Reef ecosystems extend throughout the tropics. Exploited by small-scale
fishers, reefs supply food for millions of people, but, worldwide, there
are growing worries about the productivity and current state of these
ecosystems. Reef fish stocks display many features of fisheries
elsewhere. However, habitat spatial complexity, biological diversity
within and among species, ecosystem intricacy and variable means of
exploitation make it hard to predict sustainable modes and levels of
fishing.