A background information on swarming response of fish to artificial reef, reef-afinity, is presented to develop a reef technique as one of the methods for controlling fish bahavior. Nature and magnitude of the reef-afinity is variable according to fish species, its developmental stages and physiological conditions. In some fish species, the reef-afinity is emphasized along with growth of fish. Some fish are attracted not only reefs directly but also small living organisms gathering around reefs. For controlling fish behavior, the artificial reef techniques should be employed according to the specific function of reef, such as spawning area, shelter and resting place of fish.
