Fisheries in the Pacific

The challenge of sustainability for Pacific Island village fisheries, a historical perspective
of Vanuatu’s marine resources carried out by the Australian Institute of Marine
Science in 1988, a total of 469 species of fish were visually identified (Williams
1990). Coral reefs form the ecosystem with the highest diversity of fauna but the
coral biotope is very restrictive for the populations living in it. The habitat favourable
to each species is quite small: one refers to microbiotopes, generally scattered from
each other. The ensemble of these microbiotopes form in the space a kind of threedimensional
mosaic where each element harbours a micropopulation composed of a
small number of fish of the same species. This low intraspecific diversity is accompanied
by strong specialisation, as much from the perspective of diet as habitat (Kulbicki
1992). Due to their small size, these micropopulations are sensitive to all intensive
exploitation on the part of fishers and their abundance per hectare is low. These two
factors, combined with the rich species diversity of the fish biomass, constitutes the
primary constraints on the fishing activity; added to them are seasonal variations in
fish abundance, which are particularly sharp in the case of small pelagic fish (Conand
1987). These constraints are prohibitive for fishers; they cannot circumvent them and
have no other choice than to integrate them into their capture strategies and
techniques. One is faced here with the invariants inherent in the structure of coral
habitats and in the ecology of fish that heavily impact the availability of fish on the
capture sites (fig. 3).
Figure 3: The availability of fish on subsistence fishing grounds,
a process associating invariance and temporality
The availability of fish on fishing grounds is also sensitive to two parameters
which evolve over time. These are the health of marine ecosystems and the density
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