Fish as feed inputs for aquaculture: practices, sustainability and implications

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48 Fish as feed inputs for aquaculture – Practices, sustainability and implications


in aquaculture production will be needed. The main issue is whether the use of forage-
fish stocks and low-value bycatch (i.e. trash fish) for aquafeeds has environmental, food
security and poverty implications and what alternatives exist.

8.1.1 Regional patterns in aquafeed production and use
There is a marked difference among the global regions regarding the sourcing of
fish-based protein for aquafeeds. In the Americas and Europe, the intensive culture
of salmonids and growing use of carnivorous marine species result in the use of high-
performance formulated feeds using fishmeal from dedicated feed fisheries. In general,
the histadine-rich meals from South America are preferred, although Europe still
depends on regional stocks such as capelin and blue whiting. Given the rising cost of
fishmeal and fish oil and the competing demands from Asia, there has been a concerted
effort to develop plant-based protein supplements.
In Asia, while intensive shrimp aquaculture uses mainly compound feeds, the
majority of marine and finfish aquaculture still depends upon either trash fish or
simple farm-made feeds (themselves derived from trash fish). This represents a
simple, cheap and readily available source of protein, although conversion ratios and
environmental performance are poor. With a decline in many feed-fish stocks fished
by China and Japan, there is greater demand for global fishmeal supplies. Furthermore,
a combination of increased competition from other demands for key species, such
as anchovy for fish sauce production, and wider pressures to reduce environmental
impacts and increase productivity means that there is likely to be a partial switch from
trash fish to compounded feeds by small-scale producers. However, it is likely that
trash fish will continue to be an important feed component for some time to come (De
Silva and Turchini, 2009).
In Africa, most small pelagics from both marine and freshwaters are destined for
human consumption. In contrast to elsewhere, the majority of fishmeal produced in
the region is used for animal feeds rather than for aquaculture, which is still poorly
developed in most African countries (Hecht and Jones, 2009). Furthermore, with
the exception of Egypt and the Islamic Republic of Iran, most aquaculture cultivates
herbivorous/omnivorous species with low fishmeal requirements. Further expansion
of aquaculture in the region may see a greater demand for fishmeal produced by
small-scale fisheries, and increased demand by aquaculture may have consequences for
livestock-dependent communities should the supply become limited (see below).

8.1.2 Scope for greater use of feedfish
There is a general recognition that many of the feed-fish stocks could be better used
for direct human consumption. It is possible to can, marinate or otherwise process
key species such as Peruvian anchovy and Chilean jack mackerel. To date the resulting
products have been destined mostly for export, but there is considerable interest in
developing low-cost products for regional consumption, especially in the poorer areas
away from the coasts. One product – a risotto product from Peruvian anchovy – looks
particularly promising. In Europe, species such as capelin, Atlantic herring and even
blue whiting have potential for human consumption, although use of the main feed-
fish species for direct human consumption is driven by market and other economic
factors rather than by technical or product development constraints. As a result, there
is unlikely to be any dramatic change over the medium term in the production of feed-
fish species being used directly as food. However, this will depend upon a number of
extrinsic factors such as the availability and price of other feed protein commodities
such as soya meal.
In Asia, there has been much debate on the alternative uses of trash and low-value
fish (De Silva and Turchini, 2009). Trash fish is largely inedible and can only be used
for fish and animal feeds. However, there are opportunities for steering the use of
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