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The Stockholm Conference projected that annual harvests could approximately
double from 1970 levels to 'rather more than 100 million tonnes' (UN 1972b),
although the depletion of some fisheries by overexploitation was also
recognized. In the same year the world's largest fishery, the Peruvian
anchovy, crashed spectacularly, a result of years of unsustainable harvests
precipitated by a strong El Niņo event. Harvests from marine capture fisheries
did rise but failed to reach 100 million tonnes, fluctuating around 80-90
million tonnes from the mid- 1980s (see graph). Contrary to indications
that the global fisheries catch is stable, a recent study reveals that
catches have actually been declining for more than a decade (Watson and
Pauly 2001). The study shows that vast overreporting of catches by some
countries combined with the large and wildly fluctuating catch of the
Peruvian anchovy, have painted a false picture of the health of the oceans.
Aquaculture production, by contrast, has risen sharply but is entirely
dominated by Asia and the Pacific (see graph).
The Stockholm Conference recommended two basic approaches to fisheries
management: improving management information through research, assessment
and monitoring, and international cooperation. Despite great improvement
in the quality and scope of fisheries information, better fisheries management
has generally not been achieved. There has been an almost inexorable global
trend towards increasingly intense exploitation and depletion of fisheries
stocks (see figure), three-quarters of which are maximally exploited (FAO
2001), and many have collapsed. Global agreements aimed at sustainable
fisheries exploitation include the adoption in 1995 of an Agreement on
the Conservation and Management of Straddling and Highly Migratory Fish
Stocks, and the Code of Conduct for Responsible Fisheries developed by
the FAO.
Thirty years ago fisheries issues were considered almost
entirely in economic and political terms. Today fisheries activities are
increasingly recognized as environmental problems in the broader sense.
The global expansion in yields has been delivered by fishing on progressively
smaller species at lower levels in the marine food web (the knock-on effects
of which are not fully understood) as the top predators have been depleted
(Pauly and others 1998). The global by-catch of many million tonnes (Alverson
and others 1994) includes not only charismatic animals such as dolphins
and turtles but many other species. Effects on marine and coastal ecosystems
are poorly known but are probably substantial (Jennings and Kaiser 1998,
McManus, Reyes and Naņola 1997). Negative ecosystem impacts also result
from some types of fishing gear (such as that used for bottom trawling)
and destructive practices (such as blast fishing) which cause physical damage
to the habitat. Recognition of the complex inter-relationships between fisheries
and marine ecosystems, and the need for ecosystem considerations in the
management of capture fisheries, is reflected in the FAO Reykjavik Declaration
(2001) on Responsible Fisheries in the Marine Ecosystem.
While seafood is the primary source of protein for many coastal people,
especially the poor, the global demise of fisheries has not been driven
only by nutritional needs. Much of the catch is for luxury foods, or is
processed into livestock feed. The 'tragedy of the commons' - the absence
of a rational reason to restrain harvests that are freely available to
all - is one root cause of overfishing while at the other end of the spectrum
is so-called 'Malthusian overfishing' (Pauly 1990), when the desperately
poor have no choice but to glean the last of the resource. Many attempts
to manage fisheries sustainably have degenerated into a 'division of the
spoils' (Caldwell 1996). Political imperatives to maintain employment,
international competitiveness or sovereign rights of access have led to
fisheries subsidies estimated at up to US$20 billion annually (Milazzo
1998), although these are probably now declining.
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