Page 217 - (DK) Ocean - The Definitive Visual Guide

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HUMAN IMPACT
FLOATING COMMUNITY
Ocean sunfish often drift at the ocean’s LURING FISH
surface. They will investigate floating rafts
of seaweed and logs for potential food
such as small fish and crustaceans. Fish-attracting devices (FADs)
have increased catches in many
areas by making fish stocks easier
to exploit. However, they make
no contribution to biological
productivity because they simply
Drifting Homes gather fish together, and so may
contribute to overexploitation.
Many pelagic fish species are attracted to floating Artificial reefs also attract fish, but
objects that provide shelter from predators, currents, provide safe breeding sites, too.
and even sunlight. Floating logs and seaweed also
provide a meeting point. Fishermen have exploited
this tendency by using fish-attracting devices (FADs,
see panel, right) to concentrate fish in one area. These
vary from simple rafts with hanging coconut palm
leaves to complex technological devices.
Mini-ecosystems often develop on and around
large drifting logs. Seaweeds and goose barnacles
settle, providing shelter and food for crabs, worms,
and fish. Shipworms bore into the wood, and their
tunnels provide further refuge. Occasionally reptiles,
insects, and plant seeds
survive and drift on logs, SARGASSO HAVEN FISH-ATTRACTING DEVICE
and may eventually be Floating Sargassum seaweed Even simple FADs, such as this floating buoy OCEAN LIFE
provides a safe haven for the
washed ashore to colonize sargassumfish. More than in Hawaii, will attract fish. Juvenile jacks and
endemic Hawaiian damselfish can be seen
new places, including new 50 animal species have been sheltering under this one.
volcanic islands. recorded in this habitat.