Analysis of fisheries suggests marine ecosystems can recover

11/10/2009

                A recent study provides evidence that efforts to rebuild
depleted fish stocks are worthwhile, finding signs of recovery in five major
marine ecosystems. Diverse management tools can successfully balance
conservation with commercial fishing, allowing fish stocks to recover in
overexploited areas, say the authors.

                Overexploitation of fish stocks has serious consequences for
the sustainability of fisheries and for the healthy functioning of marine
ecosystems around the world. Yet efforts to restrict fishing are often
resisted by fishermen concerned by short-term social and economic impact,
especially those whose livelihoods depend on fishing.

                An international team of researchers evaluated the condition
of marine fisheries and the effects of fishing in 10 of the world's largest
marine communities. The study examined the range of fishing rates that could
provide high yields while maintaining most species from both a commercial
and conservation perspective. In addition, they investigated management
programmes which were successful in rebuilding marine ecosystems.

                The research demonstrated fishing levels had been
substantially reduced in five of the 10 ecosystems studied: Iceland,
Newfoundland-Labrador, the Northeast US Shelf, the Southeast Australian
Self, and the California Current ecosystem. Clear signs of rebuilding were
seen in several of these.

                The study examined less than a quarter of the global
ecosystems used for fisheries, all of which were intensively managed. Of
these areas, 63 per cent need to be rebuilt. 14 per cent of assessed stocks
had collapsed by 2007, although results varied regionally. For example, few
assessed fish stocks had collapsed in the eastern Bering Sea, whereas 60 per
cent had collapsed in eastern Canada.

                However, progress was highlighted in Kenya: successful
management strategies involving cooperation with local communities together
with restrictions on damaging fishing gear and the introduction of protected
areas has increased fish stocks, the size of fish caught and improved
incomes from fishing.

                A trade-off between allowable catches under fisheries and
conservation of vulnerable or collapsed fish stocks is possible under
well-designed management systems. Collapsed stocks can be rebuilt if
traditional methods such as catch quotas and community management are
combined with strategically placed fishing closures (depending on local
conditions), gear restrictions, widespread ocean zoning to separate areas
managed for fisheries and for species and habitat conservation.

                Rebuilding may take decades and will involve short-term
costs, especially reduced yields and the loss of jobs. A global view is
needed as those who depend on fisheries in poorer regions may have no
alternative food sources and incomes. In addition, developed countries
should not shift fishing pressures to less developed areas of the world:
strong governance is required to enforce compliance with rebuilding efforts.
Local differences between fisheries, ecosystems and governance need to be
considered when developing management strategies.

                Ideally countries should take action before overexploitation
becomes evident. The study found that only Alaska and New Zealand had the
foresight to act before that stage was reached.