<;P>;PROBLEM TO BE SOLVED: To solve problems that there are a plurality of points at issue from the viewpoint of expenditures and water quality maintenance and culture techniques on the basis of mass-production of crabs have not yet been established though various methods are devised for reducing cannibalism in culture of aquatic animals practicing violent cannibalism such as the crabs. <;P>;SOLUTION: A solution is accomplished by illuminating the water surface or an underwater part of a preserve in which seeds and seedlings of the crabs etc., are charged with lighting equipment, suppressing an active feeding activity of the crabs, and utilizing the organisms gathering therearound as baits. When the housing density of the seeds and seedlings is high etc., one or a plurality of shelters are installed at need. If other live baits or mixed baits etc., are used in combination to produce residual baits, the resultant residual baits mostly go out from the base of the preserve to the outside and deterioration of water quality in the preserve by putrefaction is thereby reduced. <;P>;COPYRIGHT: (C)2009,JPO&INPIT