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heavily harvested fish populations, except, perhaps herring and
similar fish that mature early in life. An investigation of over
90 different heavily harvested stocks have shown little, if any,
recovery 15 years after 45–99% reduction in biomass (Hutch-
ings, 2000). This is particularly true as most catch reductions
are introduced far too late (Shertzer
et al
., 2007). Indeed, ma-
1950
0
100
Stocks (%)
underdeveloped
developing
fully exploited
over exploited
crashed
80
60
40
20
1960
1970
1980
1990
2000
Figure 3. The state of the World’s fishery stocks.
rine extinctions may be significantly underrated (Casey and
Meyers, 1998; Edgar
et al
., 2005). More importantly in this
context is not the direct global extinction of species, but the
regional or local extinctions as abundance declines. Local and
regional extinctions are far more common than global extinc-
tions, particularly in a dynamic environment like the oceans.
0
0
100
Per cent of global catch
Depth
1950
2000
2004
80
60
40
20
2000
4000
6000
8000
10000
Figure 2. Estimated per cent of the global catch taken at depths
for the years 1950, 2000 and 2004,
which illustrates how fishers
are moving further offshore (and often deeper) to catch fish.