Reef Fishery
415
rapid regeneration of corals proceeds in places artificially "sowed" with
pieces of branches of ramose corals (Harriott 1983; Harriott and Fisk 1988).
Nevertheless, most researchers argue that the degradation of reef
ecosystems is practically irreversible, because, in practice, to put an end to
the human impact seems to be impossible (Weiss and Goddart 1977). In the
near future, the tendency most probably will be the reverse. Moreover, as it
was mentioned above, reefs might drown in future as a result of the
expected rise in sea-level because of the "green house effect" (Smith and
Buddemeyer 1986).
11.5 Reef Fishery
Among the resources of reefs most made use of by man are: (1) fish and
edible invertebrates: molluscs, holothurians, crabs, shrimps, crayfish,
polychaetes, urchins; (2) edible seaweeds; (3) shells and corals as souvenirs
and for collection; (4) lime and sand for construction; (5) raw materials for
production of drugs; and (6) recreational potential. Overexploitation of each
of these resources destabilizes the reef ecosystem, undermines its ability to
reproduce and thus leads to their loss. Therefore, the use of reef resources
needs a rational approach and scientifically based regimentation.
Fishery had been for long time one of the important sources of food for
people of tropical coasts (Marshall 1980). For aborigines of the islands,
fishery supplies the main portion of needed proteins. But since ancient times
reef fishery never has had a commercial purpose. All catch had been used
mainly by the fishermen themselves (Stevenson and Marshall 1974). It
corresponded not only to the old habits of the local people but also to the
poor applicability of industrial methods in fishery (heavy trawls, large gill
nets) in reef environments. Also, most reef fish are territorial and thus do
not form large aggregations, profitable for industrial fishery (Marshall 1980).
The total standing stock of reef fish is large, comprising about 9% of fish in
the world ocean (S.Y. Smith 1978). The biomass of fish on reefs is by 1-2
orders more than in pelagic intensively fished areas (cf. Table 6.7): 20200tha- 1 against 2-3t (Carpenter 1977; Russ 1984). Nevertheless, the
catch in reef zones does not largely exceed that in pelagic zones, comprising
5-50kgha- 1 against 25kgha- 1 in the fishery fields of the North Atlantic
(Table 11.5). But on small intensively and variously fished reefs the catch
could be kept up for a long time at a higher level - up to 100-200 kg ha- I
(Alcala 1979; Alcala and Luchavez 1981; Table 11.5). Such a high catch is
achieved there by taking mostly middle-sized herbivorous, omnivorous and
pelagic fishes, which represent the most numerous guilds. Among them
there are the acanthurids, scarids, siganids, basistids, and caesionids. The
curve of dependence of catch upon the intensity of fishing (number of
415
rapid regeneration of corals proceeds in places artificially "sowed" with
pieces of branches of ramose corals (Harriott 1983; Harriott and Fisk 1988).
Nevertheless, most researchers argue that the degradation of reef
ecosystems is practically irreversible, because, in practice, to put an end to
the human impact seems to be impossible (Weiss and Goddart 1977). In the
near future, the tendency most probably will be the reverse. Moreover, as it
was mentioned above, reefs might drown in future as a result of the
expected rise in sea-level because of the "green house effect" (Smith and
Buddemeyer 1986).
11.5 Reef Fishery
Among the resources of reefs most made use of by man are: (1) fish and
edible invertebrates: molluscs, holothurians, crabs, shrimps, crayfish,
polychaetes, urchins; (2) edible seaweeds; (3) shells and corals as souvenirs
and for collection; (4) lime and sand for construction; (5) raw materials for
production of drugs; and (6) recreational potential. Overexploitation of each
of these resources destabilizes the reef ecosystem, undermines its ability to
reproduce and thus leads to their loss. Therefore, the use of reef resources
needs a rational approach and scientifically based regimentation.
Fishery had been for long time one of the important sources of food for
people of tropical coasts (Marshall 1980). For aborigines of the islands,
fishery supplies the main portion of needed proteins. But since ancient times
reef fishery never has had a commercial purpose. All catch had been used
mainly by the fishermen themselves (Stevenson and Marshall 1974). It
corresponded not only to the old habits of the local people but also to the
poor applicability of industrial methods in fishery (heavy trawls, large gill
nets) in reef environments. Also, most reef fish are territorial and thus do
not form large aggregations, profitable for industrial fishery (Marshall 1980).
The total standing stock of reef fish is large, comprising about 9% of fish in
the world ocean (S.Y. Smith 1978). The biomass of fish on reefs is by 1-2
orders more than in pelagic intensively fished areas (cf. Table 6.7): 20200tha- 1 against 2-3t (Carpenter 1977; Russ 1984). Nevertheless, the
catch in reef zones does not largely exceed that in pelagic zones, comprising
5-50kgha- 1 against 25kgha- 1 in the fishery fields of the North Atlantic
(Table 11.5). But on small intensively and variously fished reefs the catch
could be kept up for a long time at a higher level - up to 100-200 kg ha- I
(Alcala 1979; Alcala and Luchavez 1981; Table 11.5). Such a high catch is
achieved there by taking mostly middle-sized herbivorous, omnivorous and
pelagic fishes, which represent the most numerous guilds. Among them
there are the acanthurids, scarids, siganids, basistids, and caesionids. The
curve of dependence of catch upon the intensity of fishing (number of