Overexploitation of the world’s fisheries is the
subject of much recent concern (FAO 2002, Pauly et al.
2002,Hilborn et al. 2003). Although the global production of
fish and fishery products continues to grow, the harvest from
capture fisheries has stagnated over the last decade.Today numerous
fish stocks and species have declined since their historical
peaks, and some have even collapsed, leading to urgent
calls for more stringent management and the establishment
of protected areas (Roberts et al. 2003). However, the discussion
of the current fisheries crisis has focused nearly exclusively
on marine resources, and to some extent on
associated threats to marine biodiversity, particularly those affecting
charismatic animals such as seabirds, marine turtles,
dolphins, and whales. The fisheries of inland waters have received
only slight consideration within global analyses (FAO
1999,Hilborn et al. 2003,Kura et al. 2004).Here we summarize
and evaluate the evidence that overfishing in inland waters is
occurring and is a contributing factor to the decline of freshwater
biodiversity.We define inland fisheries as the capture
of wild stocks of primarily freshwater fish, including migratory
species that move between fresh water and the oceans.
Although aquaculture significantly augments the supply of certain
species and contributes a substantial fraction to the overall
harvest, we focus on capture fisheries of natural stocks.
Fishing and the activities surrounding it—processing,
packing, transport, and retailing—are important at every
scale, from the village level to national and international
economies. Fishing is a crucial source of livelihoods in developing
nations, particularly for low-income families in
rural areas where job options are limited. Small-scale commercial
and subsistence fishing often provides the employment
of last resort when more lucrative labor opportunities cannot
be found (Kura et al. 2004). This is particularly true for
inland fisheries. Although there are no global estimates of the
number of people engaged in inland fisheries, in China alone,
more than 80% of the 12 million reported fishers are engaged
in inland capture fishing and aquaculture (Kura et al. 2004).
The contribution of fisheries to the global food supply is
also significant. In 2000, fish and fishery products constituted
15.3% of the total animal protein consumed by people
(FAO 2003). About 1 billion people—largely in developing
countries—rely on fish as their primary animal protein source
(calculation based on Laurenti 2002), and this is especially true
for poor rural communities. For example, within the lower
Mekong basin, the average consumption of fish and other
aquatic animals is estimated at 56 kilograms (kg) per capita
per year (Hortle and Bush 2003), and may reach 71 kg per
capita per year in high-yielding fishing areas such as the
floodplains around Tonle Sap Lake in Cambodia (Ahmed et
al. 1998). In comparison, the global average is 16 kg per
capita per year (FAO 2002).