
semi-intensive, so-called 'industrial' shrimp farms, do not displace mangroves. In
addition, legislation to protect mangroves is now enforced more effectively and the
rate of mangrove loss is slowing (Wilkie & Fortuna 2003). Aquaculture codes of
conduct produced by the FAO and GAA are unequivocal about the need to protect
mangroves. In 1997 GAA commissioned an international study by leading man-
grove experts. This culminated in six recommended management practices, which
form the first element of GAA's Codes of Practice for Responsible Shrimp Farm-
ing. Some poor communities in remote parts of countries such as Indonesia and
Vietnam still cut down mangroves to build shrimp ponds, so continued efforts at
education and enforcement are needed. The aquaculture industry needs assistance
from governments in tropical and sub-tropical developing countries to improve en-
forcement of mangrove conservation policies and to develop balanced strategies
for integrated use of coastal areas.
5.13.2 Fishmeal
Aquaculture, particularly of carnivorous species, is becoming the dominant con-
sumer of world supplies of fishmeal and fish oil, and this has prompted some
analysts (Naylor et al. 2000) to question its sustainability on the basis that supplies
of fishmeal and fish oil are limited by the productivity of industrial 'feed' fisheries.
This is an important issue to consider because these resources need to be managed
wisely, but there is no evidence to suggest that the aquaculture industry cannot
continue to expand by making use of the fishmeal that would otherwise go into
the feed of terrestrial animals and by steadily improving the efficiency with which
feeds are converted into flesh. Terrestrial animals can grow well with little or no
fishmeal in their diets, but many aquaculture species only do well on diets that con-
tain significant amounts of marine protein and lipids, which are most conveniently
supplied by fishmeal and oil. So it makes sense to divert fishmeal and fish oil to
aquaculture, the industry that values them most highly, leaving terrestrial animals
to rely more heavily on plant proteins.
Fishmeal and fish oil are mostly derived from species of pelagic fish that are
highly fecund, fast-growing and relatively low in food chains. They are typically
small, oily and boney and are not in high demand for direct human consumption,
despite their excellent nutritional characteristics. The annual output from feed fish-
eries has been stable for decades averaging 21.5 million tonnes, with some stocks
showing sensitivity to fluctuations in ocean currents and weather patterns, such as
El Ni no , rather than to fishing pressure (Huntington et al. 2004). Nonetheless, there
is clearly a need for stocks of feed fish to be carefully monitored and fishing activity
to be regulated to help keep stocks at healthy levels for sustainable fisheries and