64 Fish as feed inputs for aquaculture – Practices, sustainability and implications
SUMMARY
Global and Asian aquaculture have witnessed a ten-fold increase in production from 1980
to 2004. However, the relative percent contribution to production of each of the major
commodities has remained almost unchanged. For example, the contribution of freshwater
finfish has declined from 71 to 66 percent in Asia but has remained unchanged globally over
the last 20 to 30 years. This fact has dictated trends in the use of fish as a feed for cultured
stocks. The growth in the sector has gone hand in hand with an increasing dependence
on fish as feed, either directly or indirectly. In a number of countries in the Asia-Pacific
region, the aquaculture sector has surpassed the capture fisheries sector in its respective
contributions to the gross domestic product (GDP). Aquaculture’s increased contribution
to national GDPs can be taken as a clear indication of the contribution of the sector to food
security and poverty alleviation.
The use of finfish and other aquatic organisms as a feed source can be through direct
utilization of whole or chopped raw fish in wet form, through fishmeal and fish oil in
formulated feeds, and/or as live fish, although the latter is uncommon and the overall
amounts used are relatively small. In the first two categories, the fish used are often termed
“trash fish/low-value fish”. Although attempts have been made to define this term, all
definitions have a certain degree of ambiguity and/or subjectivity.
In this regional review, the amount of fish used as feed sources based on the above
categories was estimated primarily from the production data, supported by assumptions
on the inclusion levels of fishmeal in formulated feeds and observed feed conversion
efficiencies for both formulated feeds and for stock fed trash fish/low-value fish directly. A
scenario for the use of fish as feed was developed by starting from the levels of aquaculture
production recorded in 2004 and assuming increases in production volumes of 10, 15 and 20
percent by 2010, respectively, for the three trajectories. In parallel, the pattern of wild fish
use as feed was projected to change as fish and shrimp farmers increasingly replace farm-
made feeds by incorporating trash fish/low-value fish with manufactured feeds that include
fishmeal. Also, the fishmeal inclusion rates in manufactured feeds are falling slowly, and
this has been incorporated into the projections.
The regional review also deals with the production of fishmeal using trash fish/low-
value fish in the Asia-Pacific region. Regional fishmeal production as a whole is relatively
low when compared with that of major fishmeal-producing countries such as Chile, Iceland
and Norway, amounting to approximately 1 million tonnes per year. However, there is
a trend towards increasing the use of fish industry waste, such as from the tuna canning
industry in Thailand. The fishmeal produced in the region is priced considerably lower than
globally traded fishmeal, but its quality is poorer. Total fishmeal use in Asian aquaculture
in 2004 was estimated as 2 388 million tonnes, the highest proportion of this being used
for crustacean aquaculture (1 418 million tonnes). Based on growth predictions (to year
2010) in the sector and improvements to feed quality and management, it is expected that
the quantity of fishmeal used in Asian aquaculture will be slightly less than at present. An
estimated 240 000 tonnes of fish oil is used in Asian aquaculture, principally in shrimp
feeds.
Based on production estimates of commodities in 2004 that rely on trash fish/low-value
fish as the main feed source, this regional review suggests that Asian aquaculture currently
uses between 2 465 and 3 882 million tonnes, an amount that is predicted to decrease to
between 1.890 and 2 795 million tonnes by 2010. The use of trash fish/low-value fish and
fishmeal by the aquaculture sector has been repeatedly adjudicated as a non-sustainable
practice, and globally the sector is seeking to reduce its dependence on fish as feed through
improved feed management practices and development of better quality feeds and feed
formulations using alternative ingredients. Over the next few years, decreases in the use of
trash fish/low-value fish are also expected to be achieved through better conversion of raw
materials into fishmeal and fish oil during the reduction processes.